Health

Biotin, otherwise known as vitamin B7 or vitamin H, is an unofficial member of the B family. It is found in trace amounts in all living tissue, both animal and plant. However, it is also manufactured by friendly bacteria in the intestine, so this is one of the few vitamins that does not necessarily need to be consumed.

Natural Food Sources
American cheese, banana, brewer's yeast, brown rice, bulgur wheat, butter, cauliflower, clams, egg yolk, liver, legumes, mushrooms, nuts, oatmeal, salmon, wheat germ.

Main Functions
Biotin is involved in the metabolism of fatty acids. It helps release energy from carbohydrates and amino acids. It is necessary for healthy skin, hair, nails, blood cells, nerve tissue, bone marrow and sweat glands, plus it may help prevent depression.

Deficiency Symptoms
Deficiencies are rare, but can occur if too many antibiotics are taken or too many raw egg whites are consumed. Symptoms include anemia, skin problems, hair loss, muscle pain, fatigue, insomnia, nausea and high cholesterol.

Toxicity Symptoms
Overdose is unlikely. Supplements contain nontoxic amounts.

Dietary Reference Intake
Because the body manufactures biotin, no official Dietary Reference Intake or Recommended Dietary Allowance has been set for this vitamin. However, as a guideline, adults need about 30 mcg of biotin daily.