Vitamins and Minerals PDF

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Vitamins and Minerals  Vitamins and minerals are used for metabolic processes.  They are required for muscle contractions and energy expenditure.  They are key regulators in exercise and physical activity.  The intensity, duration, and frequency of physical activity affect vitamin and mineral (micronutrient) requirements. Dietary Reference Intake  DRI: nutrient recommendations for healthy, moderately active people  RDA: Recommended Dietary Allowance: dietary intake level that is adequate for approximately 98% of healthy people.  AI: Adequate Intake: estimated value that is used when an RDA cannot be determined  EAR: Estimated Average Requirement: a value used to approximate the nutrient needs of half of the healthy people in a group  UL: Upper Limit: is the highest amount of a nutrient that most individuals can consume without adverse effects Classification of Vitamins  Vitamins are classified by their solubility within the body.  Water-soluble vitamins (B complex and C) do not require fat for absorption, are not stored in the body, and are less likely to be toxic at high doses.  Fat-soluble vitamins (A,D,E,K) are more soluble in organic solvents and more likely to be toxic at high doses.

Water-Soluble Vitamins Vitamin Effects of Exercise

Rec. Intake for

Food Source

Comments

on Requirement Vitamin B-6

Athletics RDA

Exercise does not cause changes in B-6 status.

Liver, chicken, bananas, potatoes, spinach

Vitamin D-12

Exercise does not seem to increase needs

RDA

Fish, milk, milk products, eggs, meat, poultry, fortified cereals

Folate

Exercise does not seem to increase needs.

RDA

Leafy greens, dry beans, peas, grains, fortified cereals

Thiamine

Exercise does not seem to increase needs.

RDA

Wheat germ, brewer’s yeast, oysters, beef liver, peanuts, green peas, raisins, collard greens

Riboflavin

Exercise does not seem to increase needs.

RDA

Organ meats, milk, cheese, oily fish, eggs, dark leafy green vegetables

Niacin

Exercise does not seem to increase needs.

RDA

Beef, pork, chicken, wheat flour, eggs, milk

Vegan athletes may need to supplement to ensure adequate intake.

Ergogenic effects are equivocal; positive effects are not strong.

Does not seem to have ergogenic effects; more research

needed. Pantothenic acid

Not enough info

AI

Eggs, whole grain cereals, meat

Biotin

Not enough information

AI

Kidney, liver, eggs, dried mixed fruit

Vitamin C

Increased intakes may prevent upper respiratory infections.

At least RDA, endurance athletes need more than RDA, but less than UL.

Dark green leafy vegetables, broccoli, chili and bell peppers, tomato, kiwi, oranges, papaya, strawberries

Strong antioxidant properties reported for endurance and athletes.

Choline

Exercise does not seem to increase needs.

AI

Liver, egg yolks, peanuts, cauliflower, soybeans, grape juice, cabbage

Does not seem to have ergogenic effect; more research needed.

Absorbtion and Bioavilability  The amount of a vitamin absorbed by the gut and made available to the body may be very different from the amount of the vitamin measured in the raw food  Bioavailability depends on dietary form of the vitamin, other substances in the diet, drugs a person is taking, age, general health, environmental conditions, cooking method Dietary intake  All grains in the U.S. are enriched with niacin, riboflavin, thiamine, iron, and folic acid.  There are no reports of low intakes of thiamine, riboflavin, or niacin.  Research shows that unless a person is restricting energy intake or consuming a diet high in refined foods, nutrient intakes of thiamine, riboflavin, vitamin B6 and niacin appear to be adequate.

Whole Grains vs. Enriched Grains

Vitamines and Exercise Performancde  To date, data does not support improved exercise performance in individuals who supplement with vitamins or minerals as long as nutrient status was good before supplementation began.  If deficient in a vitamin, an athlete’s performance could benefit, and once vitamin status has normalized, additional supplementation will not continue to improve performance. Fat-Soluble Vitamins  Fat-soluble vitamins are absorbed with the ingestion of dietary fat.  Fat-soluble vitamins are stored in the liver and fatty tissues and are eliminated much more slowly than water-soluble vitamins.  Small amounts of vitamin A, vitamin D, vitamin E and vitamin K are needed to maintain good health.  Mega doses of vitamins A, D, E or K can be toxic.

Vitamin D  Activated vitamin D is a seco-steroid hormone.  Cutaneous production of vitamin D from incidental ultraviolet B (UVB) radiation in sunlight, NOT dietary intake, is the principal source of circulating vitamin D stores in the body.  Most natural human diets are low in vitamin D, except those that include large quantities of wild caught fatty fish.  Without adequate vitamin D, humans can only absorb 10-15% of dietary calcium. Factors Affecting Vitamin D Production

Latitude, season of the year, time of day: o UVB radiation is effectively absent early and late in the day and for entire months during the winter in locations above 35˚ latitude.  Amount of time spent indoors, sun block, clothing covering skin, age: o Increases in each of these factors decreases cutaneous vitamin D production.  Melanin content of the skin: o Those with higher concentrations of melanin in their skin need up to 10 times longer UVB exposure to generate the same stores of 25 (OH)D of a fair skinned person.  A young, Caucasian male who forgets to put on sunscreen, running in shorts on a summer day in Kenya likely has great Vitamin D production and thus sufficient levels.  An African American male running in sweats and a beanie in November in Michigan likely has lower Vitamin D production and thus is likely to be deficient. What Athletes Can Do  Get some sunshine: o Get 15 minutes of full body sun in the peak sunshine of the day (noon) 2x/week 



before applying sunscreen. o Longer than 15 minutes is needed for darker skin. Eat vitamin D-rich food sources o Oily/fatty fish, cod liver oil, dried shitake mushrooms o Fortified foods such as milk, orange juice and cereal

 Supplement safely at 600 IU/day. Minerals  Minerals are inorganic substances found naturally on earth and are essential nutrients necessary for the building and repair of muscle tissue, healthy immune function, and cell reproduction. 

Based on their daily requirements, minerals are usually classified as: o Macro-minerals or major minerals  Sodium, potassium, chloride, calcium, phosphorus and magnesium  Daily dietary allowance is >100mg/day. o Micro-minerals or trace minerals

 Iron, zinc, copper, chromium and selenium  Daily dietary need is...