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URL of this page: https://medlineplus.gov/definitions/vitaminsdefinitions.html

Definitions of Health Terms: Vitamins

Vitamins help our bodies grow and develop normally. The best way to get enough vitamins is to eat a balanced diet with a variety of foods. Knowing about different vitamins and what they do can help you to make sure you get enough of the vitamins that you need.

Find more definitions on   Fitness  |   General Health  |   Minerals  |   Nutrition  |  Vitamins

Antioxidants

Antioxidants are substances that may prevent or delay some types of cell damage. Examples include beta-carotene, lutein, lycopene, selenium, and vitamins C and E. They are found in many foods, including fruits and vegetables. They are also available as dietary supplements. Most research has not shown antioxidant supplements to be helpful in preventing diseases.
Source: National Institutes of Health, Office of Dietary Supplements

Daily Value (DV)

The Daily Value (DV) tells you what percentage of a nutrient one serving of that food or supplement provides compared to the recommended amount.
Source: National Institutes of Health, Office of Dietary Supplements

Dietary Supplements

A dietary supplement is a product you take to supplement your diet. It contains one or more dietary ingredients (including vitamins; minerals; herbs or other botanicals; amino acids; and other substances). Supplements do not have to go through the testing that drugs do for effectiveness and safety.
Source: National Institutes of Health, Office of Dietary Supplements

Fat-Soluble Vitamins

Fat-soluble vitamins include vitamins A, D, E, and K. The body stores fat-soluble vitamins in the liver and fatty tissues.
Source: National Institute of Diabetes and Digestive and Kidney Diseases

Folate

Folate is a B-vitamin that is naturally present in many foods. A form of folate called folic acid is used in dietary supplements and fortified foods. Our bodies need folate to make DNA and other genetic material. Folate is also needed for the body’s cells to divide. It is important for women to get enough folic acid before and during pregnancy. It can prevent major birth defects of the baby's brain or spine.
Source: National Institutes of Health, Office of Dietary Supplements

Multivitamin/Mineral Supplements

Multivitamin/mineral supplements contain a combination of vitamins and minerals. They sometimes have other ingredients, such as herbs. They are also called multis, multiples, or simply vitamins. Multis help people get the recommended amounts of vitamins and minerals when they cannot or do not get enough of these nutrients from food.
Source: National Institutes of Health, Office of Dietary Supplements

Niacin

Niacin is a nutrient in the vitamin B complex. The body needs it in small amounts to function and stay healthy. Niacin helps some enzymes work properly and helps the skin, nerves, and digestive tract stay healthy.
Source: National Cancer Institute

Recommended Dietary Allowance (RDA)

Recommended Dietary Allowance (RDA) is the amount of a nutrient you should get each day. There are different RDAs based on age, gender, and whether a woman is pregnant or breastfeeding.
Source: National Institutes of Health, Office of Dietary Supplements

Vitamin A

Vitamin A plays a role in your vision, bone growth, reproduction, cell functions, and immune system. Vitamin A is an antioxidant. It can come from plant or animal sources. Plant sources include colorful fruits and vegetables. Animal sources include liver and whole milk. Vitamin A is also added to foods like cereals.
Source: NIH MedlinePlus

Vitamin B6

Vitamin B6 is present in many foods and is added to other foods. The body needs vitamin B6 for many chemical reactions involved in metabolism. Vitamin B6 is involved in brain development during pregnancy and infancy. It also is involved in immune function.
Source: National Institutes of Health, Office of Dietary Supplements

Vitamin B12

Vitamin B12 helps keep the body’s nerve and blood cells healthy. It helps make DNA, the genetic material in all cells. Vitamin B12 also helps prevent a type of anemia that makes people tired and weak. Vitamin B12 is found naturally in a wide variety of animal foods. It is also added to some fortified foods and is found in most multivitamin supplements.
Source: National Institutes of Health, Office of Dietary Supplements

Vitamin C

Vitamin C is an antioxidant. It is important for your skin, bones, and connective tissue. It promotes healing and helps the body absorb iron. Vitamin C comes from fruits and vegetables. Good sources include citrus, red and green peppers, tomatoes, broccoli, and greens. Some juices and cereals have added vitamin C.
Source: NIH MedlinePlus

Vitamin D

Vitamin D helps your body absorb calcium. Calcium is one of the main building blocks of bone. A lack of vitamin D can lead to bone diseases such as osteoporosis or rickets. Vitamin D also has a role in your nerve, muscle, and immune systems. You can get vitamin D in three ways: through your skin (from sunlight), from your diet, and from supplements. Your body forms vitamin D naturally after exposure to sunlight. However, too much sun exposure can lead to skin aging and skin cancer, so many people try to get their vitamin D from other sources. Vitamin D-rich foods include egg yolks, saltwater fish, and liver. Some other foods, like milk and cereal, often have added vitamin D. You can also take vitamin D supplements. Check with your health care provider to see how much you should take.
Source: NIH MedlinePlus

Vitamin E

Vitamin E is an antioxidant. It plays a role in your immune system and metabolic processes. Most people get enough vitamin E from the foods they eat. Good sources of vitamin E include vegetable oils, margarine, nuts and seeds, and leafy greens. Vitamin E is added to foods like cereals. It is also available as a supplement.
Source: NIH MedlinePlus

Vitamin K

Vitamin K helps your body by making proteins for healthy bones and tissues. It also makes proteins for blood clotting. There are different types of vitamin K. Most people get vitamin K from plants such as green vegetables and dark berries. Bacteria in your intestines also produce small amounts of another type of vitamin K.
Source: NIH MedlinePlus

Vitamins

Vitamins are substances that our bodies need to develop and function normally. They include vitamins A, C, D, E, and K, choline, and the B vitamins (thiamin, riboflavin, niacin, pantothenic acid, biotin, vitamin B6, vitamin B12, and folate/folic acid).
Source: National Institutes of Health, Office of Dietary Supplements

Water-Soluble Vitamins

Water-soluble vitamins include all the B vitamins and vitamin C. The body does not easily store water-soluble vitamins and flushes out the extra in the urine.
Source: National Institute of Diabetes and Digestive and Kidney Diseases