Vitamins are classified as either water-soluble or fat-soluble. In humans there are 13 vitamins: 4 fat-soluble (A, D, E, and K) and 9 water-soluble (8 B vitamins and vitamin C). Water-soluble vitamins dissolve easily in water

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Anti-vitamins are chemical compounds that inhibit the absorption or actions of vitamins. For example, avidinis a protein in raw egg whites that

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

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Sources
For the most part, vitamins are obtained from the diet, but some are acquired by other means: for example, microorganisms in the

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In those who are otherwise healthy, there is little evidence that supplements have any benefits with respect to cancer or heart disease.

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The reason that the set of vitamins skips directly from E to K is that the vitamins corresponding to letters F–J were either reclassified over time,

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In setting human nutrient guidelines, government organizations do not necessarily agree on amounts needed to avoid deficiency or maximum amounts to avoid the risk of toxicity. For example, for vitamin C, recommended intakes range from 40 mg/day in India to

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