VITAMINS, COMMON INFORMATION

A vitamin (US /ˈvaɪtəmɪn/ or UK /ˈvɪtəmɪn/) is an organic compound required by an organism as a vital nutrient in limited amounts. An organic chemical compound (or related set of compounds) is called a vitamin when it cannot be synthesized in sufficient quantities by an organism, and must be obtained from the diet. Thus, the term is conditional both on the circumstances and on the particular organism. For example, ascorbic acid (vitamin C) is a vitamin for humans, but not for most other animals, and biotin (vitamin H) and vitamin D are required in the human diet only in certain circumstances.

Thiamin What it does: helps convert the food we eat to the energy we need Foods that have thiamin: spinach, tomato juice, watermelon, sunflower seeds, ham Deficiency problems: weakness, tingling in feet and hands, poor coordination
Riboflavin - named for its yellow color (flavus means yellow in Latin) What it does: helps convert the food we eat to the energy we need Foods that have riboflavin: milk, cheese, liver, broccoli, asparagus, spinach Deficiency problems: eye disorders, cracks at corners of mouth, swollen tongue
Niacin What it does: helps our body use the fat and sugar we eat for energy helps keep our skin healthy Foods that have niacin: mushrooms, tuna, green beans, broccoli, spinach, breakfast cereals Deficiency problems: diarrhea, skin problems, mental disorientation
Vitamin B6 What it does: helps make red blood cells helps our body use the fat and protein we eat for energy Foods that have vitamin B6: spinach, broccoli, tomato juice, banana, watermelon, chicken breast Deficiency problems: headache, convulsions, vomiting, flaky skin, sore tongue
Folate What it does: helps to make new cells helps prevent heart disease Foods that have folate: asparagus, broccoli, corn flakes, green beans, tomato juice, beans Deficiency problems: diarrhea, mental disorders, poor growth
Vitamin B12 What it does: helps to make new cells Foods that have vitamin B12: meat, fish, poultry, milk, cheese, eggs Deficiency problems: anemia, poor nerve function
Vitamin C- almost all animals make vitamin C in their bodies (only humans, guinea pigs, some bats, and some fish don't) What it does: protects cells from damage helps keep bones and skin healthy may help prevent cancer and heart disease Foods that have vitamin C: oranges, strawberries, peppers, kiwi, brussel sprouts, broccoli, spinach Deficiency problems: bleeding gums, tiredness, weakness, sore muscle

Vitamin A - discovered in 1913 What it does: helps with eyesight keeps skin healthy helps with growth of body organs (like bones) Foods that have vitamin A: liver, fish, milk, butter, eggs, carrots Deficiency problems: night blindness, poor growth, dry skin
Vitamin D - made in the skin by the sun What it does: helps bones grow strong Foods that have vitamin D: egg yolks, liver, butter, milk Deficiency problems: rickets (deformed bones), weak bones
Vitamin E - called the antiaging vitamin What it does: protects lungs against pollution damage helps keep heart healthy may help protect against cancer Foods that have vitamin E: sweet potatoes, peanut butter, sunflower seeds, spinach, nuts Deficiency problems: nerve destruction, red blood cell destruction
Vitamin K - made by bacteria in our intestines What it does: helps make blood clot helps keep bones healthy Foods that have vitamin K: liver, cabbage, lettuce, spinach, milk, meat, eggs Deficiency problems: hemorrhage

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By convention, the term vitamin includes neither other essential nutrients, such as dietary minerals, essential fatty acids, or essential amino acids (which are needed in larger amounts than vitamins) nor the large number of other nutrients that promote health but are otherwise required less often. Thirteen vitamins are universally recognized at present.

Vitamins are classified by their biological and chemical activity, not their structure. Thus, each "vitamin" refers to a number of vitamer compounds that all show the biological activity associated with a particular vitamin. Such a set of chemicals is grouped under an alphabetized vitamin "generic descriptor" title, such as "vitamin A", which includes the compounds retinal, retinol, and four known carotenoids. Vitamers by definition are convertible to the active form of the vitamin in the body, and are sometimes inter-convertible to one another, as well.

itamins have diverse biochemical functions. Some, such as vitamin D, have hormone-like functions as regulators of mineral metabolism, or regulators of cell and tissue growth and differentiation (such as some forms of vitamin A). Others function as antioxidants (e.g., vitamin E and sometimesvitamin C). The largest number of vitamins, the B complex vitamins, function as precursors for enzyme cofactors, that help enzymes in their work as catalysts in metabolism. In this role, vitamins may be tightly bound to enzymes as part of prosthetic groups: For example, biotin is part of enzymes involved in making fatty acids. They may also be less tightly bound to enzyme catalysts as coenzymes, detachable molecules that function to carry chemical groups or electrons between molecules. For example, folic acid may carry methyl, formyl, and methylene groups in the cell. Although these roles in assisting enzyme-substrate reactions are vitamins' best-known function, the other vitamin functions are equally important.

Until the mid-1930s, when the first commercial yeast-extract vitamin B complex and semi-synthetic vitamin C supplement tablets were sold, vitamins were obtained solely through food intake, and changes in diet (which, for example, could occur during a particular growing season) usually greatly altered the types and amounts of vitamins ingested. However, vitamins have been produced as commodity chemicals and made widely available as inexpensive semisynthetic and synthetic-source multivitamin dietary and food supplements and additives, since the middle of the 20th century.,,,,,,,

List of vitamins

Each vitamin is typically used in multiple reactions, and, therefore, most have multiple functions.

Vitamin generic descriptor name	Vitamerchemical name(s) (list not complete)	Solubility	Recommended dietary allowances (male, age 19–70)[6]	Deficiency disease	Upper Intake Level (UL/day)[6]	Overdose disease	Food sources
Vitamin A	Retinol, retinal, and four carotenoids including beta carotene	Fat	900 µg	Night-blindness,Hyperkeratosis, andKeratomalacia[7]	3,000 µg	Hypervitaminosis A	Orange, ripe yellow fruits, leafy vegetables, carrots, pumpkin, squash, spinach, liver, soy milk, milk
Vitamin B1	Thiamine	Water	1.2 mg	Beriberi, Wernicke-Korsakoff syndrome	N/D[8]	Drowsiness or muscle relaxation with large doses.[9]	Pork, oatmeal, brown rice, vegetables, potatoes, liver, eggs
Vitamin B2	Riboflavin	Water	1.3 mg	Ariboflavinosis	N/D		Dairy products, bananas, popcorn, green beans, asparagus
Vitamin B3	Niacin, niacinamide	Water	16.0 mg	Pellagra	35.0 mg	Liver damage (doses > 2g/day)[10] and other problems	Meat, fish, eggs, many vegetables, mushrooms, tree nuts
Vitamin B5	Pantothenic acid	Water	5.0 mg[11]	Paresthesia	N/D	Diarrhea; possibly nausea and heartburn.[12]	Meat, broccoli, avocados
Vitamin B6	Pyridoxine,pyridoxamine,pyridoxal	Water	1.3–1.7 mg	Anemia[13] peripheral neuropathy.	100 mg	Impairment ofproprioception, nerve damage (doses > 100 mg/day)	Meat, vegetables, tree nuts, bananas
Vitamin B7	Biotin	Water	30.0 µg	Dermatitis, enteritis	N/D		Raw egg yolk, liver, peanuts, certain vegetables
Vitamin B9	Folic acid, folinic acid	Water	400 µg	Megaloblastic anemiaand Deficiency during pregnancy is associated with birth defects, such as neural tube defects	1,000 µg	May mask symptoms of vitamin B12 deficiency;other effects.	Leafy vegetables, pasta, bread, cereal, liver
Vitamin B12	Cyanocobalamin,hydroxycobalamin,methylcobalamin	Water	2.4 µg	Megaloblastic anemia[14]	N/D	Acne-like rash [causality is not conclusively established].	Meat and other animal products
Vitamin C	Ascorbic acid	Water	90.0 mg	Scurvy	2,000 mg	Vitamin C megadosage	Many fruits and vegetables, liver
Vitamin D	Cholecalciferol	Fat	10 µg[15]	Rickets andOsteomalacia	50 µg	Hypervitaminosis D	Fish, eggs, liver, mushrooms
Vitamin E	Tocopherols,tocotrienols	Fat	15.0 mg	Deficiency is very rare; mild hemolytic anemiain newborn infants.[16]	1,000 mg	Increased congestive heart failure seen in one large randomized study.[17]	Many fruits and vegetables, nuts and seeds
Vitamin K	phylloquinone,menaquinones	Fat	120 µg	Bleeding diathesis	N/D	Increases coagulation in patients taking warfarin.[18]	Leafy green vegetables such as spinach, egg yolks, liver