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Vitamins are essential for good health. Healthy food choices can help ensure you're getting your share.
Vitamins are organic substances—compounds found naturally in small amounts in plants and animals. Some can also be produced in a laboratory. These are called synthetic vitamins.
Vitamins are needed to maintain the normal body functions that support growth, health and reproduction. Some help convert food to energy, and others are necessary for processes such as the formation of DNA and blood clotting.
There are 13 vitamins necessary for the human body to work properly. They are vitamins A, C, D, E, K, and the B vitamins. The B vitamin group includes B6, B12, biotin, folate, thiamine, pantothenic acid, niacin and riboflavin.
Dietary Reference Intakes (DRIs) for vitamins are available at the U.S. Department of Agriculture's Food and Nutrition Information Center. DRIs have been established by the Health and Medicine Division of the National Academies of Sciences, Engineering, and Medicine. DRIs vary depending on a person's age and sex.
The ideal way to get enough vitamins is from eating a wide variety of foods, according to the Academy of Nutrition and Dietetics. Check the U.S. Department of Agriculture's DRI Nutrient Reports and the U.S. Food and Drug Administration's Nutrition Facts panel on food labels for help. Normal, healthy children and adults do not need to take vitamin supplements. However, before and during pregnancy, women should be sure they get enough folic acid, which can prevent birth defects. Before pregnancy, March of Dimes recommends 400 micrograms daily, and during pregnancy, 600 micrograms.
Foods that are rich in vitamins include:
- Broccoli; spinach and other green, leafy vegetables; carrots; peppers; tomatoes; potatoes; strawberries; and citrus fruits.
- Enriched or whole-grain products, oats, brown rice, dried beans and peas, soybeans, and nuts.
- Meat, poultry, fish, liver, kidney, eggs and dairy products.
People who may need vitamin supplements include:
- Pregnant women.
- Women who may become pregnant.
- Breastfed or partially breastfed babies.
- People over age 50.
- Postmenopausal women.
Natural and synthetic forms of a vitamin do not work differently, except in the case of vitamin E. The natural form of this vitamin is easier for the body to use than the synthetic form.
The effects of vitamin deficiency depend on the vitamin and how much of it you're lacking.
Mild deficiencies can cause impaired immunity, anemia, dermatitis, irritability, lethargy, weakness and mental confusion. Folate deficiency may cause birth defects.
Severe deficiencies can cause blindness, permanent nerve damage, scurvy, rickets and bone loss.
Taking excess amounts of vitamins can cause problems including nerve, liver and kidney damage; headaches; nausea and vomiting; diarrhea; itching; and jaundice, depending on the vitamin.
To learn more about vitamins, visit the Vitamins health topic center. You can also find out more about vitamins at these websites:
- Food and Nutrition Information Center.
- The National Institutes of Health Office of Dietary Supplements.