6 Discussions due in 36 hours

combs

06CH_Mossler_Development.pdf

Home >Education homework help >6 Discussions due in 36 hours

181

6Health and Wellness

iStock/Thinkstock

Learning Objectives

After completing this chapter, you should be able to:

• Analyze personal and circumstantial variables related to nutrition and activity that impact health and illness.

• Compare and contrast the most prevalent eating disorders.

• Outline common diseases of childhood and their potential consequences.

• Identify global health concerns and efforts that prevent childhood mortality.

• Examine common illnesses and diseases of adulthood.

• Evaluate research in the field of psychoneuroimmunology and analyze factors that have a psychological effect on health.

mos82599_06_c06_181-218.indd 181 2/11/16 8:26 AM

182

Prologue

Chapter Outline

Prologue

6.1 Nutrition and Activity: Lifestyles and Circumstances Nutrition and Weight Overweight and Obesity Malnutrition Activity

6.2 Eating Disorders Anorexia Nervosa Bulimia Nervosa Binge Eating Disorder

6.3 Illness in Childhood Asthma Diabetes

6.4 Maximizing Childhood Health Outcomes Childhood Mortality and Prevention Efforts Immunizations

6.5 Illness and Disease in Adulthood Sexually Transmitted Infections and Diseases Smoking and Use of Other Tobacco Cancer Diseases of the Cardiovascular System Chronic Obstructive Pulmonary Disease Degenerative Diseases of the Brain

6.6 Stress

Summary & Resources

Prologue Jeanne Louise Calment, who died in 1997 at age 122 1/2, is the oldest person on record. So as far as we know, then, the human lifespan is somewhere beyond 120 years. What is less clear are the factors that contributed to Calment’s extraordinary longevity. Did she have a special genetic makeup? A special way of living? Whereas the upper limit of the lifespan is exclusive to primary aging, life expectancy, or how long a person is expected to live, is associated with secondary aging. Scientists estimate the life expectancy at birth, which yields a different age than a cohort of adults who are just turning 65. That is, if you have already lived to 65, on average, you will live longer than a cohort that is starting at age zero. The estimated life expec- tancy of a country is the average age at birth that a resident in the country can expect to live (see Figure 6.1). It includes infants who die at childbirth, teens who die in accidents, adults who die from various causes, and the very elderly who live over 100 years. We can compare the life expectancy of one population with another population in order to discover factors that contribute to both longevity and mortality.

mos82599_06_c06_181-218.indd 182 2/11/16 8:26 AM

183

Country

Y e a rs

U. S.

In do

ne sia

Ch in a

Br az

M on

ac o

Au st ria

Fi nl an

d Ha

Af gh

an ist

M ex

ico

Ru ss

Ja pa

Ca na

Si er

ra L

eo ne

79.7

57.8

84.7 81.8 81.4

80.8

63.5

50.9

75.6

70.5

73.5

89.5

75.4

72.5

Prologue

What types of variables impact life expectancy? In low-income countries, lack of medical care affects overall life expectancy, as does AIDS, famine, poor sanitation practices, and childhood diseases. However, new research methods have allowed us to document more unusual trends as well. In Syria, war is the leading cause of premature death; India and China account for half the world’s suicides, which are also disproportionately high in Eastern Europe; in Latin America and the Caribbean, interpersonal violence is a top-5 cause of death in more than half the countries in the region. In contrast, it is a leading cause of death in only one other coun- try in the world, South Africa (Global Burden of Disease [GBD] 2013 Mortality and Causes of Death Collaborators, 2015).

Researchers study the different factors that contribute to variability in life expectancy within high-income countries as well. In the United States, life expectancy varies by region. The southern states dominate the shortest-living states, whereas the longest-living states are less concentrated in one area. There are additional differences according to ethnicity and occu- pation as well (Lewis & Burd-Sharps, 2015). Inevitably, differences exist due to secondary aging factors. Among all people, but especially for adults, there is unequivocal evidence that being a nonsmoker, maintaining a healthy weight, eating five or more servings of fruits and vegetables a day, and engaging in regular physical activity contributes to longevity. However, few people engage in all of these lifestyle choices (Moore & Thompson, 2015). So while there is much that we already know, dissecting the many correlates of life longevity and mortality is no easy task.

Figure 6.1: Life expectancy by country

Life expectancy varies greatly among regions of the world.

Source: Central Intelligence Agency. (n.d.). Country comparison: Life expectancy at birth. The World Factbook. Retrieved from https://www.cia.gov/library/publications/the-world-factbook/rankorder/2102rank.html

Country

Y e a rs

U. S.

In do

ne sia

Ch in a

Br az

M on

ac o

Au st ria

Fi nl an

d Ha

Af gh

an ist

M ex

ico

Ru ss

Ja pa

Ca na

Si er

ra L

eo ne

79.7

57.8

84.7 81.8 81.4

80.8

63.5

50.9

75.6

70.5

73.5

89.5

75.4

72.5

mos82599_06_c06_181-218.indd 183 2/11/16 8:26 AM

https://www.cia.gov/library/publications/the-world-factbook/rankorder/2102rank.html

184

Section 6.1 Nutrition and Activity: Lifestyles and Circumstances

6.1 Nutrition and Activity: Lifestyles and Circumstances In wealthy countries, nutrition and exercise are leading factors that contribute to quality of life and longevity. Diminishing numbers of people get enough exercise to burn off the increas- ing portions of food that we consume. In the United States, for instance, about two thirds of adults and one third of children are overweight, which leads to a host of possible health complications. But there are also significant numbers of adolescents and some adults that engage in dieting practices to lose weight even though they are of normal weight. Worldwide, on the other hand, 11.3% of the population is undernourished, including 13.5% of people in developing countries (e.g., Bhurtun & Jeewon, 2013; Fayet, Petocz, & Samman, 2012; Gusella, Goodwin, & van Roosmalen, 2008). These outcomes related to nutrition and activity result from a blend of individual, family, community, social, and political variables—main features of the ecological perspective. This section will explore these issues within the context of the developing person throughout the lifespan.

Nutrition and Weight In Chapter 4, we considered the role of nutrition in early infant care and some of the issues parents assess when feeding an infant formula or breast milk. As most children begin to exclusively eat solid foods in their second year, many parents in the United States go to great lengths to ensure that their children are eating enough. If provided with good choices, tod- dlers and preschoolers are actually quite good at controlling their nutritional intake. Many adults worry about how much children are eating, but they should focus instead on what they are eating. Anxious parents may stuff their children full of pizza, hamburgers, fried chicken nuggets, and macaroni and cheese several times a week—or even daily—because of worry about their children “starving.” However, if offered a number of nutritious choices at meal- time, children will learn to self-regulate. Alternatively, when the culture encourages young children to eat more than they naturally want to consume, overeating behaviors are rewarded and it can set a precedent for a lifelong weight problem.

It may seem self-evident, but research confirms that children generally follow the nutritional habits of their parents. It is the reason that comparatively more Japanese children eat fish and American children eat hamburgers. In an extensive survey of adolescent dietary habits, it was found that teenagers who ate more fruits and vegetables had parents who also ate more fruits and vegetables. Parents who drank more soda predicted teenagers who drank more soda and ate more fast food, and so on. Parents can have either a positive or a negative effect on their children’s eating behavior (Diamant, Babey, Jones, & Brown, 2009). Moreover, signifi- cant numbers of parents do not realize when their children become overweight, which can undermine the promotion of healthy nutritional habits (Lundahl, Kidwell, & Nelson, 2014).

Nutrition during adolescence sometimes becomes complicated. Teenagers must balance the nutritional requirements of a period of rapid growth with the temptations and availability of high-fat, low-nutrient foods. In early adulthood, the efficiency with which we burn energy is slowed, and we burn fewer calories. Due to career or educational pursuits, we often become less active during early adulthood, which compounds natural muscle loss that begins to appear around 30. Therefore, if adults continue to eat at the same rate as they did when they were younger—even if they engage in similar physical activities—they are likely to gain weight.

mos82599_06_c06_181-218.indd 184 2/11/16 8:26 AM

185

Section 6.1 Nutrition and Activity: Lifestyles and Circumstances

As we move into middle and late adulthood, physical changes result from both primary aging and secondary lifestyle choices. Men tend to put on weight around the midsection, whereas women tend to accumulate fat in the hips. On average, weight does not decline until people reach their mid-70s. Men and women who gain “apple shaped” belly fat are more at risk for health problems than people who gain “pear shaped” weight around their hips (Schenck- Gustafsson, 2009). Waist to hip ratio, one of the biomarkers for longevity, can tell you if you have an excess of belly fat. To calculate a healthy hip to waist ratio, divide the measurement of your waist by the measurement of your hips. Men should strive for a proportion of 0.90 or lower to minimize health risks based solely on waist to hip ratio; for women, 0.80 or lower is optimal. There are, however, moderate variations according to race, ethnicity, age, and body type (e.g., Price, Uauy, Breeze, Bulpitt, & Fletcher, 2006; WHO, 2011).

Good nutrition plays a major role in maintaining optimal health. For example, healthy eating can reduce the risk for many chronic diseases. Dietary guidelines for Americans (USDA, 2010) include bal- ancing the number of calories consumed with the number of calories “burned off.” Consuming more calories than the body needs leads to excess weight. Beyond this basic premise, there are many ways to compose a healthy diet. Most beneficial diets rec- ommend increasing nutrient-dense foods like veg- etables, fruits, whole grains, beans, seafood, poultry, eggs, and low-fat or non-fat milk products. Numer- ous studies recommend following what is known as the “Mediterranean diet” to reduce risk factors for chronic diseases. This diet emphasizes fruits and vegetables, nuts, whole grains, olive oil, fish, and, for some people, moderate consumption of wine (Ham- mar & Östgren, 2013). While consuming healthier food is beneficial, so is limiting foods that are high in salt, contain saturated or trans fats, cholesterol, and added sugars (USDA, 2010). Advances in food labeling have made it possible to be a smart shop- per and make more nutritious choices.

Overweight and Obesity In addition to calculating the waist to hip ratio, for consistency in research and for medi- cal purposes, we use body mass index (BMI) to standardize the terms overweight (BMI of 25–29.9) and obesity (BMI of 30 or more). Because of a continuing trend towards a heavier population, researchers have also begun to use the terms grade 2 obesity for a BMI of at least 35 and grade 3 obesity for a BMI of 40 or more. About half of overweight people in the United States at any particular age also reach the threshold for obesity; rates are generally higher than average among minority women and children from lower-income families (Ogden, Car- roll, Kit, & Flegal, 2014). Although overall trends are quite concerning, the obesity rate among children 2 to 5 years has been one particular bright spot. Since peaking at 14% in 2003, less than 10 years later it has dropped to near 8%. Figure 6.2 illustrates the childhood and adult- hood obesity rates since 2003.

iStock/Thinkstock

The “Mediterranean diet” encourages consuming vegetables, fruits, whole grains, nuts, olive oil, fish, and the moderate consumption of wine.

mos82599_06_c06_181-218.indd 185 2/11/16 8:26 AM

186

2003–2004 2005–2006 2007–2008 2009–2010 2011–2012 0

P e rc

e n

Calendar Years

2003–2004 2005–2006 2007–2008 2009–2010 2011–2012

P e rc

e n

Calendar Years

a) Prevalence of childhood obesity

b) Prevalence of adult obesity

Age range

All (ages 2–19)

Ages 2–5

Ages 6–11

Ages 12–19

Age range

All (ages ≥20)

Ages 20–39

Ages 40–59

Ages ≥60

Section 6.1 Nutrition and Activity: Lifestyles and Circumstances

Figure 6.2: Rates of obesity in the United States

The prevalence of childhood obesity has decreased since 2003, but the prevalence of adult obesity has increased. Approximately 39.5% of adults aged 40 to 59 are obese.

Source: Adapted from Ogden, C. L., Carroll, M. D., Kit, B. K., and Flegal, K. M. (2014, February 26). Prevalence of childhood and adult obesity in the United States, 2011–2012. Journal of the American Medical Association. Retrieved from http://jama.jamanetwork .com/article.aspx?articleid=1832542

2003–2004 2005–2006 2007–2008 2009–2010 2011–2012 0

P e rc

e n

Calendar Years

2003–2004 2005–2006 2007–2008 2009–2010 2011–2012

P e rc

e n

Calendar Years

a) Prevalence of childhood obesity

b) Prevalence of adult obesity

Age range

All (ages 2–19)

Ages 2–5

Ages 6–11

Ages 12–19

Age range

All (ages ≥20)

Ages 20–39

Ages 40–59

Ages ≥60

mos82599_06_c06_181-218.indd 186 2/11/16 8:26 AM

http://jama.jamanetwork.com/article.aspx?articleid=1832542

187

Section 6.1 Nutrition and Activity: Lifestyles and Circumstances

Worldwide obesity rates have followed the trend of the United States. The World Health Organization estimates that 39% of all adults are overweight and that 13% are obese (WHO, 2015c), which is more than double the rates of 30 years ago. Poor adult nutrition in low- income countries contributes to inadequate prenatal, infant, and childhood nutrition, includ- ing increased exposure to nutrient-poor foods that are high in fats and sugar. These patterns have contributed to sharp increases in childhood obesity while the concurrent problem of undernutrition in many of the same countries remains unresolved.

There is strong evidence that the road toward becoming overweight often starts with hab- its set during childhood. Multiple longitudinal studies have found about three quarters of overweight children are obese as adults (e.g., Guo, Wei, Chumlea, & Roche, 2002; Riedel et al., 2014; Thompson & Bentley, 2013). As a consequence, obesity at every age is correlated with multiple health problems later, including a host of cardiovascular diseases and pulmo- nary, endocrine, and even orthopedic problems, as extra weight puts added strain on bones and systems related to movement (Inge et al., 2013; Reilly & Kelly, 2011). It is conservatively estimated that obesity results in an additional $19,000 in lifetime medical costs (Finkelstein, Graham, & Malhotra, 2014).

Behaviorally, being overweight is associated with delayed motor development beginning in infancy and has a negative effect on coordination in middle childhood (Joshi et al., 2015; Slining, Adair, Goldman, Borja, & Bentley, 2010). This finding is not surprising because extra weight limits mobility for anybody. Remember also that motor development, discussed in Chapter 5, is intimately connected to brain development during infancy, exacerbating long- term consequences of being overweight.

Causes and Prevention Biology and genetics influence body type and how people react to certain foods (e.g., craving a particular kind of taste). But with few exceptions, obesity occurs because of an imbalance between caloric intake and energy usage. In rare cases, a genetic component is identified. Prader-Willi syndrome, for instance, is a specific genetic disorder. It is characterized by feed- ing difficulties during infancy that soon change to a preoccupation with food and overeating. This syndrome is rare, occurring in only 1 out of every 25,000 births (Chen, Visootsak, Dills, & Braham, 2007). On the other hand, the rise in obesity from less than 11% of adults in 1960 to 35% today cannot be attributed to genetics because human genetics do not change in such a relatively short period.

Experts say the trend toward more weight is because we eat too much fast food, have “super- sized” portions at home and in restaurants, do not exercise enough, pick meals that offer few nutrients, sit too much, and pick easier physical options (e.g., taking an elevator or driving instead of taking the stairs and walking). Young adults generally eat more than their grand- parents did and get less physical exercise (CDC, 2015a). The obesity problem in lower income areas is often attributed to the relatively inexpensive nature of fast food. However, there are reasons to question this conclusion. First of all, freshly prepared food is far less expensive than fast food. Secondly, the vast majority of obese adults are in the middle and upper income brackets (Ogden, Lamb, Carroll, & Flegal, 2010).

mos82599_06_c06_181-218.indd 187 2/11/16 8:26 AM

188

Section 6.1 Nutrition and Activity: Lifestyles and Circumstances

A larger issue occurs when there is decreased availability of fresh food. Poorer urban areas are often called food deserts because they lack traditional supermarkets where fresh food is available year round. In this way, SES predicts food choices, but does not cause poor food choices. Overall, there is an inverse relationship between income level and obesity in women that does not exist in men. In fact, among low-income black and Hispanic men, the relation- ship is reversed. That is, while obesity prevalence is greater among low-income minority women, it is also higher among high-income minority men. Rates of overweight and obesity have increased at all levels of income and education, suggesting a global trend rather than one exclusive to sex or SES.

So it appears that lifestyles at every income and educational level have changed in ways that promote obesity. It has become the norm to purchase less nutritional food in lieu of some- thing fresh and home-cooked. Snacks are often thought of as high-fat, low-nutrition products that come in a bag at the corner store, rather than easily prepared carrots, celery, and fruit. Once taste buds get accustomed to certain foods, neural processing in the brain may actually change so that the brain and body craves those foods (Page et al., 2011). In this way, the enjoy- ment of food becomes part of a natural conditioning process.

Malnutrition Though rates of overweight and obesity continue to rise in some areas of the world, getting sufficient nutrition is a daily struggle in others. One out of eight people in the world, or nearly 800 million, suffer from chronic under-nourishment (FAO, IFAD, & WFP, 2015). When nutri- tion intake is deficient either because of not enough food or not enough specific nutrients, it is called malnutrition. Without proper nutrients beginning in childhood, malnutrition leads to negative physical, cognitive, and social consequences (Anjos et al., 2013). About 3 million of the deaths among children younger than 5 years of age are associated with preventable malnutrition, representing 45% of all deaths in that age range. As Figure 6.3 shows, an addi- tional 159 million children suffer from stunting, a slow cumulative marker for malnutrition that is associated with poor motor skills and arrested mental development (Black et al., 2013; McDonald et al., 2013). Children who survive nutritional diseases suffer lasting damage to the body and brain (Müller & Krawinkel, 2005). The effects of malnutrition on brain development are cumulative, affecting later attention and learning ability, overall intelligence, and motor coordination.

Activity As mentioned in the nearby paragraphs, some speculate that the relatively low cost of fast food may influence rates of obesity. Consider this argument in more depth by calculating the weekly cost of dinner for four at two different fast food restaurants (four dinners at one loca- tion and three at the other). Then, calculate the cost of home-cooked meals for the same seven days. For recipe ideas, download Leanne Brown’s Good and Cheap cookbook for free (http:// www.leannebrown.com/). Compare cumulative time involved (including transportation) and the costs and benefits of the consumed nutrition.

mos82599_06_c06_181-218.indd 188 2/11/16 8:26 AM

http://www.leannebrown.com/

189

250 50

200

150

100

1990 1995 2000 2005 2010 2014

255

224 198

182 169

159

a) Stunting

N u m

b e r

o f ch

ild re

n a

ffe ct

e d

(m ill

io n s)

P re

va le

n ce

( %

)

250 50

200

150

100

1990 1995 2000 2005 2010 2014

161 142

126 114 104

b) Underweight

N u m

b e r

o f ch

ild re

n a

ffe ct

e d

(m ill

io n s)

P re

va le

n ce

( %

)

Number of affected (millions of children ages < 5)

Prevalence (% of children aged < 5)

Section 6.1 Nutrition and Activity: Lifestyles and Circumstances

Figure 6.3: Global child malnutrition trends, 1990–2014

Approximately 800 million people in the world suffer from chronic under-nourishment, leading to 159 million children who suffer from stunting, and 3 million childhood under-5 deaths. Though still high, since the adoption of the Millennium Development Goals, these kinds of consequences have declined considerably. Though percentages vary by region, interventions that have specifically targeted areas where malnutrition is widespread have reduced the overall proportion of underweight children from 28% to 17%.

Source: UNICEF. (2015, September 22). Child nutrition interactive dashboard: 2015 edition. Retrieved from http://www.data .unicef.org/resources/child-nutrition-interactive-dashboard-2015-edition.html

250 50

200

150

100

1990 1995 2000 2005 2010 2014

255

224 198

182 169

159

a) Stunting

N u m

b e r

o f ch

ild re

n a

ffe ct

e d

(m ill

io n s)

P re

va le

n ce

( %

)

250 50

200

150

100

1990 1995 2000 2005 2010 2014

161 142

126 114 104

b) Underweight

N u m

b e r

o f ch

ild re

n a

ffe ct

e d

(m ill

io n s)

P re

va le

n ce

( %

)

Number of affected (millions of children ages < 5)

Prevalence (% of children aged < 5)

mos82599_06_c06_181-218.indd 189 2/11/16 8:26 AM

http://www.data.unicef.org/resources/child-nutrition-interactive-dashboard-2015-edition.html

190

Section 6.1 Nutrition and Activity: Lifestyles and Circumstances

Maternal malnutrition during pregnancy causes another 800,000 neonatal deaths due to insufficient fetal growth (Black et al., 2013; Katz et al., 2013). Dramatic evidence of the effects of malnutrition is provided by studies of mothers during times of war that were also marked by famine. For instance, during the World War II Siege of Leningrad beginning in 1941, Ger- man troops cut off the food supply to the city for nearly 2 1/2 years. During and after this period, fewer children were born, and those who were had a higher incidence of prematurity and low birth weight (Antonov, 1947). Similar results were found in 1944–1945 Holland, when the country was subjected to a blockade by the Germans. Like the consequences in Len- ingrad, there were increased numbers of miscarriages, stillbirths (babies born dead), and birth abnormalities (Stein, Susser, Saenger, & Marolla, 1975).

The good news is that since the World Health Organization adopted the Millennium Devel- opment Goals (see section 6.4 for more information about these goals), these kinds of con-

sequences have declined considerably. Interventions that have specifically targeted areas where malnutri- tion is widespread have reduced the proportion of underweight children from 28% to 17%. Still, in many African and southern Asian countries, the proportion is considerably higher (Patwari, 2013; United Nations, 2015). Though poverty certainly contributes to under- nourishment in the United States, there is not the wide- spread serious malnutrition that is evident in war-torn countries like Afghanistan and severely impoverished areas in places as diverse as India and Fiji.

Marasmus and Kwashiorkor When children suffer from chronic malnutrition two specific life-threatening nutritional dis- eases result (see Figure 6.3). Marasmus occurs when children’s bodies waste away because they have not consumed enough calories. It is most common during the first year when there is insufficient breast milk (usually due to malnutrition in the mother), or formula and food are unavailable. Children become extremely thin and fragile, and their weak bodies are at higher risk for disease.

Kwashiorkor is a condition caused by not consuming enough protein, even in children who sometimes maintain a minimal calorie intake. When children eat only starchy foods that lack protein, the body begins to break down its own reserves. A distended stomach is the hallmark of kwashiorkor and is often seen in photos of starving African children. It also causes severe swelling in the feet, loss of teeth and hair, immunity problems, and a multitude of other com- plications. Kwashiorkor most often occurs after the age of one, when children are weaned from the breast and alternative protein sources are not available. Therefore, in areas where malnutrition is common, the World Health Organization and similar offshoots recommend that mothers of infants at risk for malnutrition continue breastfeeding until their children are at least 2 years old (WHO, 2014).

Critical Thinking

Consider the different types of variables that contribute to worldwide health. What are some of the specific individual, family, community, societal, or political variables that affect nutrition?

mos82599_06_c06_181-218.indd 190 2/11/16 8:26 AM

191

Section 6.1 Nutrition and Activity: Lifestyles and Circumstances

Activity So there is clear evidence that malnutrition leads to deficits in physical, cognitive, social, and emotional functioning, and there are also problems associated with eating too much food, especially when there is too little activity. According to both evolutionary insight and contem- porary research, the importance of daily physical activity cannot be underemphasized. Yet, like nutrition, there has been a recent cultural shift in habits. The World Health Organization (2010) and the CDC (2008) continue to reaffirm that school-age children should accumu- late at least 60 minutes of physical activity each day. Yet despite public campaigns to sup- port physical fitness (e.g., Michele Obama’s “Let’s Move” and the National Institute of Health’s Go4Life), part of the continuing trend in weight gain is due to our more sedentary lifestyle. Meanwhile, hours of physical education in school and among adults have been decreasing in the United States and elsewhere (e.g., Swaminathan, Selvam, Thomas, Kurpad, & Vaz, 2011). By the time children reach high school, fewer than 3 in 10 meet current recommendations (CDC, 2015c).

In young adulthood, fitness level is a good predictor of cardiovascular disease in middle age (Roger et al., 2011). Those who have a poor to moderate fitness level are also at greater risk for reduced brain volume and cognitive functioning, which may be due to less oxygen in the blood (Fuss et al., 2014). Engaging in healthy behaviors like regular exercise in midlife pro- motes health in later life such as better cognitive functioning and a lower risk of dementia. Those who engage in risky behaviors or have excessive stress in midlife are likely to have more difficulty in old age (Lachman, Teshale, & Agrigoroaei, 2015) According to the CDC, adults should include at least 150 minutes of moderate intensity (e.g., brisk walking) or 75 minutes of vigorous aerobic exercise spread out over each week, and participate in two days per week of strength conditioning; only 1 in 5 adults in the United States reaches this target (CDC, 2015c; USDHHS, 2009).

In addition, research continues to suggest that humans may not have been designed for sit- ting for long periods. Yet work has shifted from manual labor to sitting at desks. Sedentary behavior is a major risk factor for obesity, cardiovascular disease, diabetes, and cancer (Huys- mans, van der Ploeg, Proper, Speklé, & van der Beek, 2015). There is evidence that simply getting up and moving rather than remaining sedentary for long periods can prevent future problems, such as back pain. One large-scale study of over 220,000 adults found that sitting for long periods had a significant effect on death by any cause, regardless of the amount of other physical activity (van der Ploeg, Chey, Korda, Banks, & Bauman, 2012). It is increasingly found that leisure time activity is a preventive factor in certain forms of cancer as well (Farris, McFadden, Friedenreich, & Brenner, 2015; Patel et al., 2015). Movement, at every age, is essential to optimal health.

Section Review How have patterns of nutrition and exercise changed in recent years? What are the potential health effects of these changes?

mos82599_06_c06_181-218.indd 191 2/11/16 8:26 AM

192

Section 6.2 Eating Disorders

6.2 Eating Disorders Activity and weight have a strong association with self-image. This is especially true dur- ing adolescence. Teenagers ordinarily need to increase their caloric intake to keep up with accelerated growth, so body image issues complicate the potential problems of overweight and obesity. For some, increased focus on food and body can lead to psychological eating disorders. Surveys show that eating disorders affect 4% of adolescents, though only 0.2% suf- fers impairment that causes extreme personal distress. Though eating disorders occur during adulthood as well, the majority begin during adolescence. Most studies report a mean age of onset in the mid to late teens, but trends show that it has been falling (e.g., Favaro, Caregaro, Tenconi, Bosello, & Santonastaso, 2009; Holm-Denoma, Hankin, & Young, 2014; Smink, van Hoeken, & Hoek, 2012).

Anorexia Nervosa Anorexia nervosa is a severe body-image disorder in which individuals refuse to eat because of an obsession to maintain an unrealistically thin body. Individuals have a distorted view of what is considered normal and may not recognize their own distress (Merikangas et al., 2010). It has been reported that there may be as many as nine times more girls than boys who are affected, but recent studies show the gap closing (Smink et al., 2012; Swanson, Crow, Le Grange, Swendsen, & Merikangas, 2011). Anorexia often begins during early adolescence and can be difficult to treat. It has been reported that up to 10% of anorexics die within 10 years and as many as 20% die within 20 years, usually from heart or other complications related to tissue starvation. Though anorexia has the highest mortality rate of any mental disorder, a major national survey found the average duration among those who recovered was only 1.7 years, so recovery is not necessarily out of reach (Attia, 2010; Hudson, Hiripi, Pope, & Kessler, 2007).

Bulimia Nervosa Whereas anorexia nervosa is charac- terized by forced starvation, bulimia nervosa involves bingeing, consuming large quantities of food, and then purg- ing through vomiting or the use of lax- atives, enemas, or diuretics. Bulimics may cycle through bingeing and purg- ing several times each day. Though the weight of someone with bulimia can remain fairly stable, serious com- plications are just under the surface. Because of frequent contact with the stomach acid in vomit, the throat and teeth are usually damaged and the mouth scarred. Gastric reflux is com- mon. Like anorexia, bulimia is most often diagnosed in wealthier Cauca- sian girls, but the frequently cited low prevalence among ethnic minorities

iStock/Thinkstock

A person suffering from bulimia may binge and purge several times a day. The damage that results from such cycles can include damage to the throat and teeth and scarring of the mouth.

mos82599_06_c06_181-218.indd 192 2/11/16 8:26 AM

193

Section 6.3 Illness in Childhood

and in non-Western countries has been recently challenged (DeLeel, Hughes, Miller, Hipwell, & Theodore, 2009; Smink et al., 2012; Swanson et al., 2011).

Sociocultural variables, including messages from peers and the media, familial influences, low self-esteem, and biological factors have all been suggested as agents of influence in anorexia nervosa and bulimia nervosa (e.g., Polivy & Herman, 2002; Wade et al., 2008). Cer- tainly culture must have a large impact on these eating disorders, since they are traditionally found almost exclusively in areas that hold up thinness as the ideal body type. The finding that prevalence is higher in the United States than in any other country supports this idea. In addi- tion, these disorders are virtually nonexistent in poor parts of South Asia, but exist among the upper classes in Japan and Hong Kong, which are strongly influenced by Western culture (Chisuwa & O’Dea, 2010; Lee, Ng, Kwok, & Fung, 2010). Though some general environmental, cognitive, and biological factors appear to be prerequisite to eating disorders, research that supports any one theory does not exist (Attia, 2010). Consequently, treatment is also multi- faceted, incorporating a combination of behavioral, cognitive, and family treatment.

Binge Eating Disorder Compared to other eating disorders, binge eating disorder has a later onset (Smink et al., 2012). Unlike anorexia and bulimia, this disorder does not involve harmful compensatory behaviors like excessive exercise, purging, and periodic self-starvation. Therefore, those with binge eating disorder are usually overweight. Binge eating disorder is marked by rapidly eat- ing unusually large amounts of food several times per week, leading to physical discomfort. Individuals typically feel shame when they overeat, which leads them to binge while alone. As in the adult population, binge eating disorder among adolescents is the most common eating disorder. It affects between 1.6% and 3.0% of the U.S. teenage population and about 1.2% of adults (Hudson et al., 2007; Stice, Marti, & Rohde, 2013; Swanson et al., 2011). Little is known about the causes of binge eating disorder, though researchers have suggested it is associated with depression or is caused by differences in brain chemicals and hormones (e.g., Gadalla & Piran, 2008).

Section Review Describe three common eating disorders and their behavioral outcomes. What contextual fac- tors could influence the individuals coping with such disorders?

6.3 Illness in Childhood Other than dealing with finicky eaters, many parents do not pay much attention to nutrition and weight, because the consequences for their children usually do not appear until years later. Instead, the biggest health concern among infants and younger children is most often considered the common cold, accounting for about 75% of all childhood illnesses (Schlessel- man, 2006). Colds frequently cause secondary conditions like ear infections (otitis media), which occur with much greater frequency in infants and young children than adults (Monasta et al., 2012). Colds in infants can cause strain on the entire family. Parents have to sit up

mos82599_06_c06_181-218.indd 193 2/11/16 8:26 AM

194

Section 6.3 Illness in Childhood

at night with crying children, leading to increased sleep deprivation, and it can be difficult to find a friend or relative to stay home during the day with a sick child. Doctor’s appoint- ments and missed work add to overall discomfort and stress. In contrast to children from low-income countries, with proper care it is rare that children in the United States experience hearing loss from untreated or frequent ear infections. For the most part, children in wealthy countries emerge from early childhood unscathed by the common cold (Monasta et al., 2012).

Lower-SES families overall are more likely to have health problems and suffer life-long con- sequences than middle- and upper-income families. Lower-income families are more likely to have health problems at birth, to have more chronic conditions like asthma and diabetes, to be hospitalized frequently, to be exposed to poorer air quality, and to experience more noise and more stress (Fletcher & Wolfe, 2014; Hair, Hanson, Wolfe, & Pollak, 2015; Luby, 2015). When these additional circumstances are present, education might not be prioritized as in upper-income households. These circumstances result in a disproportionate number of children from lower-income families missing out on opportunities that go along with high academic achievement.

Asthma Asthma is the most common chronic disease of childhood, affecting 8.3% of children and 7.0% of adults in the United States. It causes breathing airways to become inflamed and con- stricted, leading to shortness of breath, a feeling of tightness in the chest, wheezing and cough- ing. Fortunately, under ordinary conditions it can usually be controlled and does not inhibit physical growth and development in any noticeable way. In fact, paradoxically, it appears that asthma is more common in elite athletes than in the general population (Weiler, Layton, & Hunt, 1998; Weiler & Ryan, 2000). Perhaps lending a clue to its cause, athletes who princi- pally train outdoors have a higher incidence than those who train indoors. Factors that affect severity and responsiveness to medication include tobacco smoke, air pollution and other air contaminants, respiratory infections, and stress (National Heart, Lung and Blood Institute, 2013; Ober, Hoffjan, & Hoffjan, 2006).

Research into the specific causes of asthma is generally inconclusive, though there is likely a complex interaction among environmental and biological variables; a genetic contribution is well established (Barnes, 2011; Belsky et al., 2015). For unknown reasons, prevalence has been rising worldwide. There are significant variations by age, race, sex, where one lives, and income level (National Center for Health Statistics [NCHS], 2014; Thakur et al., 2013). For instance, the prevalence among Hispanic Puerto Ricans is triple that of Hispanic Mexican Americans, as depicted in Figure 6.4. Asthma is more widespread in wealthier countries, but leads to higher mortality in developing countries. Prevalence increases in groups that move from rural areas to more urban areas, implying that there is some kind of effect related to industrial development. Despite this implication, Mexican children born in the United States have a higher rate of asthma than those born in Mexico, even though there are stronger envi- ronmental safeguards in the United States (Eldeirawi et al., 2009).

mos82599_06_c06_181-218.indd 194 2/11/16 8:26 AM

195

P e rc

e n

ta g

Fe m

al e

M al e

Ch ild

(A ge

< 18

)

Ch ild

(A ge

1 8+

) To

ta l

8.3

6.2

4.7

14.6

5.9

9.9

7.4

5.8

7.3

Pu er

to R

ica n

To ta

l H isp

an ic

Bl ac

k no

n- Hi

sp an

W hi te

n on

-H isp

an ic

O th

er n

on -H

isp an

M ex

ica n/

M ex

ica n Am

er ica

* As a subset of Hispanic

7.0 8.3

Section 6.3 Illness in Childhood

Figure 6.4: Asthma prevalence in the United States, 2013

Scientists have few clues to explain the wide demographic variation in asthma prevalence.

Source: Adapted from National Health Interview Survey, National Center for Health Statistics, CDC , 2014.

P e rc

e n

ta g

Fe m

al e

M al e

Ch ild

(A ge

< 18

)

Ch ild

(A ge

1 8+

) To

ta l

8.3

6.2

4.7

14.6

5.9

9.9

7.4

5.8

7.3

Pu er

to R

ica n

To ta

l H isp

an ic

Bl ac

k no

n- Hi

sp an

W hi te

n on

-H isp

an ic

O th

er n

on -H

isp an

M ex

ica n/

M ex

ica n Am

er ica

* As a subset of Hispanic

7.0 8.3

Diabetes On average, diabetes has much more serious consequences than asthma. It occurs when high levels of sugar in the blood (glucose) are not regulated properly by the body’s normal systems. A long-term scientific projection foresees a near doubling of the diabetic population by the year 2050 (Boyle, Thompson, Gregg, Barker, & Williamson, 2010). There are two main kinds of diabetes. Type 1 diabetes is a somewhat rare (less than 0.5% of the population), a lifelong condition that probably has a strong genetic link (Noble & Erlich, 2012). In contrast, the sharp increase in type 2 diabetes is attributed to the parallel rise in obesity and overweight.

In past generations, type 2 diabetes was seen almost exclusively in adults—and even then, not usually until past the age of 40 (NIH, 2011). Due to increasing weight and decreasing amounts of physical activity, many young children are now at risk. It is predicted that 1 in 3 children who were born in the United States in 2000 will develop the disease in their lifetimes, com- pared to 1 in 10 people who are currently affected (Boyle et al., 2010; NIH, 2011). Certain races and ethnicities, including blacks, Hispanics, American Indians, and Asian Americans are more likely to develop type 2 diabetes than whites (see Figure 6.5). However, after two decades of steadily increasing prevalence, the overall rate in the United States has begun to plateau. One major exception is the Hispanic population, which has continued to see its preva- lence climb (CDC, 2015b). Increasing rates of obesity and an aging population has swollen rates of type 2 diabetes around the world as well (Danaei et al., 2011; Pierce, 2013).

mos82599_06_c06_181-218.indd 195 2/11/16 8:26 AM

196

Type 1 diabetes Type 2 diabetes

Rate (per 100,000 per year)

0 20 3010 40 50

All

Non-Hispanic white

Ages 9 & under

Ages 10−19

African Americans

Hispanics

Asians/Pacific Islanders

American Indians

All

Non-Hispanic white

African Americans

Hispanics

Asians/Pacific Islanders

American Indians

Section 6.3 Illness in Childhood

Diabetes can affect virtually every body system. It doubles the risk of dying at any particular time and is reported to be the seventh overall cause of death in the United States; it contrib- utes to cause of death in even more cases (CDC, 2015b). Obesity and lack of physical activity are by far the strongest risk factors for type 2 diabetes. The disease is associated with a host of debilitating complications that affect health and secondary aging, including cardiovascular disease, stroke, and kidney failure. There is mounting evidence that links diabetes to cogni- tive impairment and dementia as well (Chung et al., 2015; Qizilbask et al., 2015). Other long- term complications include blindness, limb amputations, and damage to the nervous system.

Figure 6.5: Rates of new cases of type 1 and type 2 diabetes, by age and race/

ethnicity

Rates of type 1 and type 2 diabetes vary significantly as a function of age and race/ethnicity. The percentage of cases that are type 2 increases substantially beginning in preadolescence.

Source: Centers for Disease Control and Prevention. (2014). National diabetes statistics report: Estimates of diabetes and its burden in the United States [Figure on top of page 4]. Atlanta, GA: U.S. Department of Health and Human Services. Retrieved from http://www.cdc.gov/diabetes/pubs/statsreport14/national-diabetes-report-web.pdf

Type 1 diabetes Type 2 diabetes

Rate (per 100,000 per year)

0 20 3010 40 50

All

Non-Hispanic white

Ages 9 & under

Ages 10−19

African Americans

Hispanics

Asians/Pacific Islanders

American Indians

All

Non-Hispanic white

African Americans

Hispanics

Asians/Pacific Islanders

American Indians

mos82599_06_c06_181-218.indd 196 2/11/16 8:26 AM

http://www.cdc.gov/diabetes/pubs/statsreport14/national-diabetes-report-web.pdf

197

Section 6.4 Maximizing Childhood Health Outcomes

For most people, maintaining a normal weight through proper nutrition and exercise can control diabetes and its costs. In some cases, lifestyle changes can even reverse the disease, especially within the first 5 years of diagnosis (Brethauer et al., 2013; Karter, Nundy, Parker, Moffet, & Huang, 2014). It has also been suggested that reversing diabetes through bariatric surgery or diet should be the goal of disease management (e.g., Steven, Lim, & Taylor, 2013).

6.4 Maximizing Childhood Health Outcomes Though proper diet and exercise are at the forefront of creating a healthy lifestyle, there are other factors too. In sharp contrast to the industrialized world, it is commonplace in parts of Africa and South Asia to die of diarrheal diseases, malaria, or AIDS. Creating optimal health outcomes in those low-income countries include basic measures that we often take for granted. This section will explore some of the contrasting interventions in health and longev- ity that we see around the world.

Childhood Mortality and Prevention Efforts After a steep drop in infant mortality (death before 1 year of age) during the first half of the 1900s, the creation of Medicaid in 1965 provided an added boost. Increased access to medical care contributed to a 41% drop in deaths during the neonatal period and a 14% drop in post- neonatal deaths (months 2–12) during the 1970s (Pharoah & Morris, 1979). Infant mortality continued to decline in the last decade of the last century, primarily because of the significant reduction in the rate of SIDS (Centers for Disease Control and Prevention, 2015e). However, the United States still trails many other technologically advanced countries in rates of death, sometimes by a wide margin. For instance, the rate of infant mortality is more than one third higher than in the United Kingdom, more than double the rate in Hong Kong, and nearly three times as high as Iceland and Japan (Central Intelligence Agency [CIA], 2015). Although part of the reason the rate in the United States is relatively high is due to inconsistent pre- and post- natal care, overall the large discrepancies have been poorly understood.

An important new analysis by Chen, Oster, and Williams (2015) compared the rate of infant mortality in the United States to Austria and Finland. All three countries have similar report- ing methods (some countries report mortality among extremely-low-birth-weight infants as miscarriages), but the United States has a steeper rate of mortality. Though the three coun- tries were found to have similar rates of neonatal mortality, postneonatal deaths in the United States are considerably higher. That is, during the first month or so, rates are similar in the United States, Finland, and Austria; but as infants get older the gap widens.

Further analysis shows that much of the difference is associated with the economic profile of mothers. Whereas children born to high SES mothers in the United States have comparable out- comes to Austrian and Finnish children, those born to low SES mothers in the United States are at considerable disadvantage. It is suggested that much of the disadvantage experienced by low SES children is due to disparate access to medical technologies (Chen et al., 2015).

mos82599_06_c06_181-218.indd 197 2/11/16 8:26 AM

198

U n

d e r-

fi v e m

o rt

a li ty

r a te

, 1 9 9 0 a

n d

2 01

(D e a th

s p

e r

1 ,0

0 0 l iv

e b

ir th

s )

100

125

150

175

200

Su b-

Sa ha

ra n

Af ric

So ut

he rn

A sia

O ce

an ia

Ca uc

as us

a nd

Ce nt

ra l A

sia

So ut

he as

te rn

As ia

W es

te rn

A sia

No rth

er n Af

ric a

La tin

A m

er ica

a nd

th e

Ca rib

be an

Ea st er

n As

De ve

lo pi ng

re gi on

De ve

lo pe

d re

gi on

W or

1990 2015 projection

1990

2015 Target

2015 projection

179

126

100

15 6

Section 6.4 Maximizing Childhood Health Outcomes

In response to continued poor outcomes in poorer countries, the United Nations established the Millennium Development Goals, aiming to reduce the unacceptably high under-5 mortal- ity rate by two thirds between 1990 and 2013 (United Nations, 2015). Only partly because of their large populations, just five countries account for half of early childhood deaths: India, Nigeria, Democratic Republic of the Congo, Pakistan, and China. However, worldwide, the annual rate of under-5 mortality dropped by half from 1990 to 2013. Though a vast improve- ment from when the Millennium Project began, approximately 17,000 children still die each day from mostly preventable causes, or nearly 1 out of 20 live births. Afghanistan and parts of Sub-Saharan Africa have the world’s highest rates of infant mortality, where 1 in 10 children do not live to see their fifth birthdays.

Although the goal of a two thirds reduction in child mortality worldwide is out of reach at the moment because of lack of progress in Sub-Saharan Africa, Southern Asia, and Oceania, there is nevertheless substantial good news. For instance, during the decade from 2000 to 2009, the decline in child mortality accelerated, compared with the previous decade (Figure 6.6). Gains

Figure 6.6: Mortality rate for children under 5 worldwide, 1990 and 2015

Survival rates began to accelerate in 2000, continuing the substantial gains of the previous decade. Nevertheless, the goal of a two thirds reduction in mortality of children under 5 is unlikely to be met by 2015.

Source: Adapted with permission from the Millennium Development Goals Report, United Nations, 2015.

U n

d e r-

fi v e m

o rt

a li ty

r a te

, 1 9 9 0 a

n d

2 01

(D e a th

s p

e r

1 ,0

0 0 l iv

e b

ir th

s )

100

125

150

175

200

Su b-

Sa ha

ra n

Af ric

So ut

he rn

A sia

O ce

an ia

Ca uc

as us

a nd

Ce nt

ra l A

sia

So ut

he as

te rn

As ia

W es

te rn

A sia

No rth

er n Af

ric a

La tin

A m

er ica

a nd

th e

Ca rib

be an

Ea st er

n As

De ve

lo pi ng

re gi on

De ve

lo pe

d re

gi on

W or

1990 2015 projection

1990

2015 Target

2015 projection

179

126

100

15 6

mos82599_06_c06_181-218.indd 198 2/11/16 8:26 AM

199

Section 6.4 Maximizing Childhood Health Outcomes

have been made in combating poverty, increasing primary school education, addressing dis- ease and mortality due to AIDS and malaria, providing greater access to clean drinking water, and, perhaps surprisingly, proper ventilation of indoor cook stoves. Among children under 5 worldwide, unsanitary conditions and lack of clean drinking water contribute to the 15% of deaths caused by diarrheal diseases. In comparison, deaths due to diarrheal diseases in the United States account for less than 0.1% of deaths in children younger than 5 (CDC, 2015e).

Immunizations One of the easiest ways to protect health and wellness beginning as early as infancy is to pro- vide immunizations. In both high and low income countries, their widespread use has made a dramatic difference in the health of populations. They are responsible for the near elimina- tion of diseases such as polio and measles and are the best defense against viruses (there are as yet no cures for viruses; treatments focus on relief of symptoms and the reduction of severity). After the widespread use of measles vaccine began in the 1960s, the number of cases was reduced from three quarters of a million to fewer than 100 in 2012 (CDC, 2015d). However, a 2015 measles outbreak at a major theme park in California was the latest in a series of problematic outbreaks of diseases that have been designated as eliminated. (Elimi- nated means there is zero incidence of a disease in a defined geographic area, like polio in most countries; eradicated refers to zero worldwide incidence, like smallpox.) As Figure 6.7 shows, the number of cases of measles in 2014 was more than double the highest rate of any year in the previous 20 (CDC, 2015d).

Some media reports have questioned the safety of immunizations and such instances have elevated lay people as experts instead of focusing exclusively on scientific consensus. Similar outbreaks have occurred with whooping cough, chicken pox, and other diseases. The upsurge can be traced to Andrew Wakefield’s fraudulent report in the prestigious journal Lancet (since retracted) about a purported link between vaccines and autism. Although the evidence regarding the benefit of vaccines remains scientifically unequivocal, celebrity rhetoric and erroneous media reports continue to feed public misconceptions, which have reduced the rate of immunization coverage (Majumder, Cohn, Mekaru, Huston, & Brownstein, 2015).

mos82599_06_c06_181-218.indd 199 2/11/16 8:26 AM

200

R e p

o rt

e d

m e a s le

s c

a s e s (

th o

u s

a n

d s

)

14.0 16.0

1958

Year 1968 1978 1988 1998 2007 2014

400.0 200.0 100.0 80.0 60.0 40.0 20.0 18.0

8.0 10.0 12.0

4.0 6.0

2.0 1.8

1.4 1.6

1.2 1.0 0.8

0.4 0.6

0.2 0.1

0.08 0.06 0.04 0.02

600.0 800.0

Section 6.4 Maximizing Childhood Health Outcomes

Figure 6.7: Measles cases in the United States, from 1958 to the first part of

2015

The incidence of measles decreased dramatically after vaccines were distributed widely, but success sometimes breeds complacency, as indicated by temporary spikes indicating outbreaks.

Source: Adapted from Koo et al. (1993), Hall-Baker et al. (2010), and CDC (2015d).

R e p

o rt

e d

m e a s le

s c

a s e s (

th o

u s

a n

d s

)

14.0 16.0

1958

Year 1968 1978 1988 1998 2007 2014

400.0 200.0 100.0 80.0 60.0 40.0 20.0 18.0

8.0 10.0 12.0

4.0 6.0

2.0 1.8

1.4 1.6

1.2 1.0 0.8

0.4 0.6

0.2 0.1

0.08 0.06 0.04 0.02

600.0 800.0

Psychology in Action: Global Burden of Disease

We have only recently begun to use sophisticated health metrics (“big data”) to look more closely at demographic and geographic differences in health and wellness. Since 1990, the international Global Burden of Disease (GBD) Study, headquartered at the Institute for Health Metrics and Evaluation (2015) at the University of Washington, has tracked the annual total of 240 causes of death worldwide in 187 countries. The study is a comprehensive collabora- tion among more than 500 researchers from over 300 institutions in 50 countries. The Global

(continued)

mos82599_06_c06_181-218.indd 200 2/11/16 8:26 AM

201

Section 6.4 Maximizing Childhood Health Outcomes

Burden of Disease is calculated as the gap between current health status of a group and the age at which a healthy person within that group should be able to live, free of disease and disability.

An important statistical consideration in the GBD research concerns a quantified quality of life measure called disability-adjusted life years, or DALY (see Table 6.1). For instance, from the standpoint of a personal and global burden, living with a respiratory illness for decades contributes to many more DALYs lost than dying prematurely of pneumonia at age 80. Further, although physical and mental pain are not causes of death, they have very high DALYs. This kind of information helps in planning intervention and prevention efforts.

Table 6.1: Measuring the global burden of disease

Rank Ten leading diseases and injuries, 2010 Ten leading risk factors, 2010

Cause DALYsa Cause DALYsa

1 Ischemic heart disease

129,795,000 High blood pressure

173,556,000

2 Lower respiratory tract infections

115,227,000 Tobacco smoking, including expo- sure to second- hand smoke

156,838,000

3 Stroke 102,239,000 Household air pollution from solid fuels

108,084,000

4 Diarrhea 89,524,000 Diet low in fruit 104,095,000

5 HIV-AIDS 81,549,000 Alcohol use 97,237,000

6 Malaria 82,689,000 High body mass index

93,609,000

7 Low back pain 80,667,000 High fasting plasma glucose level

89,012,000

8 Preterm birth complications

76,980,000 Childhood underweight

77,316,000

9 Chronic obstructive pulmonary disease

76,779,000 Exposure to ambi- ent particulate- matter pollution

76,163,000

10 Road-traffic injury 75,487,000 Physical inactiv- ity or low level of activity

69,318,000

a Disability-adjusted life-years (DALYs)

Source: Adapted from Murray, C. J. L., & Lopez, A. D. (2013). Measuring the global burden of disease. New England Journal of Medicine, 369, 448–457

Psychology in Action: Global Burden of Disease (continued)

(continued)

mos82599_06_c06_181-218.indd 201 2/11/16 8:26 AM

202

Section 6.5 Illness and Disease in Adulthood

An often-cited key moment in the GBD research occurred when it was discovered that indoor air pollution in Rwandan homes was the leading risk factor for premature death and disabil- ity in that country (GBD 2013 Mortality and Causes of Death Collaborators, 2015). Almost immediately, Rwanda’s minister of health began to distribute one million clean-burning cook stoves to low-income, rural households who were living in poorly ventilated huts. Millions of lives have since improved. Because of the previously unknown data from the GBD, Mexico has changed its health care policies, China has begun work on reducing outdoor air pollution, and Iran has instituted policies and trainings aimed at reducing traffic accidents, which had been their leading cause of death and disability. In Columbia, a violent culture where drug traffick- ing was thought to be the primary contributor to deaths, the GBD found that violence and murders spiked near paydays. As a result, the government instituted restrictions on the sale of liquor and guns, reducing murders by about half.

The GBD data also allow us to better understand why certain countries fare better than others on measures of health and safety. For instance, for reasons still unknown, we know that twice as many people in France die from falls as Spain, even though they have similar populations; the United States and the United Kingdom have similar mortality rates for falls, but the rate of poisoning death in the United Kingdom is half of the United States. Uncovering best practices in Spain and the United Kingdom will lift the burden of disease in France and the United States. Learning that people in China had a much higher rate of drowning compared to people who lived in similar situations elsewhere initiated widespread prevention strategies. As a result, drowning deaths in China dropped by two thirds from 1990 to 2013.

Finally, these data can also be used to calculate DALY’s for a group within a country. In the United States, for instance, health among men over 30 is associated with high intake of pro- cessed meat and low intake of fruit. It is suggested that reversing this pattern will go a long way in preventing diseases of the circulatory system, like heart attacks and stroke. Overall, the GBD collaborators hope these newborn resources will create competition to improve health science and guide investment decisions.

Psychology in Action: Global Burden of Disease (continued)

6.5 Illness and Disease in Adulthood By middle adulthood, despite the perceptions of many young people, most adults are healthy. However, diseases that are typically associated with older people begin to appear. This is reflected in data that show that cancer and cardiovascular disease replace accidents as the leading causes of death beginning in the mid-40s. These common illnesses of adulthood will be addressed in this section.

Section Review Summarize major health concerns during childhood that affect survival rates into adulthood.

mos82599_06_c06_181-218.indd 202 2/11/16 8:26 AM

203

Section 6.5 Illness and Disease in Adulthood

Sexually Transmitted Infections and Diseases There are more than 25 different types of STDs, which tend to have unpredictable long-term trends (Aral, Fenton, & Holmes, 2007; Child Trends Databank, 2015). If left untreated, sexu- ally transmitted infections (STIs) eventually turn into sexually transmitted diseases (STDs). Bacterial infections like gonorrhea, syphilis, and the most common, chlamydia, gen- erally run a short course and do not have lasting long-term consequences if routinely treated with antibiotics. On the other hand, if left untreated, they can have devastating effects, includ- ing infertility, blindness, and death.

In contrast to bacterial infections, viruses almost always have lifelong consequences. They include genital herpes, the human papillomavirus (HPV) (also known as genital warts), and the human immunodeficiency virus (HIV), which is the virus that causes acquired immune deficiency syndrome (AIDS). AIDS is a chronic, life-threatening disease that dam- ages the immune system, making a person less able to fight off a variety of illnesses and infec- tions, including pneumonia. The virus is transmitted from one infected person to another by sexual contact (including oral sex), infected blood, sharing HIV-contaminated needles, and from mother to child during birth and through breastfeeding—a tremendous problem in developing countries. (Also see Chapter 4.) HIV does not spread through ordinary contact like shaking hands, hugging, or kissing.

Due to large cultural and international differences, demographic issues are a prominent fea- ture of AIDS education and prevention. For example, because of increased education and awareness, AIDS/HIV is no longer in the top 20 leading causes of death for the United States. However, it is the sixth leading cause of death among middle-aged black women in the United States, and remains the sixth leading cause of death worldwide. Furthermore, though there have been tremendous gains, it remains the leading cause of premature death in 20 African countries (CDC, 2015e; GBD 2013 Mortality and Causes of Death Collaborators, 2015; WHO, 2014). While there is no cure for HIV, early adherence to antiretroviral therapy not only pre- vents disease-related conditions, but new evidence shows it prevents other, non-AIDS-related diseases like cardiovascular disease and cancer (NIH, 2015b).

Smoking and Use of Other Tobacco Not all environmental aging factors are within an individual’s control. For example, coal min- ers are susceptible to lung disease as a result of inhaling large amounts of coal dust over a long period of time. In contrast, smoking is one of the most dangerous choices anyone can make. It significantly increases incidence of cardiovascular diseases, cancer, and lung diseases, which are the three most frequent causes of death in the United States (CDC, 2015e). Use of tobacco in general is linked to cancers of the lung, larynx, mouth, brain, esophagus, bladder, kidney, pancreas, and cervix. Smokers are 14 times more likely to die from lung cancer than non- smokers and twice as likely to die from a heart attack. When a pregnant woman smokes, it increases the chances of a stillbirth or having a low-birth-weight baby, and may have a nega- tive effect on the cognitive performance of the newborn (USDHHS, 2010).

People who do not smoke average ten more years of life than those that do, and are generally healthier at every age as well (Jha et al., 2013). In addition to increasing overall mortality, smoking negatively affects nearly every aspect of aging and development. It accelerates wrin- kling and contributes to bone loss (and therefore fractures), damages cells that line the heart,

mos82599_06_c06_181-218.indd 203 2/11/16 8:26 AM

204

Section 6.5 Illness and Disease in Adulthood

causes an increase in lung infections, accelerates decline in dental and sexual health, and causes complications when recovering from nearly any ailment. Therefore, quitting smoking is usually the single most significant change a person can make to avoid disease, disability, and death.

Nonsmokers who breathe secondhand smoke are also at risk. Sometimes called “passive smoking,” secondhand smoke carries over 250 toxic chemicals. It is associated with cardio- vascular disease, cancer, asthma complications, and other diseases (Lubick, 2011). The U.S. Department of Health and Human Services reports that, “There is no risk-free level of sec- ondhand smoke exposure. Even brief exposure can be dangerous” (USDHHS, 2006). Some are also concerned about “third-hand smoke,” or the residue left on various objects like food and doorknobs, but exposure to the potential toxic effects from these circumstances are difficult to separate from second-hand smoke.

A major study provides one more piece of evidence that implicates tobacco—this time in relation to cognitive decline and aging (Dregan, Stewart, & Gulliford, 2012). A study of nearly 8,800 individuals found an association between smoking and three kinds of brain functioning, including tests for memory and global cognition. According to the authors, “smoking emerged as the most consistent predictor of cognitive decline” (Dregan, Stewart, & Gulliford, 2012, p. 7, emphasis added). This information suggests that we can have secondary control over sig- nificant aspects of development over the lifespan—that our actions influence elements of our development.

It is estimated that 17.8% of adults living in the United States currently smoke, which is an all- time low (Auld et al., 2014). Nevertheless, smoking causes 440,000 deaths every year (about 1 out of every 5) and is responsible for another 16 million people who have smoking-related diseases. Smoking rates are significantly related to socioeconomic status (SES), with those who can least afford a pack of cigarettes smoking the most. The overall use of tobacco has been declining in other industrialized countries, but there has been mixed results in prevent- ing smoking in the poorest nations (Britton, 2015). About half of men and 1 in 10 women use tobacco products in low-income countries. Bangladesh and India have the highest rates of use of smokeless tobacco (and the highest rate among women). Not coincidentally, these two countries also have the highest rates of oral cancer in the world. The World Health Organiza- tion calls tobacco use the “leading cause of death, illness and impoverishment” in the world; it is the only substance that kills its users when consumed as intended (WHO, 2015c).

A potential new concern has arisen with the advent of e-cigarettes, a form of flavored nicotine that is inhaled through an aerosol or vaporizing process (hence the more global term “vap- ing”). It has been suggested that e-cigarettes provide safer delivery of nicotine because they exclude the toxic effects of tobacco combustion. Additionally, e-cigarettes are purported to eliminate the harmful effects of secondhand smoke by exhausting only vapor. This technol- ogy is considered an advantage for smokers who wish to quit, but, for novice users, may be a problematic.

Though evidence remains tenuous that substances like nicotine lead to use of stronger psy- choactive substances like cocaine, the “Gateway Hypothesis” is nevertheless often cited as a reason to be concerned (Kandel & Kandel, 2014). Though not necessarily a gateway, vaping nevertheless allows users to increase their intake of nicotine since many jurisdictions have not yet decided how to restrict its use in the same way that smoking has been regulated.

mos82599_06_c06_181-218.indd 204 2/11/16 8:26 AM

205

Section 6.5 Illness and Disease in Adulthood

While it is suggested that vaping will eventually eliminate the toxic effects of tobacco, prelimi- nary data show that greater numbers of young people expose themselves to nicotine through e-cigarettes (e.g., Bostean, Trinidad, & McCarthy, 2015). This development is an increasing concern because nicotine interferes with brain development from the fetal period through at least early adulthood (Yuan, Cross, Loughlin, & Leslie, 2015).

Cancer Among smokers and nonsmokers alike, the incidence of cancer increases with age, partly due to simple expo- sure of time. In addition, aging cells are thought to be more vulnerable to car- cinogens (cancer-causing substances) (Anisimov, Sikora, & Pawelec, 2009). Overall cancer death rates continue to decline in the United States among all racial and ethnic groups (National Cancer Institute, 2013a). Skin cancer is the most common form in the United States, but lung cancer is by far the biggest killer among men and women alike. Besides skin cancer, breast can- cer is the most common form of cancer among women and prostate cancer is the most common form among men. A significant proportion of cancers are cured now; early detection is key to recovery (CDC, 2014c).

Skin Cancer Milder types of skin cancer include squamous cell and basal cell. These forms often start out as reddish patches or feel like scabs that do not heal. Treatment usually takes only a few moments in a dermatologist’s office. With proper intervention, they pose little risk to long- term health.

Melanoma is the most dangerous type of skin cancer. It is quick to metastasize (spread) to lymph nodes and distant body systems, where recovery becomes much more difficult. Mela- nomas may first appear to be benign moles or spots on the skin, and, as with many forms of cancer, early detection is key to prevention. If you know your ABCDEs (asymmetry, border, color, diameter, and elevation) and have suspicious areas examined, the chance of complete recovery from skin cancer is excellent. That is, if skin cancer remains localized, the chances of long-term survival (5 years and more) is 98%; if lack of detection or treatment has allowed the cancer to metastasize, survival rates drop to 15% (ACS, 2012).

Though melanoma is much less common among those with darker skin tones, it is much more frequently fatal (Hu, Soza-Vento, Parker, & Kirsner, 2006). These consequences may be due to an assumption of low risk in these groups, resulting in a lack of knowledge and less alarm when risk factors appear.

GIRAND/BSIP/Superstock

Knowing early signs of detection for melanoma is key to improving your chances of recovery. Look out for issues regarding asymmetry, border, color, diameter, and elevation.

mos82599_06_c06_181-218.indd 205 2/11/16 8:26 AM

206

Section 6.5 Illness and Disease in Adulthood

Breast Cancer Except for skin cancer, breast cancer is the most common form of cancer in women of all races and ethnicities. Of women born today, 1 in 8 will be diagnosed with cancer during their life- times; the median age of diagnosis is 61 years (National Cancer Institute, 2013b). However, breast cancer is nowhere near the death sentence it is sometimes thought to be. Among all women diagnosed with breast cancer, approximately 90% are expected to survive for at least 5 years after the diagnosis. And highlighting the value of early detection, the 5-year survival rate when the cancer remains localized is 99% (ACS, 2015).

A routine mammogram is the accepted standard for the early detection, because most non- invasive malignancies can be cured if they are caught early. The American Cancer Society recommends that women make their own informed decisions to screen for cancer if between the ages of 40 and 44, and to begin annual mammograms at age 45. However, not every- one agrees, as early screening can result in unnecessary intervention. Examining this issue is complicated because there are many emotional anecdotes on both sides (see, for example, Otto & Blecher, 2014). Controversies exist regarding breast self-examinations as well, since statistical evidence shows no drop in mortality and an increase in unnecessary treatments (Fuller, Lee, & Elmore, 2015; Kösters & Gøtzsche, 2008; Nelson et al., 2009). Nevertheless, women of all ages should conduct breast self-examinations to at least become familiar with their normal anatomy, which could help them identify irregularities.

Prostate Cancer The prostate is a small gland in the male reproductive system that produces semen and trans- ports sperm. Like breast cancer, test inaccuracies have led to different opinions about the value of screening for lower-risk groups. Although increasing use of blood tests may identify more prostate cancers, there is discussion about whether all prostate cancers need to be actively treated. While some types of prostate cancer are aggressive and can spread quickly, other types grow slowly and may need minimal or no treatment. And physicians cannot necessar- ily tell the difference. Because radiation and surgical treatments for prostate cancer can have serious side effects, current research is addressing when the use of interventions is worth- while. Protocol for some patients now includes deferring treatment with “watchful waiting” (observation) or “active surveillance” (blood tests and other exams). These approaches may allow men who have the type of prostate cancer that will never cause disability or death to avoid radical treatment while still ensuring that men with aggressive disease are treated in time (Bill-Axelson et al., 2014; Shao, Albertsen, Shih, Roberts, & Lu-Yao, 2011).

Diseases of the Cardiovascular System Though adults are often most afraid of cancer, more deaths in the U.S. and around the world can be attributed to cardiovascular disease (related to the heart and blood vessels) than any other cause. More people die from these diseases than all forms of cancer combined, accounting for roughly 31% of all U.S. deaths and 25% worldwide (CDC, 2015e). Although cardiovascular diseases like arteriosclerosis (hardening of the arteries) and hypertension (high blood pressure) can affect people of all ages, the heart is more susceptible to disease as people get older. Fat and plaque build up on arterial walls and the heart loses its elasticity and ability to respond to changes in blood pressure (Lakatta & Levy, 2013). The consequences of these conditions are heart attack and stroke. Risk factors are only partly determined by

mos82599_06_c06_181-218.indd 206 2/11/16 8:26 AM

207

Section 6.5 Illness and Disease in Adulthood

genetics. Protection is strongly associated with exercise and nutrition habits, including con- trolling serum cholesterol by limiting saturated fat intake. Other recommendations include refraining from smoking, controlling diabetes, drinking alcohol only in moderation, and avoiding the use of illicit drugs.

Chronic Obstructive Pulmonary Disease Primarily because of smoking, chronic obstructive pulmonary disease (COPD) is the third leading cause of death in the United States and fourth leading cause of death worldwide. When people smoke, toxins cause holes to form in the lungs, leading to a reduction in the amount of oxygen and carbon dioxide that gets exchanged. Small airways that are used when exhaling are also destroyed, thereby obstructing the lungs from completely expelling carbon dioxide and resulting in shortness of breath. This irreversible condition is called emphysema, which is the most common form of COPD. A percentage of emphysema is caused by air pollution, including secondhand smoke, but about 85% of cases are due to smoking. Though COPD is a leading cause of death and disability, only 74% of smokers and 65% of all adults have even heard of COPD (NIH, 2012).

At first, symptoms of COPD only occur upon physical exertion. It gradually becomes harder and harder to breathe as more tissues become obstructed. Treatments are available that tem- porarily alleviate the severity of breathing problems, but the disease remains degenerative. In later stages, people with COPD can find it difficult to eat, since there is a coordinated effort between breathing, chewing, and swallowing. Oxygen therapy may assist in some cases, but even pure oxygen cannot repair deteriorating membranes that simply cannot carry the oxy- gen into the bloodstream. If related fatal consequences (e.g., heart attack) do not occur, the disease will eventually prevent breathing altogether and cause death.

Degenerative Diseases of the Brain Differentiating among the many kinds of dementia is important for research and treatment paths, but most forms are behaviorally similar (Sabbagh et al., 2009). The two most common degenerative brain diseases, Parkinson’s and Alzheimer’s, can only be definitively diagnosed postmortem.

Dementia Dementia is a broad term that refers to an abnormal rate of deterioration of the brain and mental functioning. Physical changes, including shrinkage of brain tissue, cause disturbances in memory, attention, and ability to think and communicate clearly. Although dementia is progressive, it is not an inevitable part of aging. It is estimated that the prevalence of demen- tia among 85-year-olds is about 30%; after age 85, prevalence rises an average of 2.6% per year in women and 1.8% in men, reflecting consistent evidence that women with dementia outnumber men by a substantial proportion. Regardless, a sizeable proportion of people over 100 years of remain cognitively intact (Lucca et al., 2015; Perls, 2006).

Early signs of dementia are often ignored. Solving problems that were formerly routine, such as balancing a budget and operating electronic devices, becomes more challenging. During the middle stages of dementia, lack of self-care and hygiene become noticeable. Personality

mos82599_06_c06_181-218.indd 207 2/11/16 8:26 AM

208

Section 6.5 Illness and Disease in Adulthood

changes could include melancholy, explosiveness, or becoming stubborn. Memory loss becomes more dramatic and there are noticeable deficits in the ability to plan and organize. In late-stage dementia, people lose awareness and the ability to care for themselves. Physi- cal skills deteriorate to the point that many eventually lose basic abilities like walking or swallowing. Differentiating among the many kinds of dementia is important for research and treatment paths, but most forms are behaviorally similar (Sabbagh et al., 2010). The two most common degenerative brain diseases, Parkinson’s and Alzheimer’s, can only be definitively diagnosed postmortem.

There is consistent evidence that remaining physically active provides some protection against the onset and progression of dementia; evidence is less conclusive about the benefits of cognitive training and remaining socially active, but both appear to delay symptoms of dementia. Overall, there appears to be no definitive interventions that can predict an absence of neurodegenerative diseases (Bahar-Fuchs, Clare, & Woods, 2013; Blondell, Hammersley- Mather, & Veerman, 2014; Iso-Markku, Waller, Kujala, & Kaprio, 2015; Kuiper et al., 2015). Like health concerns in general, risk factors for dementia also include hypertension, obesity, diabetes, and the use of tobacco products (Qiu, Kivipelto, & von Strauss, 2009).

Parkinson’s Disease Parkinson’s disease is the second most common neurodegenerative disease. It is caused by the degeneration of neurons that produce dopamine in the brain. Initial symptoms include tremors and shaking, stiff joints, slowed movement, and problems with balance and posture. It usually progresses to difficulty in speaking and expression, and diminished smiling and blinking (Massano & Bhatia, 2012). Though estimates have varied widely in research, the dis- ease leads to Parkinson’s dementia in at least 30% of cases (Aarsland, Andersen, Larsen, Lolk, & Kragh-Sørensen, 2003). It is an incurable disease, but some of the physical symptoms can be treated. Two of the best-known sufferers of Parkinson’s disease are former heavyweight- boxing champion Muhammad Ali and popular actor Michael J. Fox.

Alzheimer’s Disease Alzheimer’s disease accounts for an estimated 75% of dementia cases and is the sixth lead- ing cause of death in the United States among those 65 years of age and older (CDC, 2015e; Qiu et al., 2009). Alzheimer’s probably develops as a function of multiple causes. Like other forms of dementia, healthy brain tissue deteriorates, taking with it the network of knowl- edge and memories. (See Figure 6.8 for a comparison of a healthy brain and one affected by advanced Alzheimer’s disease.) In addition to a shrunken brain, there are two hallmarks that identify Alzheimer’s. Amyloid plaques are deposits that clump inside of blood vessels. These clumps may spread, destroying more brain tissue. There are also twisted fibers, called neu- rofibrillary tangles, which build up inside of neurons. The tangles interfere with the ability of cells to communicate and may cause healthy neurons to die. While everyone who dies of Alzheimer’s has plaques and tangles, not everyone with plaques and tangles has dementia, which complicates understanding of the disease (Serrano-Pozo, Frosch, Masliah, & Hyman, 2011). Like Parkinson’s and dementia, there are no preventive efforts that are predictably successful.

mos82599_06_c06_181-218.indd 208 2/11/16 8:26 AM

209

healthy brain

advanced alzheimer’s

Section 6.5 Illness and Disease in Adulthood

The MIND diet (Mediterranean-DASH diet intervention for neurodegenerative delay), has recently been found to have a signifi- cantly positive effect on the neurodegen- eration of Alzheimer’s disease. The MIND diet combines the DASH diet, which lowers blood pressure among people with hyper- tension, with a Mediterranean diet, which is associated with lowered risk of cardiovascu- lar disease (Morris et al., 2015a). The MIND diet includes daily servings of nuts, whole grains, vegetables, and one glass of wine. Beans, poultry, and berries are consumed at least two times each week and fish at least once. Foods containing large concentrations of saturated fat, including butter, cheese, fried foods, and red meat, are avoided. Over- all, adhering to any of the three diets was significantly associated with improved cog- nitive function over several years.

To study the effects of the various diets on Alzheimer’s disease, Morris and her colleagues fol- lowed 923 adults between 58 and 98 over an average of 4.5 years (Morris et al., 2015b). All three diets were effective in reducing the risk of Alzheimer’s disease. The MIND and Mediter- ranean diets were associated with a 53% reduced risk and the DASH diet reduced risk by 39% over the time the group was studied. However, a surprising finding was that only moderate adherence to the MIND diet was effective in reducing risk of Alzheimer’s disease risk by 35%, whereas those who moderately conformed to the other two diets did not see a lowered risk.

Drugs can only sometimes be helpful. They improve concentration and slow the progression of memory loss and confusion, but they only work for a limited time. Alzheimer’s disease remains progressive and fatal. There is often hope for alternative treatments, but none have yet passed the standards of scientific study. Some early drug trials have been successful in shrinking amyloid plaques, but there has been no measureable improvement in cognition.

Vascular Dementia Whereas Alzheimer’s disease largely affects nerve cells (gray matter), vascular dementia affects the axons (white matter). In vascular dementia, blood flow to the brain is restricted, resulting in miniscule, undetectable strokes. Accumulated damage results in impaired memory (as well as possible physical debilitation), just like other forms of dementia. Unlike Alzheimer’s disease, vascular dementia can be slowed or prevented by addressing the same risk factors that affect cardiovascular diseases, including physical inactivity, obesity, high serum cholesterol, hypertension, and smoking (Mangialasche, Kivipelto, Solomon, & Frati- glioni, 2012).

Figure 6.8: Brain changes resulting

from Alzheimer’s disease

Alzheimer’s disease causes cells to die and brain tissues to shrink. Consequently, bodily functions deteriorate.

healthy brain

advanced alzheimer’s

mos82599_06_c06_181-218.indd 209 2/11/16 8:26 AM

http://www.alz.org

210

Section 6.6 Stress

6.6 Stress We also know that stress affects the body. For instance, there is convincing evidence that stress is associated with skin diseases, the onset and progression of cardiovascular diseases, the common cold and flu (Assaf, 2013; Ho, Neo, Chua, Cheak, & Mak, 2010; Yan, 2012). But if the environment can cause our bodies to have negative responses, perhaps we can actively promote positive responses as well. The field of psychoneuroimmunology (PNI) explores these connections, studying the relationship between psychological factors like stress (psy- cho-), the brain (-neuro-), and the resulting effects on the immune system (-immunology).

In a pioneering experiment in 1975, a behavioral psychologist and an immunologist joined forces and trained rats to mentally suppress their own immune systems (Ader & Cohen, 1975). Using classical conditioning, the scientists injected the rats with a drug that suppressed their immune systems while they drank a pleasant tasting liquid. Later, the liquid alone was a strong enough stimulus to decrease the immune response in the rats. This research showed that the nervous system and immune functioning were linked. In humans, we have learned that chronic or long-term stress can similarly suppress the immune system by reducing the number of lymphocytes. Consequently, people become more susceptible to disease. Chronic stress can also deregulate immune function and promote autoimmune responses, such as lupus and allergies (Dhabhar, 2009).

Although not completely understood, the pathways that connect the nervous system to the immune system suggest that there is an “integrated network of defenses,” rather than sepa- rated parts (Ader, 2007, p. xvi). If we can partially control the immune system without drugs, then there are important human applications in the areas of transplant surgery and treat- ing autoimmune diseases. Indeed, experimental research has been successful in both sup- pressing and strengthening the immune response in humans in the same way that rats did in earlier studies (e.g., Benedetti, Mayberg, Wager, Stohler, & Zubieta, 2005; Goebel et al., 2002; Schedlowski & Pacheco-López, 2010).

It is generally agreed that exposure to short-term stress, like worrying about a grade or being late, does not have a negative effect on long-term health and mortality. In fact, research indi- cates that it can improve later cellular responses to stress (Epel & Lithgow, 2014). On the other hand, research indicates that prolonged stress promotes aging by increasing cell oxida- tion and shortening the life of cells (Epel, 2009). Several multicultural studies have found that chronic stress promotes the breakdown of multiple body systems, which are in turn associ- ated with disease and early mortality (e.g., McEwen, 2012). We know that various hormones, like cortisol, epinephrine, and even oxytocin, mediate these stress responses, but we are only beginning to understand their roles (Jurek et al., 2015; Ranabir & Reetu, 2011).

Section Review Describe the common illnesses of adulthood. What types of practical measures are available to prevent disability or premature death?

mos82599_06_c06_181-218.indd 210 2/11/16 8:26 AM

211

Section 6.6 Stress

However, instead of stress as a singular cause of negative health outcomes, there is growing evidence that a person’s appraisal of stress is essential to predicting negative health out- comes, not the stress itself. In one study, 28,753 adults reported high levels of stress in a national survey. Researchers then combed through death records in the following eight years to determine mortality rates and associated variables. They found that high levels of stress combined with a perception that stress adversely affects health increased the risk of mortal- ity by 43%. However, a matched group of stressed individuals who did not have the same negative outlook had no increased risk of dying (Keller et al., 2012). While no causal relation- ship has yet been established, the researchers note that the number of deaths each year due to negative appraisals would make stress the 14th leading cause of death in the United States, contributing over 20,000 deaths each year.

It follows that reappraising stressful conditions may lead to health benefits. To study the possible connection, a group of researchers placed 50 partici- pants in a stressful situation. Half were primed to believe that stress is not harmful. Instead, they were informed that the body’s stress response is functional and adaptive. The other half received no instructions and thus served as the control group. Indeed, the reappraisal group had significantly lowered response to the stressful situ- ation, indicating that altering apprais- als is sufficient to change physiological responses to stress (Jamieson, Nock, & Mendes, 2012).

While changing the way we appraise stress may be complicated, other inter- ventions have been shown to be successful in combating stress and improving health. There is well-documented research that exercise and social connections predict health and longev- ity, including serving as a buffer for the negative effects of stress (Holt-Lunstad, Smith, & Lay- ton, 2010). In addition, it appears that helping behaviors specifically promote health and defend against the effects of stress on premature death (Poulin, Brown, Dillard, & Smith, 2013). On the other hand, not only does exercise reduce stress, but the reverse is true as well: when stress is high it often interferes with typical plans for physical activity (Stults- Kolehmainen & Sinha, 2014).

Science Photo Library/Superstock

Worrying about a grade won’t impact your health, but prolonged or chronic stress can lead to disease and early mortality.

Section Review Summarize the research goals of psychoneuroimmunology, and outline the relationship between stress and health.

mos82599_06_c06_181-218.indd 211 2/11/16 8:26 AM

212

Summary & Resources

Chapter Summary As we have learned more about secondary aging factors and preventive efforts in disease, life expectancy has increased dramatically over more than a century. New medicines and technology have allowed us to extend both the quantity and quality of life. Empirical evi- dence about lifestyle factors that help regulate and strengthen body functions continues to accumulate. This information has the potential to contribute to individual gains in longev- ity and quality of life. Making healthy food choices, remaining fit, and avoiding the harmful effects of smoking and drugs promote overall health. The rising epidemic of overweight and obesity contributes to a multitude of problems. On the other hand, in poorer countries, obtaining enough food and avoiding danger is often a daily problem. A number of research and outreach efforts have great potential to improve outlook, but there is considerable work yet to be done.

The two most common causes of death in the United States—cancer and, especially, cardio- vascular disease—are mediated by secondary aging factors, including exposure to the sun and smoke, and diet and exercise. Remaining physically and mentally active also appears to be instrumental in delaying the onset of common degenerative diseases of the brain, but less is known about how to prevent Alzheimer’s disease and Parkinson’s disease. The mind and the body are also joined in the study of psychoneuroimmunology, which informs us of the relationship between stress and overall health. Understanding these connections between psychological well-being, the brain, the mind, and the immune system has the potential to improve people’s functioning by promoting activities that increase health and decrease the prevalence of stress-related illness and early death. Further exploration of the mind and how we think will be the subject of the next chapter.

Summary of Key Concepts Prologue

• Life expectancy in any one region is dependent on both personal and social variables.

• Recent advancements in the collection of data have allowed researchers all over the world to closely investigate rates of disease and mortality.

Nutrition and Activity: Lifestyles and Circumstances

• In wealthy countries, children usually grow up with sufficient quantity of food, but do not always learn good nutritional habits.

• Because of lifestyle changes that appear in young adulthood, adults often gain weight beginning in their 20s and continuing into their 70s.

• Overweight and obesity continue to increase throughout the world and are a par- ticular health concern in the United States.

• To standardize research, overweight is defined as a BMI of 25–29.9 and obesity as a BMI of 30 or more. Because of a continuing trend towards a heavier population, researchers have also begun to refer to grade 2 obesity for a BMI of at least 35 and grade 3 obesity for a BMI of 40 or more.

• About 17% of children are obese and about 35% of adults are obese in the United States.

mos82599_06_c06_181-218.indd 212 2/11/16 8:26 AM

213

Summary & Resources

• Well over 11% of the world’s population is malnourished, which can cause stunting, poor motor skill development, and hamper learning and psychosocial development.

• Marasmus occurs when children’s bodies waste away because they have not con- sumed enough calories. It usually appears during the first year of infancy.

• Kwashiorkor occurs when there is insufficient protein intake. Its common distin- guishing characteristic is a distended stomach. It is usually seen after infancy.

• It is clear that physical activity is essential to optimal health. Despite public appeals to increase physical fitness, few adults satisfy professional recommendations.

Eating Disorders

• Anorexia nervosa is a severe body-image disorder in which individuals refuse to eat because of an obsession with maintaining an unrealistically thin body.

• Bulimia nervosa involves bingeing and purging food several times per day, usually resulting in secondary health complications such as the destruction of tooth enamel.

• The most common eating disorder is binge eating disorder. It is characterized by rapidly eating unusually large amounts of food several times per week, leading to physical discomfort.

• Eating disorders are most common among wealthier, westernized adolescents and young adults.

Illness in Childhood

• Socioeconomic status has a significant effect on health and wellness over the life- span. Due to circumstances beyond personal control, low-SES families tend to have fewer opportunities to maximize health; however, they also tend to make poorer individual choices.

• Asthma is the most common chronic disease of childhood. For unknown reasons, there are significant demographical differences.

• Type 2 diabetes is a major health concern in the Unites States and becoming more of a problem worldwide. The marked increase in cases is due almost exclusively to the rise in overweight and obesity and an overall decrease in physical activity.

Maximizing Childhood Health Outcomes

• Although there have been significant gains since the United Nations established the Millennium Development Goals, decreasing childhood mortality in the poorest coun- tries remains a challenge. Due to wars, disease, and famine, 1 in 10 children do not live past their fifth birthdays in the most vulnerable parts of the world.

• Significant gains have been made in combating poverty, increasing primary school education, addressing disease and mortality due to AIDS and malaria, and providing greater access to clean drinking water.

• The science of disease prevention through the use of immunizations is clear. Despite continuing progress in saving lives throughout the world, there is renewed resis- tance to immunizations among some parents in the United States, resulting in peri- odic outbreaks of disease.

mos82599_06_c06_181-218.indd 213 2/11/16 8:26 AM

214

Summary & Resources

Illness and Disease in Adulthood

• There are more than 25 different types of STDs. Most infections occur among people under 25. STDs caused by bacterial infections are usually easily cured; viruses often have lifelong consequences.

• Whereas the United States has made significant gains, HIV/AIDS continues to be a leading cause of death in many African countries. Antiretroviral agents have been successfully used to treat HIV/AIDS.

• Quitting smoking is usually the single most important action a person can take to preserve health and longevity. It is confirmed that use of tobacco is linked to cardio- vascular disease, a decline in organ functioning, and a host of various cancers. Smok- ing reduces longevity by an average of 10 years.

• Cancer death rates continue to decline in the United States among all racial and ethnic groups. Skin cancer, breast cancer, and prostate cancer are the most common types. Early detection is key to survival.

• Cardiovascular diseases cause heart attack and stroke, which remain the leading cause of death in the United States and around the world. Prevention efforts center on getting enough exercise and eating a healthy diet.

• Chronic obstructive pulmonary disease is largely a result of smoking. When the lungs are prevented from emptying, shortness of breath results.

• Dementia is a general term that refers to diseases that cause an abnormal rate of deterioration of the brain, and therefore mental functioning.

• Parkinson’s disease is the second most common neurodegenerative disease. Initial symptoms include tremors and shaking. A disproportionate number of Parkinson’s patients will develop dementia.

• The majority of dementia cases are due to Alzheimer’s disease. Behaviorally, Alzheimer’s begins like other kinds of dementia. Autopsies reveal two distinguishing features of Alzheimer’s disease: amyloid plaques and neurofibrillary tangles. Though there is little understanding of causes and prevention, the MIND diet appears to be a promising intervention that improves physical and cognitive functioning.

• Unlike Alzheimer’s disease, vascular dementia, thought to be due to micro-strokes that destroy brain tissue, is largely a secondary aging factor, affected by personal choices related to diet and exercise.

Stress

• The field of psychoneuroimmunology explores the relationship between psychologi- cal factors like stress, the brain, and the effect on the immune system.

• Research has demonstrated that we are able to psychologically both increase and decrease our body’s immune response.

• We are only beginning to understand the role of hormones and self-appraisal in the body’s response to stress. There appears to be strong preliminary evidence that stress does not have a one-to-one inverse relationship to health.

Critical Thinking and Discussion Questions

1. Chapters 5 and 6 have discussed primary and secondary aging. Provide examples of both types in your life.

2. Compare the population pyramids for the United States, Western Asia, and South- ern Africa. What accounts for the different shapes? Why are some populations more symmetrical than others?

mos82599_06_c06_181-218.indd 214 2/11/16 8:26 AM

http://populationpyramid.net/united-states-of-america/2015/

http://populationpyramid.net/western-asia/2015/

http://populationpyramid.net/southern-africa/2015/

215

Summary & Resources

3. What do you do in your own life that might increase your life expectancy? What do you do, or have you done, in your own life that might decrease your life expectancy?

4. Use data from the American Human Development Report, provided as a Web Resource in the Additional Resources section, to compare and contrast regional, ethnic, and economic differences in life expectancy. Provide a list of factors that may explain some of the differences.

5. Visit TED (https://www.ted.com/) and watch Kelly McGonigal’s talk, “How to Make Stress Your Friend.” Then investigate ways to change how you appraise stress. What advice can you give others who appear to have a buildup of toxic kinds of stress?

6. You learned about the effects of diets, exercise, and the appraisal of stress in this chapter. Are there any habits you are thinking of promoting in yourself or your fam- ily? If so, explain how you will specifically make those changes. If not, explain why not.

Additional Resources Web Resources

• Measure of America, American Human Development Report: Measure of America 2013–2014 http://www.measureofamerica.org/docs/MOA-III-June-18-FINAL.pdf

• Centers for Disease Control and Prevention: History of vaccine safety http://www.cdc.gov/vaccinesafety/ensuringsafety/history/index.html

• Institute of Health Metrics and Evaluation: Global health research data http://www.healthdata.org/

• The Lancet: Global burden of disease and causes of death visualizations http://www.thelancet.com/lancet/visualisations/cause-of-death

• Let’s Move!: Information to help families make healthy choices and foster physical activity http://www.letsmove.gov/

• The National Institute on Aging’s Go4Life: Information to help older adults make physical activity part of daily life https://go4life.nia.nih.gov/

• UNICEF: Information and statistics about global child nutrition, http://www.unicef.org/nutrition/

• The World Health Organization: Millennium Development Goals http://www.who.int/topics/millennium_development_goals/en/

Key Terms

acquired immune deficiency syndrome (AIDS) A chronic, life-threatening disease that damages the immune system, making a person less able to fight off a variety of ill- nesses and infections. Caused by the human immunodeficiency virus.

Alzheimer’s disease The most common neurodegenerative disease and leading cause of dementia. Characterized by the physical presence of amyloid plaques and neurofibrillary tangles.

amyloid plaques Deposits that clump inside of blood vessels in the brains of people who have Alzheimer’s disease.

mos82599_06_c06_181-218.indd 215 2/11/16 8:26 AM

https://www.ted.com/

http://www.measureofamerica.org/docs/MOA-III-June-18-FINAL.pdf

http://www.cdc.gov/vaccinesafety/ensuringsafety/history/index.html

http://www.healthdata.org/

http://www.thelancet.com/lancet/visualisations/cause-of-death

http://www.letsmove.gov/

https://go4life.nia.nih.gov/

http://www.unicef.org/nutrition/

http://www.who.int/topics/millennium_development_goals/en/

216

Summary & Resources

anorexia nervosa An eating and body image disorder characterized by self-starvation.

arteriosclerosis Hardening of the arteries.

asthma The most common chronic dis- ease in children. Causes breathing airways to become inflamed and narrow, leading to shortness of breath, a feeling of tightness in the chest, and coughing.

binge eating disorder An eating disorder marked by rapidly eating unusually large amounts of food several times per week, leading to physical discomfort.

body mass index (BMI) A number calcu- lated as a ratio of weight to height, which provides a standard to indicate underweight, normal weight, overweight, or obesity.

bulimia nervosa A disorder of weight con- trol characterized by cycles of bingeing and purging.

carcinogens Cancer-causing substances.

cardiovascular disease Diseases related to the heart and blood vessels. Includes arterio- sclerosis and hypertension.

chronic obstructive pulmonary disease (COPD) A lung disease whereby the ineffi- cient exchange of oxygen and carbon dioxide makes breathing difficult.

dementia A broad term that refers to an abnormal rate of deterioration of the brain and mental functioning.

diabetes A chronic disease that occurs when high levels of sugar in the blood are not regulated properly by the body’s systems.

emphysema The most common form of COPD. Usually caused by smoking.

human immunodeficiency virus (HIV) The virus that causes acquired immune deficiency syndrome.

human papillomavirus (HPV) Genital warts; a sexually transmitted infection.

hypertension High blood pressure.

kwashiorkor A consequence of malnutri- tion caused by insufficient protein intake. Characterized by a distended stomach and other swelling.

life expectancy How long a person is expected to live.

malnutrition A condition that results from insufficient intake of nutrients from food.

marasmus A condition of malnutrition that is characterized by wasting.

melanoma The most dangerous type of skin cancer.

neurofibrillary tangles Twisted fibers that build up inside of neurons in the brains of people who have Alzheimer’s disease.

obesity Body weight that is 20% higher than normal for a particular height, defined by a body mass index score of 30 or more. A BMI of at least 35 is referred to as grade 2 obesity, and a BMI of 40 or more is referred to as grade 3 obesity.

overweight Body weight that is operation- ally defined by a body mass index score of 25–29.9.

Parkinson’s disease The second most com- mon neurodegenerative disease. It is caused by the degeneration of neurons that produce dopamine in the brain.

mos82599_06_c06_181-218.indd 216 2/11/16 8:26 AM

217

Summary & Resources

psychoneuroimmunology (PNI) The field of study that explores the relationship between psychological stress, the brain, and the immune system.

sexually transmitted diseases (STDs) The manifestations, or visible signs, of sexually transmitted infections.

sexually transmitted infections (STIs) Refers to having a bacteria or virus that causes a disease, whether or not the dis- ease has manifested. Though there may be no visible signs of a disease, infected indi- viduals can still pass on the pathogen.

vascular dementia Occurs when blood flow to the brain is restricted, damaging white matter and causing loss of function.

mos82599_06_c06_181-218.indd 217 2/11/16 8:26 AM

mos82599_06_c06_181-218.indd 218 2/11/16 8:26 AM