Vitamins: Their Functions and Sources

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 overindulgence amounts normally are excreted by the kidneys. The body needs water-soluble vitamins in patronize, small doses. These vitamins are not vitamin a probably as fat-soluble vitamins to reach toxic levels. But niacin, vitamin B6, vitamin bc, choline, and vitamin C have upper consumption limits. Vitamin B6 at high levels over a long time period of time has been shown to cause irreversible boldness price. A poise diet normally provides adequate of these vitamins. People older than 50 and some vegetarians may need to use supplements to get enough B12.
Water-soluble vitamins

nutrient

function
Sources
Thiamine ( vitamin B1 )
separate of an enzyme needed for energy metamorphosis ; important to nerve officiate
Found in all alimentary foods in centrist amounts : pork, whole-grain or enriched breads and cereals, legumes, nuts and seeds
Riboflavin ( vitamin B2 )
part of an enzyme needed for energy metabolism ; important for normal vision and skin health
milk and milk products ; leafy green vegetables ; whole-grain, enriched breads and cereals
Niacin ( vitamin B3 )
separate of an enzyme needed for energy metamorphosis ; significant for nervous system, digestive organization, and skin health
kernel, poultry, pisces, whole-grain or enriched breads and cereals, vegetables ( specially mushrooms, asparagus, and leafy k vegetables ), peanut butter
Pantothenic acidic
part of an enzyme needed for energy metabolism
widespread in foods
biotin
partially of an enzyme needed for energy metabolism
widespread in foods ; besides produced in intestinal nerve pathway by bacteria
Pyridoxine ( vitamin B6 )
part of an enzyme needed for protein metabolism ; helps make red lineage cells
meat, fish, poultry, vegetables, fruits
Folic acidic
separate of an enzyme needed for making DNA and new cells, particularly bolshevik lineage cells

Leafy green vegetables and legumes, seeds, orange juice, and liver-colored ; now added to most elegant grains
Cobalamin ( vitamin B12 )
separate of an enzyme needed for making new cells ; significant to nerve routine
kernel, domestic fowl, pisces, seafood, eggs, milk and milk products ; not found in plant foods
Ascorbic acidic ( vitamin C )
Antioxidant ; part of an enzyme needed for protein metabolism ; significant for immune system health ; aids in cast-iron concentration
Found only in fruits and vegetables, particularly citrus fruits, vegetables in the boodle family, cantaloup, strawberries, peppers, tomatoes, potatoes, lettuce, papaya, mangoes, kiwifruit

Fat-soluble vitamins

fat-soluble vitamins are stored in the body ‘s cells and are not excreted vitamin a well as water-soluble vitamins. They do not need to be consumed vitamin a frequently as water-soluble vitamins, although adequate amounts are needed. If you take excessively much of a fat-soluble vitamin, it could become toxic. Your body is specially sensitive to excessively much vitamin ampere from animal sources ( vitamin a1 ) and besides much vitamin D. A balanced diet normally provides adequate fat-soluble vitamins.
Fat-soluble vitamins

food
affair
Sources
Vitamin A ( and its precursor*, beta-carotene )
*A precursor is converted by the body to the vitamin .
Needed for sight, healthy skin and mucous membranes, bone and tooth growth, immune system health
Vitamin ampere from animal sources ( vitamin a1 ) : fortified milk, cheese, skim, butter, fortified margarine, eggs, liver
Beta-carotene ( from plant sources ) : Leafy, benighted green vegetables ; colored orange fruits ( apricots, cantaloup ) and vegetables ( carrots, winter squash, gratifying potatoes, pumpkin )
Vitamin D
Needed for proper concentration of calcium ; stored in bones
egg yolks, liver, fatso fish, fortified milk, fortify margarine. When exposed to sunlight, the skin can make vitamin D .
Vitamin E
Antioxidant ; protects cell walls
Polyunsaturated plant oils ( soy, corn, cottonseed, safflower ) ; leafy green vegetables ; pale yellow germ ; whole-grain products ; liver ; egg yolks ; nuts and seeds

Vitamin K
Needed for proper lineage curdling
Leafy green vegetables such as boodle, collard greens, and spinach ; green vegetables such as broccoli, brussels sprouts, and asparagus ; besides produced in intestinal nerve pathway by bacteria