Nutrition Hmw One Forum and One DIET ANALYSIS ASSIGNMENT
MINERALS
classification
Major minerals
- needed in the body in the largest amounts
requirements >100 mg/day
calcium, sodium, potassium, phosphorus
- There are many more minerals and trace elements, however, we will be focusing on the ones that are the most problematic in human nutrition and those which are important for chronic disease prevention.
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Calcium
Main functions:
- bone/tooth formation
- regulation of nerve transmission, blood clotting, contraction of muscles
- helps maintain normal blood pressure
Stored in:
- 99% of the total calcium in the body is stored in the bones
- 1% of the total calcium in the body is found in the blood
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- Calcium stored in the bones serves as a reservoir of calcium. Its there to help maintain blood calcium levels when intake of calcium is low.
- A chronically poor intake of calcium, over a number of years, causes a lot of calcium to removed from the bones to supply the blood (which is used for more immediate needs like muscle contraction, nerve transmission, etc).
- Eventually, calcium loss from the bones results in reduced bone density and this condition is known as osteoporosis. We will discuss osteoporosis in a bit.
- Calcium has a low bioavailability so anything that you can do to enhance, and therefore, improve calcium absorption is important.
- These are factors which enhance calcium’s bioavailability:
- Vitamin D:
- fortunately one of the best sources of calcium (milk) also contains Vitamin D. Women taking calcium supplements should also consider taking a calcium supplement that has some Vitamin D to help with absorption.
- Lactose:
- again, milk, our best calcium source also contains lactose. (What is lactose?)
- Gastric acid:
- is the acid secreted in your stomach for digestion; calcium absorption is enhanced in an acidic environment—since acid is secreted whenever you eat food, its best to take a calcium supplement with food.
- Need:
- any time you body needs more calcium, during pregnancy and periods of active growth such as infancy and adolescence, for example, our bodies can absorb more calcium
Factors which decrease Calcium absorption
- Too much fiber in the diet
- >35 gms/day
- for most Americans, this is not a problem, since the average fiber intake is ~10-15 gms/day
- Age
- As we age, we produce less gastric acid
- Excess use of laxatives
- Too much phosphorus in the diet
- Our main source of phosphorus is soda—and we drink a lot of soda, especially children and teens—which could be putting thier bones at risk, especially when they substitute soda for milk
- Vitamin D deficiency
- Too much coffee, tea
Osteoporosis
- a chronic, degenerative disease
- characterized by:
- bone loss
- decrease in bone density
- 2001:
- 1.5 million fractures annually
- costs $17 billion/yr ($47 million per day)
- prevention is key
. Bone loss from
osteoporosis
Normal bone
Bone loss occurs primarily in the
hips, spine and wrist
A DEXA scan is used to measure
bone density
- Osteoporosis is a major public health threat for an estimated 44 million Americans
- In the U.S. today, 10 million individuals are estimated to already have the disease and almost 34 million more are estimated to have low bone mass, placing them at increased risk for osteoporosis.
- Of the 10 million Americans estimated to have osteoporosis, eight million are women and 2 million are men.
- 34 million Americans, or 55% of the people 50 years of age and older, have low bone mass, which puts them at increased risk of developing osteoporosis and related fractures.
- Significant risk has been reported in people of all ethnic backgrounds.
- While osteoporosis is often thought of as an older person's disease, it can strike at any age
- 80% of those affected by osteoporosis are women.
- 20% of those affected by osteoporosis are men.
- One in two women and one in four men over age 50 will have an osteoporosis-related fracture in their lifetime.
- Osteoporosis is responsible for more than 1.5 million fractures annually, including:
- 300,000 hip fractures; and approximately
- 700,000 vertebral fractures,
- 250,000 wrist fractures; and
- 300,000 fractures at other sites.
Osteoporosis Risk Factors
- Increased age
- Being female
- Small boned, thin women
- People with a history of anorexia nervosa
- Caucasian/Asian women
- Family history
- Sedentary lifestyle
- Smoking, heavy drinking
- Long term use of certain medications such as prednisone
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Personal history of fracture after age 50
Current low bone mass
History of fracture in a 1° relative
Being female
Being thin and/or having a small frame
Advanced age
A family history of osteoporosis
Estrogen deficiency as a result of menopause, especially early or surgically induced
Abnormal absence of menstrual periods (amenorrhea)
Anorexia nervosa
Low lifetime calcium intake
Use of certain medications, such as corticosteroids and anticonvulsants
Low testosterone levels in men
An inactive lifestyle
Current cigarette smoking
Excessive use of alcohol
Being Caucasian or Asian, although African Americans and Hispanic Americans are at significant risk as well
- Remember what a risk factor is??
- It is something that increases the chances of developing a medical condition
- The more risk factors one has, the higher the chance of developing the medical condition. Having one or even 2 risk factors does not necessarily mean one will definitely develop a problem, just that the chances are higher.
Preventing Osteoporosis
- Consume adequate calcium and vitamin D in your diet-- throughout life
- Get regular physical activity, especially weight bearing exercise
- Be moderation in alcohol/caffeine consumption
- Prevention is key because currently, there is no cure
Treatment
- Hormone replacement therapy (estrogen)
- Calcium, vitamin D supplements
- Drugs
- Bisphosphonates
- Alendronate (brand name Fosamax®)
- Risedronate (brand name Actonel®)
- Calcitonin (brand name Miacalcin®)
- Raloxifene
- Bisphosphonates are a family of drugs used to prevent and treat osteoporosis.
- alendronate (Fosamax ®)
- etidronate (Didrocal ®)
- risedronate (Actonel ®).
- How do they work?
- Bisphosphonates bind permanently to the surfaces of the bones and slow down the osteoclasts (bone-eroding cells). This allows the osteoblasts (bone-building cells) to work more effectively.
- How effective are they?
- Bisphosphonates increase bone density and prevent fractures of the spine (vertebral fractures).
Calcium Needs
Women
age 19-50 1000 mg
> age 51 1200 mg
pregnancy 1000 mg
Men
age 19-50 1000 mg
Current average intake: 500-600 mg per day---only about half of what needs are
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Compare what is recommended to what our current intake is in the US:
500-600 mg/day
We only get about half our needs!
Food sources
milk, cheese, yogurt
foods made with milk/cheese (pudding, pizza)
Calcium fortified orange juice
Calcium fortified soy milk
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Calcium fortified orange juice and calcium fortified soy milk both have as much calcium in once serving as a glass of milk!
Calcium supplements
- Who should take them?
- people with lactose intolerance,
- people who dislike milk
- any one with a milk allergy (not the same thing as being lactose intolerant)
- Side effects of calcium supplements
- constipation, gas
- decreases iron absorption
- if you take an iron supplement for iron deficiency anemia, or to prevent anemia, take your calcium supplement and iron supplement at different times of the day
Tips for improving bioavailability from calcium supplements
calcium citrate is highly bioavailable (eg: Citracal)
take chewables (Tums with Calcium, Viactiv)
split your doses (take only 500 mg at a time)
take with food
don’t take more than 1500 mg/day
avoid oyster shell calcium, dolomite, bone meal, coral calcium
Phosphorus
Main functions:
- assists many enzymes/vitamins to extract energy from ATP—adenosine triphosphate
- component of cell membranes
- bone structure
Requirements
- same as calcium
- excess phosphorus, esp. combined with poor calcium intake, may contribute to bone loss
- Teens, or anyone, who drink a lot of soda and little or no milk are increasing the risk of bone loss…a real problem in the US
Deficiency
- None— we have problems with excessive intake in U.S.
Food sources
- Soft drinks, milk, cheese, baked goods, meat, food additives
Sodium (Na+)
Sodium chloride (NaCl) known as “table salt”
Main functions:
- fluid/water balance
- conduction of nerve impulses
- glucose transport/absorption
- acid-base balance
Physiological requirements: 500 mg/day
- This is the amount we need every day to prevent a deficiency
Average U.S intake: 5000-8000 mg/day
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The minimum amount of sodium you need each day is 500 mg. Compare this to the average amount Americans consume each day!
Recommended intake for good health <2400 mg/day
How does this compare with the average intake in the US?
A grain of salt
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A magnified view of a grain of salt.
Food sources
Table salt: 1 tsp = 2250 mg
Naturally occurring Na
Food serving size Na+ (mg)
milk 1 cup 120
meat (raw) 3 oz 50
fruits ---- <10
vegetables ½ cup 5-50
Sodium is naturally present in almost all foods—so it is impossible to have a sodium free diet
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Sodium is naturally present in almost all foods naturally. A cup of milk right from the cow contains 120 mg!
Sodium Added During Processing
Food serving size Na (mg)
ham 3 oz 1200
bologna 2 slices 580
canned soup 1 can 800-1000
cottage cheese 1 cup 920
McDonalds shake medium 300
dill pickle 1 whole 850
soy sauce 1 tbsp 1029
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- We get most of our sodium from salt added during processing…not from the salt we add at the table to foods.
- Remember what your physiological requirements are….if you eat one can of soup (not the low sodium kind) you are already consuming twice your needs and 1/3 of what is recommended for an entire day.
Sodium content of select foods
Taco bell bean burrito (1) 1100 mg
McD. Quarter Pounder w/cheese 1300mg
Pizza Hut Stuffed Crust Pizza (2 slices) 2850 mg
Chicken wings (12) 1750 mg
Kraft Mac and cheese (1 cup, prepared) 750 mg
Taco Bell Taco (1) 330 mg
American cheese (1 slice) 300 mg
BK Whopper 900 mg
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Processed foods and fast foods are generally high in sodium.
Sodium: major food sources
canned, cured, smoked meats
- bologna, salami, pepperoni, sausage, ham
canned soups
canned vegetables
Bouillon, Ramen noodles
olives, sauerkraut, anchovies
chips, crackers
seasonings (garlic salt, celery salt), MSG (monosodium glutamate)
some frozen dinners
Hypertension (high blood pressure)
Blood pressure
- the measurement of how hard your heart has to work to pump blood from your heart to the rest of your body
- Optimal blood pressure:
systolic <120
diastolic <80
Hypertension
Causes of hypertension:
1. No known cause
this type of hypertension occurs in 90-95% of people diagnosed with hypertension
2. Kidney disease
kidney disease is the cause of hypertension in only 5-10% of people with hypertension
- The cause of high blood pressure is unknown in the majority of cases….there are many risk factors, but the exact cause is not known. For a small percentage of the US population, kidney disease causes their high blood pressure.
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Symptoms
- None until significant organ damage has occurred
- Headaches, visual problems
- Hypertension is called the “silent killer” because there are no symptoms and therefore, most people do not know they have hypertension
Long term complications of uncontrolled hypertension
- stroke
- kidney disease
- blindness/impaired vision
- heart failure
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- Hypertension is known as “the silent killer” because you can have high blood pressure for years and years and yet never know it because there are no outward signs or symptoms.
- That is why regular monitoring is important, especially if you are at high risk. You can have your blood pressure checked free of charge at most supermarkets and pharmacies.
Hypertension
Risk Factors
- older age
- as we age, our blood pressure increases
- family history
- obesity
- diabetes/insulin resistance
- Type 1 or 2
- smoking, heavy alcohol intake
- African-American descent
- usually develop high BP at an earlier age and it can be more severe
- heart disease
Hypertension: Prevention
low to moderate sodium consumption
lose weight if overweight
eat a diet high in fruits, vegetables
consume low fat dairy products, whole grains
emphasize poultry, fish, nuts; eat less red meat
get some exercise
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These are the recommendations to reduce your risk of developing high blood pressure. If you already have high blood pressure, these recommendations can also help.
The DASH diet
- The DASH diet is a plan that has been clinically proven to help reduce blood pressure
- Information regarding the DASH diet is available at the following website.
- http://www.nhlbi.nih.gov/health/public/heart/hbp/dash/
- (Or download the pdf file about the dash diet linked on the syllabus)
- Read the article available at the CSPI website:
- http://www.cspinet.org/nah/dash.htm
Potassium
Main functions:
- conduction of nerve impulses
- critical in maintaining the heartbeat
- fluid and electrolyte balance
Deficiency:
- 90% we eat is absorbed
- potassium has a high bioavailability
- Low blood levels may be caused by:
- excessive vomiting, prolonged diarrhea, certain diuretics, laxative abuse
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bioavailability: refers to how much of the nutrient our bodies can actually absorb from foods.
Potassium
Toxicity
- can occur with potassium supplements (KCl)
Food sources
leafy greens (spinach)
oranges, orange juice, broccoli, bananas, tomatoes
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All fruits and vegetables contain potassium…those listed are especially high in potassium.