Vitamins & Minerals

Nancy Brockel Kaufman, Food & Nutrition Specialist
Pat Beck, Nutrition Specialist
Karen Heller, Food & Nutrition Specialist

It has long been known that vitamins and minerals are essential nutrients for the human body. But you may wonder what these nutrients do for the body, how much is enough and how much is too much. The following information should help answer these questions. It tells what various vitamins and minerals do for the body, in what foods they are found and what the Recommended Dietary Allowances and potential overdose risks are for each.

Taking an overdose means giving the body vitamins and minerals in a quantity greater than is necessary. Excess of a particular vitamin or mineral can pose risks as serious to health as a deficiency of that nutrient. Nutrients are interrelated and an excess of one nutrient can upset the balance the body requires of other nutrients. A variety of healthful foods eaten in moderation will likely supply the body with the nutrients it needs. Usually a vitamin/mineral supplement is not necessary.

The Recommended Dietary Allowances (RDA) can provide guidance in determining the amounts of nutrients needed by the body. The RDAs are the amounts of nutrients essential to meet the known nutritional needs of nearly all healthy persons in America. The RDAs given in this publication are for adult men and women ages 25 to 50.

Minerals	RDA	Function	Major sources	Food combination that meet RDA for one day	Risks of overdose
1. Calcium	800 mg	Assists in clotting of blood and building of bones and teeth. Promotes proper functioning of nerves, heart and muscle.	All forms of milk, cheese (except cottage cheese and cream cheese) and ice cream.	Milk (3 8-oz servings) OR pudding (1 c) with cheddar cheese (1� oz) and ice cream (1� C).	Drowsiness, lethargy, nausea; high amounts may lead to calcium deposits in soft tissues, especially the kidneys.
2. Iodine	150 ug	Promotes proper functioning of thyroid gland.	Seafood, iodized salt.	Use of iodized salt.	Very high doses may impair normal functioning of the thyroid gland.
3. Iron	10 mg(m) 15 mg(f)	Makes hemoglobin, the red substance in blood. Transports oxygen to and from cells.	Organ meats, oysters, lean meats, eggs, leafy green vegetables, dried peas and beans, enriched breads and cereals.	Red kidney beans (1 c) with ground beef (3 oz) with beef liver (3 oz), with bread (4 servings). (It is difficult women to meet the RDA for iron on a typical American diet.)	Too much can be lethal. About 2,000 cases of iron poisoning occur each year in the U.S., mainly in young for children who take their parents' iron supplements.
4. Magnesium	350 mg(m) 280 mg(f)	Needed for contraction of nerves and muscles and for normal metabo- of potassium and calcium. Activates many- enzyme systems, involved in carbohydrate metabolism and protein synthesis.	Nuts, whole grains, dried peas and beans, milk, green leafy vegetables.	100% bran ready-to-eat cereal (1 oz) with 2% milk (16 oz OR 2 cups) with pinto beans (3/4 C).	Large amounts may have a cathartic effect (cathartic means to purge, cleanse). Frequent use of magnesium- containing antacids or laxatives may cause drowsiness, lethargy, profuse sweating, slurring of speech and unsteadiness. Thirty ml (2 tablespoons) of milk of magnesia provides 1,000 mg of magnesium which is 3 to 4 times the average dietary intake. Only 20 to 30 percent of 1,000 mg is absorbed - but combined with diet could result in excess Large amounts might cause serious problems for people with kidney impairment.
5. Phosphorus	800 mg	With calcium, helps build bones and teeth, aids in release of energy from carbohydrates, fat and protein; aids in formation of genetic material and cell membranes.	Meat, poultry, fish, eggs, dried peas and beans, milk and milk products.	Milk (2 8-oz servings of 2%) with ground beef (3 oz lean with 10% fat) with chicken breast (3 oz).	High phosphorus intake occurring with a high-protein diet and low-calcium intake may present risks to the elderly and post-menopausal women by promoting calcium deficiency.
6. Zinc	15 mg(m) 12 mg(f)	Constituent of many enzymes important in metabolism, aids in wound healing, needed for normal growth, especially during childhood, and for normal taste sensation.	Meat, fish, egg yolk, milk, oysters, whole grains.	Pork liver (3 oz) with egg (1 hard cooked) with milk (16 oz of 2%) with 2 chicken legs (including meat and skin fried with flour coating) with cheddar cheese (1 oz).	Anemia, nausea, reproductive problems, vomiting.
7. Selenium	70 mg(m) 55 mg(f)	With vitamin E, helps protect cells from oxidative damage; involved in fat metabolism.	Seafood, kidney, liver, meat, cereals.	Canned tuna (3 oz) OR barley cereal (4 oz) with skim milk (1 c).	Nausea, diarrhea, fatigue, hair hair loss, fingernail tenderness, irritability.
Fat Soluble
8. Vitamin A	1,000 ug RE(m) 800 ug RE(f)	Helps eyes adjust to dim light. Helps keep skin and lining of mouth, nose, throat and digestive tract healthy and resistant to infection.	Liver, butter, cream, whole milk, cheese, egg yolk, dark green leafy vegetables, yellow and orange fruits and vegetables, fortified products.	Raw carrot (1 small) OR cooked broccoli, (� C) with cheddar cheese (1 oz) and peach (1 med.).	Nausea, headache, vomiting, irritability, blurred vision, hair loss, widespread itching, abnormal bone growth.
9. Vitamin D	5 ug	Helps body use calcium and phosphorus to build and maintain strong bones and teeth.	Fortified milk, exposure to sunlight, fatty fish, eggs, liver, butter.	Normal adults can usually meet needs by exposure to sunlight. Two cups of fortified milk provides 5 ug of vitamin D. If vitamin D is added, 1 quart milk contains 400 IU or 10 ug.	Loss of appetite, nausea headache, excessive urination, diarrhea or constipation, weakness, fatigue, kidney damage from calcium deposits, injury to arterial walls, high blood pressure, elevated blood cholesterol and mental depression.
10. Vitamin E	10 mg TE (m) 8 mg TE (f)	Helps keep red blood cells intact. An antioxidant, protects vitamin A and essential fatty acids from oxidation. Helps maintain normal muscle metabolism.	Vegetable oils, especially wheat germ oil, margarine.	Present knowledge indicates that balanced diet supplies adequate Vitamin E. One tablespoon of sunflower oil has 6.1 mg TE vitamin E.	May raise blood cholesterol and blood tricycerides, may slightly reduce thyroid hormones, nausea, diarrhea, headache, rapid pulse, itchy rash, extreme fatigue, muscle weakness, blurred vision.
11. Vitamin K	80 mg(m) 65 mg(f)	Involved in synthesis of proteins required for blood clotting	Green leafy vegetables, dairy products, meats, eggs, cereals, fruits.	Raw broccoli (1/2 c) OR beef liver (3 oz) OR cooked green peas (1/2 c).	No cases of toxicity have been reported.
Water Soluble
12. Vitamin C	60 mg	Helps hold body cells together and strengthens walls of blood vessels; helps in healing wounds; helps body to build bones and teeth; aids in the absorption of iron.	Citrus fruits, green peppers, tomatoes, strawberries, cantaloupe, cabbage, broccoli, kale, potatoes.	Orange juice (1/2 c reconstituted, frozen) OR cooked broccoli (1/2 c).	Diarrhea, can increase risk of developing kidney stones, false positive urine tests for diabetes, damage to tooth enamel, especially from chewable type. If one is taking a dose and then stops abruptly, deficiency symptoms can result. (Reduce amount or dosage gradually to prevent this.)
13. Thiamin (B₁)	1.5 mg(m) 1.1 mg(f)	Helps body cells obtain energy from food. Helps keep nerves in healthy condition. Promotes good appetite and digestion.	Pork, liver and other organs, wheat germ, whole grain or enriched cereals and breads, soybeans, peanuts and other legumes and milk.	Pork roast (3 oz) with bread (3 servings) with peanuts (1 oz) and milk (2 c).	Headache, irritability, insomnia, rapid pulse, weakness edema.
14. Riboflavin (B₂)	1.7 mg(m) 1.3 mg(f)	Aids in utilization of protein, fat and carbohydrate for energy. Promotes healthy skin, eyes, clear vision.	Milk, organ meats and enriched breads and cereals.	Milk (2 c) with enriched bread (3 servings) and winter (orange) squash (1/2 c).	No cases of toxicity have been reported.
15. Niacin	19 mg(m) 15 mg(f)	Helps body cells produce energy from food. Helps to maintain health of skin, tongue, digestive tract and nervous system.	Lean meat, fish, poultry, liver, kidney, whole wheat and enriched cereals and breads, peanuts.	Chicken (3 oz) with ground beef (3 oz) and enriched bread (2 slices).	Large doses may cause flushing of skin, headache, cramps, widespread itching, skin peeling and liver damage. Large doses may lower cholesterol; however, side effects like irregular heart beat, stomach discomfort and abnormal blood levels of enzymes, sugar and uric acid discourage its use.
16. Folacin	200 ug(m) 180 ug(f)	Needed for normal productions of red and white blood cells, proper development of fetus and infants, maintenance of a healthy adult nervous system, maintains normal functioning of the gastrointestinal tract, and manufacture of basic cell genetics (RNA and DNA).	Liver, yeast, deep green leafy vegetables, avocado, oranges and orange juice, navy, lentil and lima beans.	Pork liver (3 oz braised) with avocado (1 med.), with orange juice (8 oz frozen, reconstituted).	A high intake may mask symptoms of pernicious anemia, a serious problem.
17. Pyridoxine (B₆)	2.0 mg(m) 1.6 mg(f)	Needed for protein metabolism. Helps to build blood cells.	Meat, liver, kidney, whole grain cereals, peanuts, green leafy vegetables.	One cup of 100% bran cereal.	Large doses may cause severe nervous system dysfunction; for example, a spastic gait. The action of L-dopa, a drug used to treat Parkinson's disease, may be blocked by 5 mg of B₆ daily.
18. Cobalamin (B₁₂)	2 ug	Needed to build healthy red blood cells. Needed for normal growth in children	Found only in foods of animal origin, like liver, meat, milk, eggs, cheese.	Milk (2 c of 2%) with eggs (2 hard cooked).	No cases of toxicity have been reported.

The information given herein is for educational purposes only. Reference to commercial products or trade names with the understanding that no discrimination is intended and no endorsement by NDSU Extension Service is implied.