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Vitamins

Vitamins are certain chemicals the body needs in small amounts to function properly. They work in a variety of ways, mostly as "helpers"; for example, many of the B vitamins help the body use protein, carbohydrate, and fats.

Vitamins are divided into two categories:

  • Water-soluble vitamins include all the B vitamins and vitamin C. Water-soluble vitamins travel freely through the body, and the part that the body doesn't use passes through the kidneys and leaves the body as urine or stool. The body needs water-soluble vitamins in frequent, small doses, and they are unlikely to reach toxic levels.
  • Fat-soluble vitamins include vitamins A, D, E, and K. Fat-soluble vitamins are stored in the body's cells and are not passed out of the body as easily as water-soluble vitamins. They do not need to be taken in as frequently as water-soluble vitamins (although adequate amounts are needed). And they are more likely to reach toxic levels if a person takes in too much.

ByHealthwise Staff
Primary Medical ReviewerJohn Pope, MD - Pediatrics
Specialist Medical ReviewerRhonda O'Brien, MS, RD, CDE - Certified Diabetes Educator
Last RevisedAugust 29, 2011

WebMD Medical Reference from Healthwise

Last Updated: August 29, 2011
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.