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|Vitamin||What It Does For The Body|
|Vitamin A (Beta Carotene)||Promotes growth and repair of body tissues; reduces susceptibility to infections; aids in bone and teeth formation; maintains smooth skin|
|Vitamin B-1 (Thiamin)||Promotes growth and muscle tone; aids in the proper functioning of the muscles, heart, and nervous system; assists in digestion of carbohydrates|
|Vitamin B-2 (Riboflavin)||Maintains good vision and healthy skin, hair, and nails; assists in formation of antibodies and red blood cells; aids in carbohydrate, fat, and protein metabolism|
|Vitamin B-3 (Niacinamide)||Reduces cholesterol levels in the blood; maintains healthy skin, tongue, and digestive system; improves blood circulation; increases energy|
|Vitamin B-5||Fortifies white blood cells; helps the body's resistance to stress; builds cells|
|Vitamin B-6 (Pyridoxine)||Aids in the synthesis and breakdown of amino acids and the metabolism of fats and carbohydrates; supports the central nervous system; maintains healthy skin|
|Vitamin B-12 (Cobalamin)||Promotes growth in children; prevents anemia by regenerating red blood cells; aids in the metabolism of carbohydrates, fats, and proteins; maintains healthy nervous system|
|Biotin||Aids in the metabolism of proteins and fats; promotes healthy skin|
|Choline Folic Acid (Folate, Folacin)||Helps the liver eliminate toxins Promotes the growth and reproduction of body cells; aids in the formation of red blood cells and bone marrow|
|Vitamin C (Ascorbic Acid)||One of the major antioxidants; essential for healthy teeth, gums, and bones; helps to heal wounds, fractures, and scar tissue; builds resistance to infections; assists in the prevention and treatment of the common cold; prevents scurvy|
|Vitamin D||Improves the absorption of calcium and phosphorous (essential in the formation of healthy bones and teeth) maintains nervous system|
|Vitamin E||A major antioxidant; supplies oxygen to blood; provides nourishment to cells; prevents blood clots; slows cellular aging|
|Vitamin K (Menadione)||Prevents internal bleeding; reduces heavy menstrual flow|
vitaminsChemical compounds necessary for normal body function. Vitamins are needed for the proper synthesis of body building material, HORMONES and other chemical regulators; for the biochemical processes involved in energy production and nerve and muscle function; and for the breakdown of waste products and toxic substances. The B group of vitamins are COENZYMES without which many body ENZYMES cannot function normally. The amounts of vitamins needed for health are very small and are almost always present in adequate amounts in normal, well-balanced diets. Excess intake of vitamins A and D is dangerous. Vitamins C and E are antioxidants and may be valuable, in doses many times the minimum requirement, in combatting the damaging effect of FREE RADICALS. Folic acid supplements are valuable in preventing NEURAL TUBE DEFECTS. Vitamins are conventionally divided into the fat-soluble group A, D, E and K, and the water-soluble group, vitamin C (ascorbic acid) and the B vitamins-B1 (thiamine), B2 (riboflavine, riboflavin), nicotinic acid, B6 (pyridoxine), pantothenic acid, biotin, folic acid and B12. The term was derived from the belief that vitamins were ‘vital amines’.
vitaminsorganic substances that are necessary in the diet, in very small quantities, for normal growth and health: the recommended daily allowance (RDA) for any vitamin, widely quoted on food and drink labels, is less than 200 mg. Originally identified by alleviation of conditions caused by their deficiency (e.g. of scurvy in ships' crews in the 1750s by providing citrus fruit, the vital component being found later to be ascorbic acid, vitamin C). Nowadays hypovitaminosis due to lack of one or more vitamins is rare on a well-balanced diet, although occasionally an athlete may suffer from a deficiency, e.g. if dieting for weight loss or eliminating particular foods or food groups from the diet. hypervitaminosis can occur with excessive intake of one or more vitamins. The International Olympic Committee states that no vitamin supplements should be required if the diet is well balanced but athletes do often take them, especially vitamins C, B-complex and E, with a possible danger to their health by overconsumption. For sources, functions and deficiency effects, see Table 1.
|Vitamin||RNI (DoH 1991)||Sources||Action/functions||Deficiency||Excess||Special points|
|Vitamin B group|
|B1 Thiamin(e)||0.4 mg/1000 kcal||Fortified breakfast cereals, yeast extract, vegetables, fruit, wholegrain cereals, milk, liver, eggs, pork||Coenzyme for carbohydrate metabolism||Encephalopathy can occur with alcohol excess and low food intake. Beri-beri where polished rice is staple||Headache, insomnia, irritability, contact dermatitis||Requirement related to carbohydrate intake|
|B2 Riboflavin||Milk, milk products, offal, yeast extract, fortified breakfast cereals||Coenzyme for the metabolism of carbohydrate, fat and protein||Fissures at corners of mouth; tongue inflammation; corneal vascularization||No toxic effects, since large quantities are not absorbed||Destroyed by sunlight|
|B3 Niacin (nicotinic acid and nicotinamide)||6.6 mg/1000 kcal as nicotinic acid equivalents||Meat, fish, yeast extract, pulses, wholegrains, fortified breakfast cereals||Energy metabolism, as part of coenzymes NAD and NADP involved in oxidation and reduction reactions||Pellagra: dermatitis, diarrhoea and dementia||Liver damage, skin irritation||Also synthesized from the amino acid tryptophan|
|B5 Pantothenic acid||None set||Widespread in food, e.g. liver, eggs, yeast, vegetables, pulses, cereals||Protein, fat, carbohydrate and alcohol metabolism||Vomiting, insomnia||Not reported|
|B6 Pyridoxine||Meat, fish, eggs, some vegetables, wholegrains||Production of haemoglobin and of coenzymes involved in many metabolic processes||Rare. Metabolic and nervous system disorders||Peripheral nerve damage||Requirement is related to protein intake|
|Biotin||None set||Widely distributed in many foods, e.g. offal, egg yolk, legumes, etc. Can be synthesized by intestinal bacteria||Essential in fat metabolism||Rare; dermatitis, hair loss, nausea, fatigue and anorexia||None known|
|B12 Cobalamins||15 μg/g of protein||Animal products, meat, eggs, fish, dairy products, yeast extract||Anaemia; irreversible spinal cord damage||Not reported|
|Folates (folic acid)||200 μg/d||Green leaf vegetables, bread, fortified breakfast cereals, yeast extract, liver||Red blood cell production; DNA synthesis||Can mask the effects of B12 deficiency||Supplements before and during pregnancy reduce the incidence of spinal cord defects|
|Vitamin C ascorbic acid||40 mg/d||Collagen synthesis, formation of bones, connective tissue, teeth. Iron absorption for red blood cell production. Acts as an antioxidant||Sore mouth and gums; capillary bleeding; scurvy; delayed wound healing, scar break down||Diarrhoea; oxalate stones in kidneys||Destroyed by cooking in the presence of air and by plant enzymes released when cutting and grating raw food|
|Vitamin A retinol||As retinol in liver, kidney, oily fish, egg yolk, full-fat dairy produce. As the provitamin carotenes in green, yellow, orange and red fruit and vegetables, e.g. broccoli, carrots, apricots, mangoes, sweet potatoes and tomatoes||Visual pigments in retina, aids night vision. Normal growth and development of tissues; essential for healthy skin and mucosae. Acts as an antioxidant||Poor growth; rough dry skin and mucosae; xerophthalmia and eventual blindness; increased risk of infection; poor night vision||In pregnancy, high doses can cause fetal malformations||Synthesized in the body from carotenes present in the diet|
|Vitamin D cholecalciferol ergosterol||10 μg/d if housebound||Oily fish, egg yolk, butter, fortified margarine; action of ultraviolet rays (sunlight)||Calcium and phosphorus homeostasis||Rickets (children); osteomalacia (adults)||Rare; weight loss and diarrhoea||Produced in the body by action of sunlight on a provitamin in the skin: deficiency develops in those who are not exposed to sun|
|Vitamin E tocopherols tocotrienes||None set||Wheat germ, vegetable oils, nuts, seeds, egg yolk, cereals, dark green vegetables||Neurological abnormalities; anaemia: rare, from malnutrition or malabsorption||Muscle weakness, gastrointestinal disorders||Requirement is increased with increased intake of polyunsaturated fatty acids|
|Vitamin K phylloquinones menaquinones||None set||Green leafy vegetables, fruit and dairy products||Needed for the production of prothrombin and other coagulation factors||Impaired clotting; liver damage||Not so far observed from naturally occurring vitamin||Synthesized by intestinal bacteria so deficiency unusual|
Patient discussion about vitamins
Q. Should I take vitamins? I try to eat a healthy balanced diet everyday. Do I still need to take vitamins additionally?
Q. Are Vitamins really helpful? I realize that there's an entire industry around it but I was wondering how helpful vitamins really are. Is there a difference between vitamins from fruits and vegetables and vitamins that you buy off the shelve? Is there such a thing as taking too much vitamins?
Q. what vitamins are recommended for treating cold? and what is the right amount of it ?
You may read more here: http://www.nlm.nih.gov/medlineplus/commoncold.html