What are vitamins?

Deborah Beauvais
Nutrition & Dietetics
Vitamins are substances which, in small amounts, are necessary to sustain life. They must be obtained from food as they are either not made in the body at all, or are not made in sufficient quantities for growth, vitality and well-being. A deficiency of a particular vitamin causes disease symptoms which can only be cured by that vitamin.

Vitamins are chemically unrelated substances and all are organic. Organic substances are those that contain carbon and come from materials that are living, such as plants and animals, or that were once living, for example petroleum or coal.

It is impossible to sustain life without all the essential vitamins.
Vitamins (and minerals too) are substances in food that are essential to the normal growth, development and functioning of the body. Your body needs 13 vitamins to stay healthy:
  • Fat-soluble vitamins (A, D, E and K) are absorbed by and stored in the body for up to several months.
  • Water-soluble vitamins dissolve in body fluids. If they're not used, they’re excreted in urine. These are vitamin C and all of the B vitamins -- B1 (thiamine), B2 (riboflavin), B3 (niacin), B5 (pantothenic acid), B6, B7 (biotin), B12 and folate/folic acid.
Not getting enough of any particular vitamin may cause certain deficiency diseases. For example, too little B6 or B12 may cause anemia. Too little vitamin D may lead to rickets (a weak-bone disease) in children.

Too much of any vitamin can also cause problems. Excess vitamin B6, for example, may trigger symptoms such as nerve damage and trouble walking. Too much vitamin D may lead to heart arrhythmias. Talk to your doctor about whether you’re getting enough vitamins from the foods you eat and whether you may need to take vitamin supplements and, if so, the best dosages for you.
Michael T. Murray, ND
Naturopathic Medicine

Vitamins are essential nutrients required for normal chemical processes to occur in the body. They serve as essential components in enzymes and coenzymes. Most enzymes are composed of a protein along with an essential mineral, and possibly a vitamin. If an enzyme is lacking the essential mineral or vitamin, it cannot function properly.

Encyclopedia of Healing Foods

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Encyclopedia of Healing Foods

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.