Vitamins, Minerals and Dietary Supplements Guidelines. Vitamin - Wikipedia. A vitamin is an organic compound and a vital nutrient that an organism requires in limited amounts.
An organic chemical compound (or related set of compounds) is called a vitamin when the organism cannot synthesize the compound in sufficient quantities, and it must be obtained through the diet; thus, the term "vitamin" is conditional upon the circumstances and the particular organism. For example, ascorbic acid (one form of vitamin C) is a vitamin for humans, but not for most other animal organisms. Supplementation is important for the treatment of certain health problems, but there is little evidence of nutritional benefit when used by otherwise healthy people. What are vitamins? What vitamins do I need? Vitamins are organic compounds which are needed in small quantities to sustain life.
We need to take vitamins from food because the human body either does not produce enough of them or none at all. Each organism has different vitamin requirements. For example, vitamin C (ascorbic acid) is necessary for humans but not for dogs, because dogs can produce (synthesize) enough for their own needs, while humans cannot. This article explains what vitamins are, what they do, and what foods provide each type. Shop - VITAMIN E: Uses, Side Effects, Interactions and Warnings ... Vitamins: MedlinePlus. Vitamin A - Wikipedia. This article is about the family of vitamers.
For the form usually used as a supplement, see Retinol. Chemical structure of retinol, one of the major forms of vitamin A Vitamin A is a group of unsaturated nutritional organic compounds that includes retinol, retinal, retinoic acid, and several provitamin A carotenoids (most notably beta-carotene). Vitamin A has multiple functions: it is important for growth and development, for the maintenance of the immune system and good vision. Vitamin A is needed by the retina of the eye in the form of retinal, which combines with protein opsin to form rhodopsin, the light-absorbing molecule necessary for both low-light (scotopic vision) and color vision. Vitamin A also functions in a very different role as retinoic acid (an irreversibly oxidized form of retinol), which is an important hormone-like growth factor for epithelial and other cells. Vitamin A can be found in two principal forms in foods: Medical use
Vitamin C - Wikipedia. Vitamin C, also known as ascorbic acid, L-ascorbic acid, and ascorbate, is a vitamin found in food and used as a dietary supplement. As a supplement it is used to treat and prevent scurvy. It may be taken by mouth or used by injection. It is generally well tolerated. Vitamin C was discovered in 1912, isolated in 1928, and first made in 1933. It is on the World Health Organization's List of Essential Medicines, the most important medications needed in a basic health system. The wholesale cost in the developing world is about 0.19 to 0.54 USD per month. Ascorbic acid is also widely used as a food additive, to prevent oxidation.
Medical uses Vitamin C supplements at a drug store. Studies of the potential of vitamin C supplementation to provide health benefits have provided conflicting results. Discount Vitamins & Herbal Supplements from Puritan's Pride. Vitamin A — Health Professional Fact Sheet. Introduction Vitamin A is the name of a group of fat-soluble retinoids, including retinol, retinal, and retinyl esters [1-3].
Vitamin A is involved in immune function, vision, reproduction, and cellular communication [1,4,5]. Vitamin A is critical for vision as an essential component of rhodopsin, a protein that absorbs light in the retinal receptors, and because it supports the normal differentiation and functioning of the conjunctival membranes and cornea [2-4]. Vitamin - definition of vitamin by The Free Dictionary. Vitamín vitamin vitamiin vitamiini vítamín ビタミン.
Nature Made Vitamins, Minerals and Supplements. Vitamins & Supplements Center – Nutritional, Herbal, Dietary, and More. VITAMIN B12: Uses, Side Effects, Interactions and ... Vitamin D - Wikipedia. Vitamin D refers to a group of fat-soluble secosteroids responsible for increasing intestinal absorption of calcium, iron, magnesium, phosphate, and zinc.
In humans, the most important compounds in this group are vitamin D3 (also known as cholecalciferol) and vitamin D2 (ergocalciferol). Cholecalciferol and ergocalciferol can be ingested from the diet and from supplements. Very few foods contain vitamin D; synthesis of vitamin D (specifically cholecalciferol) in the skin is the major natural source of the vitamin.
Dermal synthesis of vitamin D from cholesterol is dependent on sun exposure (specifically UVB radiation). Vitamin D from the diet or dermal synthesis from sunlight is biologically inactive; activation requires enzymatic conversion (hydroxylation) in the liver and kidney. Vitamin A: MedlinePlus Medical Encyclopedia. Vitamin C Benefits, Sources, Supplements, & More. Mark A.
Moyad, MD, MPH, senior research associate and Phil F. Jenkins Director, Complementary and Alternative Medicine, University of Michigan Urology Center. Phyo K. Vitamin D — Health Professional Fact Sheet. Introduction Vitamin D is a fat-soluble vitamin that is naturally present in very few foods, added to others, and available as a dietary supplement.
It is also produced endogenously when ultraviolet rays from sunlight strike the skin and trigger vitamin D synthesis. Niacin - Wikipedia. Niacin, also known as vitamin B3 and nicotinic acid, is an organic compound with the formula C 6H 5NO 2 and, depending on the definition used, one of the 20 to 80 essential human nutrients.
Pharmaceutical and supplemental niacin are primarily used to treat hypercholesterolemia (high cholesterol) and pellagra (niacin deficiency). Insufficient niacin in the diet can cause nausea, skin and mouth lesions, anemia, headaches, and tiredness. The lack of niacin may also be observed in pandemic deficiency disease, which is caused by a lack of five crucial vitamins (niacin, vitamin C, thiamin, vitamin D, and vitamin A) and is usually found in areas of widespread poverty and malnutrition. Niacin has not been found to be useful in decreasing the risk of cardiovascular disease in those already on a statin but appears to be effective in those not taking a statin.