What are vitamins made of?

Vitamins are organic compounds that the body needs in small amounts but cannot synthesize by itself and must obtain through the diet.

Many vitamins consist of a number of compounds called "vitamers" that can be converted to the active form of the vitamin.

There are 13 known vitamins. They are classified by their biological and chemical activity, not their structure.

Five contain only C, H, and O; four contain C, H, O, and N; two contain C, H, O, N, and S; one contains C, H, O, N, S, and Cl; one contains C, H, O, N, P, and Co.

The 13 vitamins are:

• Vitamin A (retinal, C₂₀H₂₈O) —night vision

• Vitamin B₁(thiamine, C₁₂H₁₇ClN₄OS) — beri beri

• Vitamin B₂ (riboflavin, C₁₇H₂₀N₄O₆) —sore throat, lesions of lips and mouth
• Vitamin B₃(niacin, C₆H₅NO₂) — pellagra
• Vitamin B₅ (pantothenic acid, C₉H₁₇NO₅) —tickling, prickling, burning sensations
• Vitamin B₆ (pyridoxine, C₈H₁₁NO₃) — anemia, peripheral neuropathy
• Vitamin B₇ (biotin, C₁₀H₁₆N₂O₃S) — rashes, hair loss, anemia
• Vitamin B₉ (folic acid, C₁₉H₁₉N₇O6₆) — anemia, birth defects

• Vitamin B₁₂ (cyanocobalamin, C₆₃H₈₉CoN₁₄O₁₄P) — anemia

• Vitamin C (ascorbic acid, C₆H₈O₆) — scurvy

• Vitamin D (cholecalciferol, C₂₇H₄₄O) — rickets

• Vitamin E (tocopherol, C₂₉H₅₀O₂) — anemia, poor nerve conduction

• Vitamin K (phylloquinone, C₃₁H₄₆O₂) — bleeding