Different vitamins play different roles in the body, and a person requires a different amount of each vitamin to stay healthy. This article explains what vitamins are, what they do, and which foods are good sources.
Follow the links in blue below for more information about each vitamin. Vitamins are organic substances present in minute amounts in natural foodstuffs. Having too little of any particular vitamin may increase the risk of developing certain health issues. A vitamin is an organic compound, which means that it contains carbon. It is also an essential nutrient that the body may need to get from food. Vitamins A, D, E, and K are fat-soluble. The body stores fat-soluble vitamins in fatty tissue and the liver, and reserves of these vitamins can stay in the body for days and sometimes months.
Water-soluble vitamins do not stay in the body for long and cannot be stored. They leave the body via the urine. Because of this, people need a more regular supply of water-soluble vitamins than fat-soluble ones. Vitamin C and all the B vitamins are water-soluble.
Why is folate, another form of B9, important? Learn more about getting enough vitamin D. What are the symptoms of vitamin E deficiency? Your use of this information means that you agree to the Terms of Use and Privacy Policy. Learn How this information was developed. To learn more about Healthwise, visit Healthwise. All rights reserved. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.
Top of the page. Topic Overview The tables below list the vitamins , what they do in the body their functions , and their sources in food. Water-soluble vitamins Water-soluble vitamins travel freely through the body, and excess amounts usually are excreted by the kidneys.
Needed for vision, healthy skin and mucous membranes, bone and tooth growth, immune system health Vitamin A from animal sources retinol : fortified milk, cheese, cream, butter, fortified margarine, eggs, liver Beta-carotene from plant sources : Leafy, dark green vegetables; dark orange fruits apricots, cantaloupe and vegetables carrots, winter squash, sweet potatoes, pumpkin Vitamin D Needed for proper absorption of calcium ; stored in bones Egg yolks, liver, fatty fish, fortified milk, fortified margarine.
Vitamin E Antioxidant; protects cell walls Polyunsaturated plant oils soybean, corn, cottonseed, safflower ; leafy green vegetables; wheat germ; whole-grain products; liver; egg yolks; nuts and seeds Vitamin K Needed for proper blood clotting Leafy green vegetables such as kale, collard greens, and spinach; green vegetables such as broccoli, Brussels sprouts, and asparagus; also produced in intestinal tract by bacteria.
Top of the page Next Section: Related Information. Previous Section: Related Information Top of the page. Part of an enzyme needed for energy metabolism; important for normal vision and skin health.
Vitamin deficiency can cause health problems. Not eating enough fruits, vegetables, beans, lentils, whole grains and fortified dairy foods may increase your risk for health problems, including heart disease, cancer, and poor bone health osteoporosis.
Many people think that if some is good, a lot is better. This is not always the case. High doses of certain vitamins can be toxic. Ask your health care provider what is best for you. The Recommended Dietary Allowances RDAs for vitamins reflect how much of each vitamin most people should get each day. The best way to get all the daily vitamins you need is to eat a balanced diet that contains a wide variety of fruits, vegetables, fortified dairy foods, legumes dried beans , lentils, and whole grains.
Dietary supplements are another way to get the vitamins you need if the food you eat is not supplying enough vitamins. Supplements can be helpful during pregnancy and for special medical problems. Be very careful about taking large amounts of fat-soluble vitamin supplements. These include vitamins A, D, E, and K. These can build up in your body and may cause harmful effects. Vitamins, trace minerals, and other micronutrients. Goldman-Cecil Medicine.
Philadelphia, PA: Elsevier; chap Markell M, Siddiqi HA. Vitamins and trace elements. Editorial team. Print This Page Click to Print. Staying Healthy. Free Healthbeat Signup Get the latest in health news delivered to your inbox!
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I want to get healthier. Close Health Alerts from Harvard Medical School Get helpful tips and guidance for everything from fighting inflammation to finding the best diets for weight loss Close Stay on top of latest health news from Harvard Medical School. Sign me up. Beta carotene can easily be converted to vitamin A as needed. Essential for vision Lycopene may lower prostate cancer risk. Keeps tissues and skin healthy. Plays an important role in bone growth and in the immune system.
Diets rich in the carotenoids alpha carotene and lycopene seem to lower lung cancer risk. Carotenoids act as antioxidants. Foods rich in the carotenoids lutein and zeaxanthin may protect against cataracts. Sources of retinoids: beef liver, eggs, shrimp, fish, fortified milk, butter, cheddar cheese, Swiss cheese Sources of beta carotene: sweet potatoes, carrots, pumpkins, squash, spinach, mangoes, turnip greens. Many people get too much preformed vitamin A from food and supplements.
Large amounts of supplemental vitamin A but not beta carotene can be harmful to bones. Helps convert food into energy. Needed for healthy skin, hair, muscles, and brain and is critical for nerve function.
Pork chops, brown rice, ham, soymilk, watermelons, acorn squash. Most nutritious foods have some thiamin. Needed for healthy skin, hair, blood, and brain. Milk, eggs, yogurt, cheese, meats, green leafy vegetables, whole and enriched grains and cereals. Most Americans get enough of this nutrient. Essential for healthy skin, blood cells, brain, and nervous system.
Meat, poultry, fish, fortified and whole grains, mushrooms, potatoes, peanut butter. Niacin occurs naturally in food and can also be made by your body from the amino acid tryptophan, with the help of B 6. Helps make lipids fats , neurotransmitters, steroid hormones, and hemoglobin. Wide variety of nutritious foods, including chicken, egg yolk, whole grains, broccoli, mushrooms, avocados, tomato products.
Deficiency causes burning feet and other neurologic symptoms. Aids in lowering homocysteine levels and may reduce the risk of heart diseaseHelps convert tryptophan to niacin and serotonin, a neurotransmitter that plays key roles in sleep, appetite, and moods. Helps make red blood cells Influences cognitive abilities and immune function. Meat, fish, poultry, legumes, tofu and other soy products, potatoes, noncitrus fruits such as bananas and watermelons.
Many people don't get enough of this nutrient. Aids in lowering homocysteine levels and may lower the risk of heart disease. Assists in making new cells and breaking down some fatty acids and amino acids. Protects nerve cells and encourages their normal growth Helps make red blood cells and DNA. Meat, poultry, fish, milk, cheese, eggs, fortified cereals, fortified soymilk.
Some people, particularly older adults, are deficient in vitamin B 12 because they have trouble absorbing this vitamin from food. Those on a vegan or vegetarian diet often don't get enough B 12 as it's mostly found in animal products. They may need to take supplements. A lack of vitamin B 12 can cause memory loss, dementia, and numbness in the arms and legs.
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