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nutrition_study_guide.pdf
Study Guide
Nutrition
INSTRUCTIONS TO STUDENTS 1
LESSON ASSIGNMENTS 7
LESSON 1: NUTRITION AND THE HUMAN BODY 9
LESSON 2: CARBOHYDRATES, FATS, AND PROTEINS 17
LESSON 3: MICRONUTRIENTS, MINERALS, AND WATER 27
LESSON 4: WEIGHT CONTROL AND NUTRITIONAL NEEDS 35
LESSON 5: LIFE CYCLE, FOOD SAFETY, AND GLOBAL NUTRITION 41
SELF-CHECK ANSWERS 49
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YOUR COURSE Nutrition is the science that investigates how our body takes in, breaks down, and uses foods. The course will provide you with basic information on how these processes take place, including information about nutrients and how they contribute to the way the body functions. This will help you to have a better understanding of your decisions about food and diet. You’ll also learn about physical activities that can contribute to a healthier lifestyle. Because a central focus of nutrition studies is on health promotion, suggestions for individual nutrition choice will be discussed, as well as tactics for maintaining a healthy weight and keeping food supplies safe.
Your course materials have been divided into five lessons. Each lesson is followed by an examination. These lessons are designed to assist you as you read the course textbook, Nutrition for Life, Second Edition, by Janice Thompson and Melinda Manore. This textbook will help you apply nutrition principles to your everyday life. Because nutrition is in a state of constant change, with new technology and new foods introduced to the market daily, your textbook also examines recent changes.
OBJECTIVES When you complete this course, you’ll be able to
■ Evaluate the variety of influences that affect your food choices
■ Utilize a variety of nutrition education materials to increase your knowledge base
■ Identify macro- and micronutrients, their functions, and their effects on health and well-being
■ Discuss basal metabolism, various causes of obesity, and prevention and treatment techniques
■ Identify the components of exercise and the nutritional fuel required to meet your exercise needs
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Instructions to Students2
■ Examine the differences in nutritional needs throughout the life cycle
■ Explain the various factors that affect the safety of food products and the new technologies that affect food supplies
■ Discuss issues involving global food supplies and their relationship to world hunger
KNOW YOUR TEXTBOOK Nutrition for Life focuses on both knowledge and application of the facts of nutrition. Throughout this study guide, you’ll see references to “the textbook” referring you to Nutrition for Life for supportive information. Your examinations for this course will be based upon the textbook readings.
Your textbook sets the stage in the first chapter with advice that will make you more able to prevent nutrition-related dis- eases. The textbook also offers you “Test Yourself” questions (the first one is on page 1 in the textbook) that allow you to evaluate your own knowledge and activity. In each successive chapter, more in-depth information about nutrients, weight management, physical activity, lifestyle, and food safety is presented. The author also provides you with a “Nutri-Case” feature that reflects on the latest nutritional concerns.
Let’s review the textbook and make some suggestions on how it can support your learning when used with this study guide. One of the helpful features of the textbook is the inside back cover, which contains Daily Reference Intake and Recommended Dietary Allowance tables. These allow you to quickly identify your own nutrient needs based on your age, sex, and physiological state (your physical state—for example, whether or not you’re pregnant or breastfeeding). Tolerable Upper Intake Levels (the upper limit of what your body requires) are given for vitamins and minerals as well as daily values (required amounts) for protein, fat, carbohydrate, and vitamin intake.
Instructions to Students 3
There’s a “Brief Contents” listing on page xviii and a detailed “Contents” that can be found on pages xix through xxx (including specific topic areas as well as special features). Special features include “What about You?” which provides some practical ideas on how to improve your eating and “Highlight,” which addresses various nutritional topics. The “Review Questions” at the end of each chapter are also help- ful for reviewing the material you’ve read about. Nutrition- related Web sites are supplied in each chapter, so that you can get to know more about a particular topic by means of the Internet.
Finally, there are excellent and extensive appendices in the textbook beginning on page A-1 and ending on page F-7. The appendices include calculations and conversions, exchanges, charts on caffeine and alcohol, plus stature-for-age informa- tion. The glossary, pages GL-1 through GL-8, plus the index on pages IN-1 through IN-11 will help you define words and terms used throughout the text.
COURSE MATERIALS Your course includes the following materials:
1. Your textbook, Nutrition for Life, Second Edition, by Janice Thompson and Melinda Manore, which contains all your required readings
2. This study guide, which includes an introduction to the course and textbook as well as
■ An explanatory summary of the material you’ll be covering in each lesson
■ A lesson assignment page which lists the schedule of study assignments in your textbook
■ Self-checks with answers that allow you to assess your understanding of the course material
Instructions to Students4
A STUDY PLAN This study guide is intended to help you achieve maximum benefit from this course, by summarizing and clarifying your textbook readings. Your study guide doesn’t replace the text- book but is designed to assist you in understanding the textbook material.
The study guide consists of five lessons. Each lesson con- tains reading assignments, self-checks, and a comprehensive examination on all the material covered. Be sure to complete all work for Lesson 1 before moving to Lesson 2, and so on.
It’s recommended that you keep a learning journal notebook for this course. In this notebook, write down any terms that are unclear. You can check these terms in the glossary at the back of your textbook, beginning on page GL-1, or in a dictionary. In addition, any thoughts or ideas that will help you as you prepare for the examinations can be put in your journal.
To get the most benefit from this course, follow these steps for each of the lessons:
Step 1: Read the introduction to the lesson in this study guide.
Step 2: Read the assigned pages in the textbook. Note where the reading assignment begins and ends and make entries in the journal notebook of terms that require defining.
Step 3: Look in the glossary for the definition of terms and put the definitions in your notebook. Reread all the pages of the assignment, paying special atten- tion to terms that you’ve recorded in the notebook journal.
Step 4: After finishing each reading assignment, complete the self-check. Check your answers with the answers found at the end of this study guide. If your answers were incorrect, review that section of the reading assignment. Remember, the self-checks are only for your use and should not be sent to the school for grading.
Instructions to Students 5
Step 5: When you’re familiar with all the material in the lesson, complete the examination. Take your time doing the examination. When you finish the exam, submit your answers to the school for grading.
Step 6: Repeat these steps for each succeeding lesson until all five lessons are completed and examinations have been sent in to the school.
Remember that at any point in your course you can ask your instructor for information, clarifications, or explanations. E- mail your instructor with your request, and he or she will ensure that you receive an answer. Your instructor’s guid- ance and suggestions should be very helpful as you continue toward completion of this course.
Instructions to Students6
NOTES
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Lesson 1: Nutrition and the Human Body
For Read in the Read in the study guide: textbook:
Assignment 1 Pages 10–13 Pages 1–38
Assignment 2 Pages 14–15 Pages 39–65
Examination 050490 Material in Lesson 1
Lesson 2: Carbohydrates, Fats, and Proteins
For Read in the Read in the study guide: textbook:
Assignment 3 Pages 19–20 Pages 66–97
Assignment 4 Pages 21–23 Pages 98–128
Assignment 5 Pages 24–25 Pages 129–155
Examination 050491 Material in Lesson 2
Lesson 3: Micronutrients, Minerals, and Water
For Read in the Read in the study guide: textbook:
Assignment 6 Pages 28–30 Pages 156–194
Assignment 7 Pages 31–32 Pages 195–230
Assignment 8 Pages 33–34 Pages 231–256
Examination 050492 Material in Lesson 3
Lesson 4: Weight Control and Nutritional Needs
For Read in the Read in the study guide: textbook:
Assignment 9 Pages 36–37 Pages 257–300
Assignment 10 Pages 38–39 Pages 301–332
Examination 050493 Material in Lesson 4
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Lesson Assignments8
Lesson 5: Life Cycle, Food Safety, and Global Nutrition
For Read in the Read in the study guide: textbook:
Assignment 11 Pages 44–46 Pages 333–383
Assignment 12 Pages 47–48 Pages 384–419
Examination 050494 Material in Lesson 5
Note: To access and complete any of the examinations for this study
guide, click on the appropriate Take Exam icon on your “My Courses”
page. You should not have to enter the examination numbers. These
numbers are for reference only if you have reason to contact Student
Services.
Nutrition and the Human Body
INTRODUCTION Your first lesson begins with Assignment 1 and focuses on the first chapter of your textbook, “Nutrition: Making It Work for You.” This chapter gives background information on the “whys” of “what” you eat, and how nutrition contributes to wellness. The first chapter also will help you better under- stand how food choices are based on economics, marketing, and social and cultural considerations.
Assignment 2 covers the second chapter of your textbook, “The Human Body: Are We Really What We Eat?” This chapter discusses the adequacy of the diet you’re presently eating. Beginning with a brief discussion of how the body works, Chapter 2 goes on to explain what makes us human and how our bodies use the food we ingest.
OBJECTIVES When you complete this lesson, you’ll be able to
■ Define the term nutrition and give its history
■ Discuss the various diseases to which inadequate diet may contribute
■ Name the six nutrients and how the body uses them
■ Describe a healthy dies
■ Read food labels
■ Explain why we get hungry
■ List and describe disorders related to specific foods
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ASSIGNMENT 1 Read the following introduction. Then read pages 1–38 in your Nutrition for Life textbook. Remember to log in your notebook journal unfamiliar terms and then look them up in the glos- sary or in a dictionary.
Nutrition is the study of foods (including their nutrients, and chemical components), the actions and interactions of food with the body, and the relationship between food, health, and disease. Sometimes the study of nutrition can be frus- trating, because it deals with science and can be complex. There’s also a problem with misinformation. Much popular information about nutrition is either mistaken or misleading. However, nutrition remains an important area to study because of the large role faulty nutrition plays as a cause of illness and death.
Many factors influence our food choices, including both cog- nitive and affective (emotional) ones. We all “know” that we should eat foods that prevent disease and encourage health, but we’re influenced by advertising, peer pressure, and sim- ple convenience. Cultural and religious influences also have an influence on food choice.
When choosing the foods that you eat, it’s important to con- sider linking nutrients in foods to your health. For this rea- son, there are some general “guiding” principles, such as moderation, variety, and balance. By choosing a variety of foods, you’re less likely to become bored from eating the same foods repeatedly and you get a balance of the nutrients your body needs for good health. Using a moderate approach ensures that your diet will consist of foods that are high in nutrients rather than high in calories, providing the most nutrient contribution with the least amount of calories.
The six classes of nutrients are
■ Carbohydrates (4 calories/gram)
■ Fats (9 calories/gram)
■ Proteins (4 calories/gram)
■ Vitamins (no calories)
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■ Minerals (no calories)
■ Water (no calories)
Carbohydrates, fats, and proteins provide energy, which can be measured in calories (or kilocalories). Proteins and carbo- hydrates each contribute four calories per gram. Fat is the most calorically dense at nine calories per gram, followed by alcohol (not a nutrient, but it does provide calories), which provides seven calories. Multiplying the number of grams by the calorie factor enables you to determine the total number of calories in any food or alcohol product. Vitamins and min- erals help the body regulate calories, but neither provides calories. Water, often forgotten and underrated, is a nutrient that’s greatly needed and is indispensable for bodily activities.
Nutrient recommendations reflect on your body’s need for these six nutrients. The Dietary Reference Intake (DRI), a collaborative effort by the United States and Canada, records current dietary standards and focuses on 14 nutrients. These values are used for planning and evaluating needs through the use of four categories, including Estimated Average Requirement (EAR), Recommended Dietary Allowance (RDA),
Adequate Intake (AI), and Tolerable Upper Intake Levels (UL). all these recommendations are based on scientific research and must be used with the following in mind:
■ They apply to healthy persons only.
■ A large margin of safety is included.
■ The diets contain a variety of foods.
■ Average daily intakes are considered.
■ Each of the four categories serves a unique purpose.
There are many consumer tools for you to use to plan your diet and ensure it’s high in nutrients. The Dietary Guidelines for Americans offers principles of good eating and healthy lifestyle habits and were revised in 2000 to include another tool—the Healthy Eating Pyramid (see Figure 1.11 on page 26 of your textbook).
Lesson 1 11
A key part of consumer nutrition information is the food label, containing specific nutritional facts and health claims, which are regulated by the Nutritional Labeling and Education Act of 1990. The Percentage Daily Values offers a combination of the total fat, saturated fat, and carbohydrate amounts in a food item compared with a person’s estimated daily need of 2,000 calories. Health or nutrient claims must comply with guidelines set by the U.S. Food and Drug Administration (FDA).
Now, read the textbook pages listed in the beginning of this assignment. Then complete Self-Check 1.
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Lesson 1 13
Self-Check 1
At the end of each section of Nutrition, you’ll be asked to pause and check your understanding of what you’ve just read by completing a “Self-Check” exercise. Answering these questions will help you review what you’ve studied so far. Please complete Self-Check 1 now.
1. What are the four top nutritionally related causes of death in the United States?
__________________________________________________________________________
2. Our preferences for food are a _______ response.
__________________________________________________________________________
3. What does DRI stand for?
__________________________________________________________________________
4. Which foods should be chosen sparingly?
__________________________________________________________________________
5. Which of the following is a correct statement about a nutrient-dense food?
a. A nutrient-dense food has all information included on the nutrition label. b. A nutrient-dense food is high in weight and volume. c. A nutrient-dense food provides more nutrients relative to calories. d. A nutrient-dense food contains carbohydrates, proteins, and fats.
6. Which of the following is an alternative for meats in the Food Guide Plan or Pyramid?
a. Bacon c. Baked potatoes b. Nuts d. Cheese
7. The Daily Value on the label is based on the needs for a caloric intake of _______ calories.
a. 1,800 c. 2,200 b. 2,000 d. 3,000
8. True or False? Most ethnic foods don’t fit into a food guide pyramid and should be avoided.
Check your answers with those on page 49.
ASSIGNMENT 2 Read the following introduction. Then read pages 39–65 in your Nutrition for Life textbook. Remember to log in your notebook journal any unfamiliar terms and then look them up in the glossary or in a dictionary.
Assignment 2 provides a mini biology lesson that explains what happens to the human body when we eat. It begins with an explanation of the microscopic parts of the body, the atoms that form molecules, the molecules that form cells, and the cells that form tissues and organs. The chapter goes on to explain the physiological foundations of hunger, and then explains just what happens to food on its path to and from the organs and bloodstream.
When we eat, we turn food into energy. For us to do that, our bodies need to chemically break that food down into sub- stances that can be absorbed. This chemical breakdown is accomplished through the production of enzymes and other digestive juices produced in the different organs of the body.
As you read the material in Chapter 2, pay particular attention to the terminology highlighted in the margins. Many of these terms will be used again in later chapters.
As you conclude this lesson, explore the Web sites listed in Chapters 1 and 2 of your textbook. These sites are great sources of worthwhile information. Take the time to visit some of these Web sites, and bookmark the more informative ones.
Now, read the textbook pages listed in the beginning of this assignment. Then complete Self-Check 2.
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Lesson 1 15
Self-Check 2
Indicate whether the following statements are True or False.
_____ 1. The smallest units of matter are the molecules.
_____ 2. We can control the hypothalamus to tell us to be hungry.
_____ 3. Protein makes us feel full for a longer period of time than carbohydrates do.
_____ 4. Chewing chemically breaks down food.
_____ 5. The gall bladder stores the bile produced by the liver.
_____ 6. When blood travels through the body it picks up waste products.
Check your answers with those on page 49.
NOTES
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Carbohydrates, Fats, and Proteins
INTRODUCTION Your second lesson covers Chapters 3, 4, and 5, in your text- book, Nutrition for Life. Chapter 3 deals with the various types of carbohydrates in the diet, detailing the simple carbohy- drates, the monosaccharides (a single sugar), the disaccha- rides (pairs of sugars or double sugars), and polysaccharides (complex carbohydrates such as starch and fiber). Many of the foods on the MyPyramid contain carbohydrates. A large section of Chapter 3 is devoted to the complex carbohydrate fiber, primarily due to fiber’s many health benefits.
Assignment 4 covers Chapter 4 in your textbook, “Fats: Essential Energy-Supplying Nutrients.” In Chapter 4, two types of lipids are discussed, triglycerides and cholesterol. Both of the lipids are “built” from fatty acid chains and con- tain, in the polyunsaturated group, the extremely important essential fatty acids. Remember that essential means the nutrient is essential to life and must be provided by what you eat. Your body can’t make or synthesize essential fatty acids all by itself. Next, the chapter discusses cholesterol, and explores the relationship between cholesterol and heart disease. Other suggestions for controlling cholesterol are given, as well as suggestions for general lipid reduction.
Finally, this lesson will conclude with a survey of Chapter 5, “Proteins: Crucial Components of All Body Tissues.” Many proteins are considered essential. (Your body needs them, but can get them only from what you eat.)
The “building blocks” of proteins, the amino acids, allow proteins to have more functions than any other nutrient. The chapter closes with a discussion of protein-deficiency diseases and a look at the special needs for proteins in vegetarian diets.
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OBJECTIVES When you complete this lesson, you’ll be able to
■ Explain the categories included in carbohydrate metabolism
■ Discuss the relationship between sugar and health, especially dental health
■ Explain the sources and function of fiber in the diet
■ Name the variety and properties of artificial sweeteners available today in the marketplace
■ Explain the functions of lipids, such as glycerols and sterols
■ Name and discuss the health function of the essential fatty acids
■ Explain the differences between the following kinds of fatty acid: monounsaturated, polyunsaturated, unsatu- rated, and saturated
■ Describe the controversy about cis and trans fatty acid
■ Define the term cholesterol
■ Discuss the role of fat and cholesterol in the diet and its effect on a person’s health, especially cardiovascular health
■ Explain what an amino acid is
■ Discuss the many functions that proteins have
■ Tell which diseases result from inadequate protein intake
■ Explain the special dietary needs of vegetarians
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Lesson 2
ASSIGNMENT 3 Read the following introduction. Then read pages 66–97 in your Nutrition for Life textbook. Remember to log in your notebook journal any unfamiliar terms and then look them up in the glossary or in a dictionary.
Carbohydrates play a crucial role in the body’s metabolism (breaking down and using new materials for bodily function- ings). One result of carbohydrate intake is the production of sugars, such as the monosaccharides (fructose, galactose, and glucose) and the disaccharides (sucrose, maltose, and lactose). Other important carbohydrates are called complex. They’re the polysaccharides (starch, glycogen, and fiber).
Over 55% of our dietary intake consists of carbohydrates, a nutrient group whose main function is to provide energy sources for the body. Glycogen is a stored form of glucose, found in the muscle and in the liver. It’s estimated that peo- ple store over 1,500 calories of glycogen in their bodies as a reserve source of energy.
The complex carbohydrates, starch and fiber, have been linked to a reduced risk of excess weight gain, lesser gastrointestinal disorders (disorders involving either the stomach or the large and small intestine), decrease of some forms of cancer and better control of high blood glucose levels found in those who suffer from diabetes.
Now, read the textbook pages listed in the beginning of this assignment. Then complete Self-Check 3.
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Self-Check 3
1. Sucrose bonds together fructose and
a. glucose. c. salactose. b. galactose. d. maltose.
2. Another word for milk sugar is
a. lactase c. maltose b. sucrose d. amylase
3. According to the DRI, the number of calories from carbohydrates should be approximately _______.
4. Frequent urination, extreme hunger, and fatigue are symptoms of _______.
5. Blood concentrations of glucose that are too low are called _______.
Check your answers with those on page 49.
ASSIGNMENT 4 Read the following introduction. Then read pages 98–128 in your Nutrition for Life textbook. Remember to log in your journal notebook unfamiliar terms and then look them up in the glossary or in a dictionary.
Lipids are nutrients, and can be broken into three subdivi- sions—triglycerides, cholesterol, and phospholipids. Lipids are made of fatty acids. Fatty acids may be long-, medium-, or short-chained; and either saturated (having a maximum number of hydrogen atoms), monounsaturated (containing one point where additional hydrogen atoms can be added), or polyunsaturated (containing two or more points where addi- tional hydrogen atoms can be added). The polyunsaturated fat category contains the omega-3 (linolenic) and omega-6 (linoleic) fatty acids, which are essential (they must be pro- vided for by diet—the body can’t synthesize them all by itself).
The largest category by far is the triglycerides, making up about 95% of daily fat intake. They’re fats and oils composed of fatty acids and glycerol, which serves as a structural sup- port for triglycerides. Triglycerides provide energy insulation and protect internal organs from shock. They help the body effectively use carbohydrates, proteins, and the fat-soluble vitamins A, D, E, and K. Triglycerides add satiety (the feeling of being satisfied) to the diet and deliver flavor, texture, and tenderness to food.
Cholesterol is found only in animals and animal products. So any foods you eat from animal products, such as eggs, fish, or cheese, contain cholesterol. Even the fat in the “low-fat” or “lean” products is cholesterol. Most of our cholesterol is pro- duced by the liver. It’s used to synthesize bile, sex hormones, and Vitamin D, among other functions.
Phospholipids are used as emulsifiers (water and fat mixtures) in foods and in the body, and are part of the structure of lipoproteins. Bile is an emulsifier, secreted into the small intestine, which assists with digestion. Both of these are needed in moderate amounts and are produced by the body as needed.
Lesson 2 21
The current recommendation for your dietary intake is a maximum of 30% of calories from fat, with 10% or less being saturated and at least 10% being monounsaturated. Your cholesterol intake shouldn’t exceed 300 mg per day. A blood test called a fasting lipid profile is important to monitor these lipids and reduce your risk of heart disease. Excess lipids also contribute to obesity, some cancers, diabetes, and hypertension (high blood pressure).
Now, read the textbook pages listed in the beginning of this assignment. Then complete Self-Check 4.
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Lesson 2 23
Self-Check 4
Indicate whether the following statements are True or False.
_____ 1. Cholesterol is an essential fatty acid and must be supplied by the body.
_____ 2. A polyunsaturated fatty acid has two or more double bonds.
_____ 3. Saturated fat should be kept low and contribute less than 10 percent of calories.
_____ 4. Linoleic acid is not an essential fatty acid.
_____ 5. High-density lipoproteins are sometimes referred to as the “good” cholesterol.
Check your answers with those on page 50.
ASSIGNMENT 5 Read the following introduction. Then read pages 129–155 in your Nutrition for Life textbook. Remember to log any unclear terms in your notebook journal, and then look them up in the glossary or in a dictionary.
Protein is composed of amino acids, and they can perform many more functions than fats or carbohydrates. Twenty different amino acids form proteins, and about half of them are essential, meaning that they’re vital for health and must be obtained from the diet.
Proteins have many functions. They assist in the growth and repair of tissue and cells. Enzymes, hormones, and antibod- ies rely upon protein. Proteins help with fluid and acid-base balance and aid in transporting nutrients, helping blood to clot, and maintaining vision.
Food proteins may be either complete (proteins that have all the essential amino acids) and have a high biological value, or incomplete (proteins that lack or have low amounts of essential amino acids). Incomplete proteins need to be sup- plemented to provide high nutritional value.
It’s recommended that 10–15% of your dietary intake come from protein. Most of us eat far more than that each day, so protein supplementation is usually unnecessary and can be dangerous.
People who are chronically ill can have protein deficiencies that cause decubitus (erosion of the skin that comes from the inside out, commonly called bed sores). Even more serious, a devastating form of protein deficiency (a kind of malnutrition) results in diseases called marasmus and kwashiorkor, which are common in children and the elderly in developing nations.
As you conclude this lesson, explore the Web sites mentioned in Chapters 3, 4, and 5 in your textbook Nutrition for Life.
Now, read the textbook pages listed in the beginning of this assignment. Then complete Self-Check 5.
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Self-Check 5
1. True or False? Peptide bonds bind amino acids together chemically.
2. True or False? There are no known benefits from consuming excess protein.
3. The building blocks of protein are _______.
4. Cancer-causing agents are called _______.
5. The adult RDA for protein is _______ per kilogram of body weight.
Check your answers with those on page 50.
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Micronutrients, Minerals, and Water
INTRODUCTION This lesson covers Chapters 6, 7, and 8 in your Nutrition for Life textbook. In assignment 6, you’ll consider vitamins, subdivided into two categories, water-soluble (vitamin C and B-complex) and the fat-soluble (vitamins A, D, E, K). Food sources for vitamins are given and vitamin deficiencies are discussed.
In assignment 7 you’ll consider minerals, and in assignment 8 you’ll explore how the body uses water.
OBJECTIVES When you complete this lesson, you’ll be able to
■ Name the water-soluble and the fat-soluble vitamins
■ Discuss the role antioxidants play in health and aging
■ Explain the function of the various vitamins in the body system
■ Describe the diseases that can occur when someone doesn’t get enough of a particular vitamin
■ State food sources for water-soluble and fat-soluble vitamins
■ Discuss cooking and storage methods to best preserve vitamins
■ Explain what phytochemicals are and how they promote health and reduce disease risks
■ Discuss the various functions of water in the body system
■ Identify the major and trace minerals and their function in the body
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■ Compare and contrast the health benefits and health risks of alcohol intake
■ List the food sources of major and trace minerals, and the diseases that result from low mineral levels
■ Compare and contrast the roles of various electrolytes
■ Discuss the role of minerals in the control of hyper- tension
■ Describe the symptoms and the treatment of osteoporosis
ASSIGNMENT 6 Read the following introduction. Then read pages 156–194 in your Nutrition for Life textbook. Remember to log unclear terms in your journal notebook and then look them up in the glossary or in a dictionary.
Vitamins function differently from the energy-yielding nutri- ents we’ve just studied. They don’t yield energy but they do help the body to release energy from food. Vitamins are essential in supporting life and health, and all have unique characteristics. In your textbook, Nutrition for Life, the chapter on vitamins contains Tables 6-1 and 6-2 on pages 159–160, which list information about water-soluble and fat-soluble vitamins.
Water-soluble vitamins can’t be stored by the body and are required in frequent small amounts. They’re excreted daily in urine if there’s any excess, so the water-soluble vitamins need to be replaced on a daily basis. These vitamins tend to be safe unless taken in massive amounts. Vitamin C has been identified as an antioxidant (a substance that prevents damage to your body because of chemical reactions using oxygen). Folic acid has been found to be helpful in prevent- ing certain birth defects.
The fat-soluble vitamins A, D, E, and K, have very specific functions. Vitamin A is important for vision, for healthy epithelial (outer surface) cells, and for immunity and bone growth. One plant form of vitamin A is beta-carotene, another recognized antioxidant. Vitamin D works with sunlight to perform bone formation and maintenance. Vitamin E is also
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Lesson 3
an antioxidant found in vegetable oils, while vitamin K aids in blood clotting. The fat-soluble vitamins are housed in fatty tissue because they’re fat-soluble. They can be toxic to the body if taken in excess, because the body doesn’t easily excrete them.
Now, read the textbook pages listed in the beginning of this assignment. Then complete Self-Check 6.
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Self-Check 6
1. True or False? In foods, the water-soluble vitamins are stored in the body.
2. True or False? Antioxidants help the body to remove free radicals.
3. True or False? Beta-carotene is the precursor to Vitamin D.
4. The deficiency disease of vitamin C is _______.
5. The vitamin that can be formulated through exposure to sunlight is _______.
Questions 7–10: Read the scenarios below. In each case, indicate which vitamin the person may be lacking.
6. Grandpa doesn’t like milk, cheese, or vegetables. Lately, he’s noticed that he doesn’t feel comfortable driving at night. It’s hard for him to see the road after a passing car’s headlights shine in his eyes.
__________________________________________________________________________
7. Aunt Jillian says the sun bothers her eyes, and as a result, she rarely goes out during the day. Her diet tends to consist of herbal tea, fruit, rice, and salad.
__________________________________________________________________________
8. Whenever George gets a cold, it seems to last forever. He’s generally under a lot of stress and tends to drink coffee rather than juice.
__________________________________________________________________________
9. Uncle Timo is a vegan. He says that he’s been feeling tired lately and that his muscles ache.
__________________________________________________________________________
Check your answers with those on page 50.
Lesson 3 31
ASSIGNMENT 7 Read the following introduction. Then read pages 195–230 in your Nutrition for Life textbook. Remember to log unclear terms in your journal notebook and then look them up in the glossary or in a dictionary.
This chapter discusses those minerals that are of greatest importance in human nutrition. Calcium is the most abun- dant mineral in the body and is stored mainly in the bone structure. It functions in blood clotting, nerve and muscle function, and in cell metabolism. Calcium is found in milk and dairy products, and deficiencies lead to rickets (a bone disease caused by lack of vitamin D and sunlight) in chil- dren or osteoporosis (a disease in which bones weaken and become brittle) in adults.
Phosphorus, another major mineral, is widespread in foods and rarely is deficient in the diet. Its primary function is to work with calcium in formation of bone crystals and it’s part of DNA, RNA, and the previously studied phospholipids and lipoproteins.
The trace minerals are found in your body in smaller amounts and are involved in a variety of structural and regulatory func- tions in the body. Iron is one trace mineral that’s of paramount importance. It’s found in meat, vegetables, nuts, beans, and iron-enriched foods. Zinc, required for normal growth develop- ment and immune function, is also found in plant foods and meat. Selenium, which acts an antioxidant, and iodine, impor- tant for thyroid functioning, are well-researched minerals.
Now, read the textbook pages listed in the beginning of this assignment. Then complete Self-Check 7.
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Self-Check 7
1. True or False? Drinking water is the usual source of fluoride.
2. The most abundant mineral in the body is _______.
3. The trace mineral whose deficiency will lead to anemia over time is _______.
4. The trace mineral whose deficiency will lead to thyroid malfunction is _______.
5. If _______ isn’t replenished daily, poor appetite, delayed healing, increased colds and flu, or night blindness may occur.
Check your answers with those on page 51.
ASSIGNMENT 8 Read the following introduction. Then read pages 231–256 in your Nutrition for Life textbook. Remember to log unclear terms in your journal notebook and then look them up in the glossary or in a dictionary.
Chapter 8 covers the subject of alcohol and nutrition. In this chapter, you’ll cover information on factors affecting the absorption and metabolism of alcohol, including gender, ethnicity, and diet makeup.
Water is considered by many to be one of the most important nutrients. We can live a lot longer without food than we can without water. Unfortunately, water is often looked upon as the “last choice” among thirst-quenchers. Juices, soda, and sports beverages often replace water. As a country, many Americans don’t meet their nutritional need of 1 quart of water per 1,000 calories of food. Many beverages that con- tain caffeine or alcohol are natural dehydrators, meaning that they actually increase the body’s need for water. One of the other problems is thirst; the brain doesn’t activate your need for water until you’re already dehydrated by 2%. Needs for water increase when the weather is hot and humid, so sports enthusiasts especially need to learn to “drink on a schedule” rather than risk dehydration. In addition, if you weigh yourself before a sports event, and immediately after- ward, you can determine fluid losses. It takes 16 ounces of water to replace a pound of weight lost through dehydration.
Water has a multitude of functions in the body, including carrying other nutrients and waste through the body. It par- ticipates in chemical reactions, helps form macromolecules and regulates body temperature. Water acts as a lubricant for joints and shock absorber for your organs. As a solvent, it helps maintain your acid-base pH balance. Electrolytes (ions dissolved in water—sodium, potassium, and chloride) help keep your body water in equilibrium (normal fluid balance).
Now, read the textbook pages listed in the beginning of this assignment. Then complete Self-Check 8.
Lesson 3 33
Nutrition34
Self-Check 8
Indicate whether the following statements are True or False.
_____ 1. Interstitial fluid is external to tissue cells.
_____ 2. Orange juice hydrates the body better than water does.
_____ 3. It’s impossible to drink too much water.
_____ 4. Alcohol is digested in the liver.
_____ 5. To break down alcohol more quickly, one should drink coffee.
Check your answers with those on page 51.
Weight Control and Nutritional Needs
INTRODUCTION In Lesson 4, you’ll be concentrating on two chapters of your textbook, Chapter 9 “Achieving and Maintaining a Healthful Body Weight” on pages 257–300 and Chapter 10 “Nutrition and Physical Activity: Keys to Good Health,” on pages 301–332. Both of these chapters deal with a healthy weight and how to achieve and maintain it. Achieving a healthy body weight is important for avoiding a high incidence of health problems. Obese (or greatly overweight) people have a higher incidence of disease and death from their health problems.
OBJECTIVES When you complete this lesson, you’ll be able to
■ Discuss the health risks of being overweight or obese
■ Describe the various techniques to assess body weight and body fat
■ Identify the causes of obesity, both the genetic and environmental
■ Explain some successful techniques for weight loss and maintenance
■ Identify the reason why exercise must become part of everyone’s lifestyle
■ Discuss the four fitness components and how each affects our health profile
■ Explain anaerobic and aerobic exercise and the functions of each
■ Identify the nutritional needs during exercise for foods and for fluids
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ASSIGNMENT 9 Read the following introduction. Then read pages 257–300 in your Nutrition for Life textbook. Be sure to log any unclear terms in your journal notebook and then look them up in the glossary or in a dictionary.
Energy requirements are determined from basal (essential and fundamental) metabolic needs and activity levels. These energy requirements, called caloric need, are determined by what your body uses daily for all these activities. If an excess number of calories are consumed, a person gains weight. If there’s a decrease in calorie consumption, a person loses weight.
Treatments available range from surgery to pharmacological treatment to support groups using a behavioral approach. Gimmicks and “quick fixes” abound, with consumers spending about $33 billion dollars last year on a variety of products, treatment, and programs. Only five percent of the people in the United States maintain weight loss after 3–5 years. Successful techniques like behavior change, positive attitude, and main- tenance groups for continued support of weight loss seem to work best.
No matter how controversial the measurement or the treat- ment, one fact remains critical—being overweight or under- weight poses a health problem. There’s a strong causal rela- tionship between obesity and cardiovascular disease, diabetes, and cancer. Likewise, a fixation with being underweight can lead to eating disorders like anorexia nervosa (depriving one- self of adequate amounts of food) and bulimia (forcing oneself to vomit or excrete food that’s been eaten).
Now, read the textbook pages listed in the beginning of this assignment. Then complete Self-Check 9.
Nutrition36
Lesson 4 37
Self-Check 9
1. A person classified as overweight has a body mass index of
a. 18.5. c. 25.1–29.9. b. 18.5–25. d. 30 or higher.
2. The body’s first adjustment to fasting is to
a. stop functioning. c. break down bile. b. reduce carbohydrate intake. d. use the liver’s glycogen.
3. About 60 percent or more of the energy the average person spends goes to support the ongoing metabolic work of the body’s cells or the _______.
Questions 4–6: Indicate whether the following statements are True or False.
_____ 4. There are few health risks associated with obesity.
_____ 5. Someone who has a weight 50% above the weight standard for height or weight is determined to be morbidly obese.
_____ 6. Bioelectrical impedance can measure body fat because water is a good conductor of electricity.
Check your answers with those on page 51.
ASSIGNMENT 10 Read the following introduction. Then read pages 301–332 in your textbook Nutrition for Life. Be sure to jot down any unclear terms in your journal notebook and then look them up in the glossary or in a dictionary.
Exercise, or regular physical activity, promotes health, reduces the risk of chronic disease, and is beneficial to you—physical- ly, psychologically, and often socially. As you become more committed to physical activity, you’ll achieve fitness, a state where you can meet life’s demands with energy to spare! The components of fitness include
■ Flexibility
■ Strength
■ Muscle endurance
■ Cardiorespiratory endurance
Improving your fitness involves a schedule of exercise. Muscles respond to demands of work capacity and increase in size, while cardiovascular conditioning improves your heart and lung function to bring more oxygen to your cells. Therefore strength, anaerobic (using resistance training and muscle endurance), and aerobic (using oxygen through the cardiorespiratory [heart and lung] system) activities need to be included in a balanced fitness program.
As with most changes in lifestyle, a new mixture of “food fuels” is needed for this increase in physical activity. Carbohydrates, especially those that are complex and high in fiber, are the major source of energy for fitness. Protein needs are slightly higher than those of a person who doesn’t exercise, but don’t “overload” on proteins with supplements and high-protein diets. Too high a level of protein can be dangerous. Fat consump- tion is helpful, but shouldn’t exceed 30% of the caloric intake. Water is the most essential nutrient during training and com- petition and needs to be replaced, especially if fluid losses are high because of heat. Superior performance often depends on adequate fluid intake! As you conclude this lesson, explore the Web sites mentioned in Chapters 9 and 10 of your textbook.
Now, read the textbook pages listed in the beginning of this assignment. Then complete Self-Check 10.
Nutrition38
Lesson 4 39
Self-Check 10
1. True or False? Creatine is found in fish and is stored in our muscles.
2. Determine the maximum heart rate (MHR) for a person who is 30 years old.
a. 110 c. 130 b. 114 d. 190
3. True or False? Muscle endurance is a muscle’s power to continue working for long periods.
4. True or False? One the effects of cardiovascular conditioning is an increase in total blood volume.
5. Hormones that are sometimes abused by athletes and may be dangerous to physical and mental health are _______.
Check your answers with those on page 51.
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NOTES
Life Cycle, Food Safety, and Global Nutrition
INTRODUCTION This final lesson covers the last two chapters of your textbook— Chapter 11, which takes you through the nutritional needs throughout the life cycle, and Chapter 12, which deals with food safety and the global food supply.
Good nutritional and lifestyle habits should begin when a woman is planning a pregnancy. Folic acid is recommended to prevent neural tube defects. Substance abuse, use of tobacco, alcohol, drugs, and even herbs should be discontinued before the onset of pregnancy to avoid complications.
Adequate nutrient and caloric intake is important for the normal growth of the fetus and the health of the mother. Caloric increase becomes more important in the second and third trimesters of pregnancy, and there’s also an increased need for protein, B-complex vitamins, vitamin D, iron, and zinc. These needs can be met by a balanced diet, with extra nutrient-dense foods and prenatal vitamin supplementation.
Many health problems can occur during pregnancy, including nausea and diarrhea, and they need to be carefully monitored. High-risk pregnancies can involve the mother’s age, socioeco- nomic status, poor nutrition, or history of substance abuse. Lactation (the production of breast milk) is a physiological state that requires additional nutrients, vitamins, minerals, and water in the mother’s diet.
An infant’s rapid weight gain during the first year of life requires an ample supply of all the nutrients. Breast milk provides the nutrients needed for the first 4–6 months, as does an iron-fortified formula. Additions to the baby’s diet should be gradually made. By the age of one, foods from all the food groups should be included in the diet. The first year of life is most important for setting a child’s positive eating habits. As the child grows, he or she needs to be provided with healthful food choices and regular physical activity to
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promote growth and help prevent diseases from occurring later in life. It’s important that children have balanced meals that provide adequate nutrients.
Nutrient and energy needs rise rapidly during adolescence. Because teens begin to make their own choices and food selections, nutritional deficiencies can occur quickly, espe- cially those that involve iron and calcium. Busy lifestyles, peer pressure, and irregular eating habits add to the chal- lenge of wide food choices by adolescents.
There are also special health and nutrition issues for older adults. Both health and increased life expectancy in the United States have increased dramatically, due in part to good nutrition and increased physical activity. However, there are particular problems that older adults face. The aging of body cells can contribute to reduced digestive func- tion, changes in blood levels, and other functional changes in organs such as the heart, liver, kidney, and brain. Keeping to a good regime of physical activity can slow this process. The following also help:
■ Adequate nutritional intake
■ Proper calorie levels
■ Moderate to low fat intake
■ Adequate protein intake
■ Including complex carbohydrates that are high in fiber
■ Maintaining adequate levels of water and other fluids
Vitamins and minerals of particular importance are
■ Vitamin A
■ Vitamin D
■ Vitamins B6 and B12
■ Zinc
■ Iron
■ Calcium
Nutrition42
Psychological factors like loneliness, depression, and lack of money also deserve consideration.
Illnesses caused by food are extremely common. Numerous factors contribute to the problem, including poor handling, processing, packaging, and preparation of foods.
Here are some tips:
■ Avoid cross-contamination (using the same work surface for both raw and prepared foods).
■ Cook at high enough temperatures to kill microorganisms.
■ Use hot, soapy water for washing your hands and your utensils.
Pesticides are often used to protect foods against insects, but the amounts utilized are carefully monitored by the EPA (Environment Protection Agency) and the FDA (Food and Drug Administration). Food additives, including artificial col- ors, flavors, and nutrient additives, are also monitored.
Chapter 12 contains a discussion of poverty and hunger in the United States and in the world. Government assistance programs aren’t the only solution. Personal action to reduce, reuse, recycle, and cut back use of energy is needed as well.
OBJECTIVES When you this lesson, you’ll be able to
■ Explain the nutritional needs of women during pregnancy and lactation
■ Discuss the nutritional needs of a young child
■ Explain the factors that affect children’s eating habits
■ Compare the nutritional needs of adolescents to their actual consumption patterns
■ Discuss the nutrition-related problems of adolescents
■ Identify the nutritional needs and problems of the aging population
Lesson 5 43
■ Explain the causes of foodborne illness
■ List foodborne microorganisms and the diseases that they can cause
■ Describe storage and preparation procedures for increas- ing food safety
■ Identify pesticides and other chemical contaminants that can affect food
■ Summarize the most common food additives and their major uses
■ Discuss undernutrition and its effect on both domestic and global societies
ASSIGNMENT 11 Read the following introduction. Then read pages 333–383 in your textbook Nutrition for Life. Write in your journal note- book any unfamiliar terms and then look them up in the glos- sary or in a dictionary.
The physiological state that makes the greatest nutritional demand on a woman’s body is pregnancy. Caloric needs dur- ing pregnancy increase by about 300 calories per day for the last six months of pregnancy. A woman’s preparation for these needs should occur even before pregnancy begins. Research shows that the physical and intellectual develop- ment of the fetus is greatly stimulated when nutritional needs are met during those early months of life. Women with high-risk pregnancies should also be careful to supplement their ordinary diets. Factors that contribute to high-risk pregnancies are
■ Young age of mother
■ Having had several pregnancies with little time between successive pregnancies
■ Drug use
■ Alcohol use
■ Cigarette smoking
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Breastfeeding is the most natural way to feed a newborn infant and provides both great nourishment and important protective antibodies. Although the ideal is to breast-feed for at least six months to a year, even a few weeks or months of breastfeeding will help the infant to develop stronger immu- nity to disease.
Adolescence is a time of great hormonal and emotional changes. Moreover, young teens become more subject to peer pressures. This is a stage where kids often skip meals and base their food decisions on what their friends are eating. Some problems kids encounter in adolescence are
■ Obesity
■ Calcium deficiencies
■ Iron deficiencies
■ Eating disorders
Now, read the textbook pages listed in the beginning of this assignment. Then complete Self-Check 11.
Lesson 5 45
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Self-Check 11
1. As one ages, absorption of _______ increases.
a. zinc c. vitamin D b. vitamin C d. vitamin A
2. True or False? Heredity is a factor you can’t control, but nutrition is a factor that you can control.
3. True or False? Seeds or beans are part of the meat or meat alternate group in the MyPyramid for Kids.
4. If a woman is at normal body weight, an average weight gain in pregnancy is _______ pounds.
5. True or False? Only 25% of all pregnant women experience morning sickness.
6. True or False? Hormones, stress, genetics, and hygiene contribute to adolescent acne.
Check your answers with those on page 52.
ASSIGNMENT 12 Read the following introduction. Then read pages 384–419 in your Nutrition for Life textbook. Remember to record unclear terms in your journal notebook and then look them up in the glossary or in a dictionary.
Foodborne illness cases are on the rise in this country, including reported cases of food poisoning. Cases of nausea, diarrhea, and stomach cramping are often written off as a gastrointestinal flu, when they may have actually been caused by consumption of a tainted or mishandled food product! Microbial agents are considered the most dangerous, especially in certain segments of our society. Small children or the elderly population dehydrate much more quickly, have lower natural immune resistance, and can become very ill from even limited exposure. Microorganisms thrive at certain temperatures, and yet it’s still common to see foods left out to cool before refrigerating.
Thinking about how your foods are handled will prevent need- less exposure to the microbial food agents listed in Table 12.1 on pages 386–387 of your textbook. Safe food storage and preparation is the key to keep you, your family, and your guests well!
Possible exposures to pesticides and other chemical contami- nants range from the residual effect of contaminants that are in the air to the use of your grandmother’s lead crystal pitch- er. As we have more changes in air quality due to pollutants and more degrading of the ozone layer in the atmosphere, this will become more of a danger to our food supply and its safety.
Many persons who are concerned with the foods they’re eat- ing are joining organic “co-ops,” where organically grown fruits and vegetables are purchased weekly during their growing season. At a much lower price than the supermarket “organics,” there’s comfort in knowing you’re preparing “fresh” fruits and vegetables untainted by pesticides or such things as “wax coating” to improve sales. If interested, check with your local Department of Agriculture for the closest organic food cooperatives.
Lesson 5 47
Food additives are well regulated by the FDA and must follow the guidelines of the GRAS (Generally Recognized as Safe) listing. Besides extending use time for consumption, they protect food quality and color through preservation. Remember to check expiration dates when you’re in the supermarket. Often, an outdated product is purchased by a shopper who forgets to check the date.
As you conclude this lesson, explore the Web sites mentioned in Chapters 11 and 12 of your textbook Nutrition for Life. Now, read the textbook pages listed in the beginning of this assignment. Then complete Self-Check 12.
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Self-Check 12
1. The process of using energy to destroy microorganisms in foods is called
a. irradiation. c. transmutation. b. biotechnology. d. organic food production.
2. True or False? Honey can be a cause of botulism for infants and small children.
3. True or False? Substances that are placed in foods deliberately are called direct or intentional food additives.
4. A heavy metal that contaminates seafood near industrial coasts is _______.
5. The substances used to prevent, destroy, or repel harmful pests are called _______.
Check your answers with those on page 52.
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Self-Check 1
1. Heart disease, cancer, stroke, and type 2 diabetes
2. learned
3. Dietary Reference Intake
4. Red meat, butter, white rice and bread, potatoes, pasta, and sweets
5. c
6. b
7. b
8. False
Self-Check 2
1. False
2. False
3. True
4. False
5. True
6. True
Self-Check 3
1. a
2. a
3. 45–65 percent of daily calories
4. type 1 diabetes
5. hypoglycemia
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Self-Check 4
1. False
2. False
3. True
4. False
5. True
Self-Check 5
1. True
2. True
3. amino acids
4. carcinogens
5. 0.8 grams
Self-Check 6
1. False
2. True
3. False
4. scurvy
5. vitamin D
6. Vitamin A
7. Vitamin D
8. Vitamin C
9. Vitamin B12
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Self-Check 7
1. True
2. calcium
3. iron
4. iodine
5. zinc
Self-Check 8
1. True
2. False
3. False
4. False
5. False
Self-Check 9
1. c
2. c
3. basal metabolism
4. False
5. False
6. True
Self-Check 10
1. True
2. d
3. True
4. True
5. steroids
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Self-Check 11
1. d
2. True
3. True
4. 25–35
5. False
6. True
Self-Check 12
1. a
2. True
3. True
4. mercury
5. pesticides
