Biochemically this vitamin is involved in one reaction by which pyruvic acid (derived from glucose as described above) is further metabolised. It is also required for fatty acid synthesis. The most commonly recommended allowance is 150-300mcg per day. Like other B Vitamins, biotin is recommended for several conditions, like skin troubles, muscle pains, depression and baldness. These connections are probably superficial and non-specific. Biotin has been found, however, to encourage improvements to the composition of the bowel flora and many of its beneficial effects upon the rest of the body could well be mediated through this route. Action that can be suggested for supplementation is as follows. For all subjects, supplementation can be to the level of 40mcg per day, so that the supplements make some significant contribution to intake. Apart from that, steps should be taken to improve the quality of the bowel flora, which can then synthesise biotin, so that supply from that source is enhanced. In subjects for whom a special effort is being made to improve the bowel flora by use of a strong powdered bowel flora products, extra biotin supplementation at the level of 1000mcg per day may be advised by practitioners. >>Source

Uses in the body: needed for healthy skin, hair, nerves and bone marrow. Also helps to metabolise carbohydrate and protein to provide energy. Is absorbed from food and also produced by bacteria in the intestines.

Signs of deficiency: weakness, fatigue, skin irritation, cradle cap in babies, hair loss, poor appetite, depression. Long-term antibiotic use can cause biotin deficiency, as can consuming too much raw egg white.

Therapeutic uses: skin, nail and hair problems, including alopecia. An important nutrient for people on iron supplements, as the two nutrients are closely linked, and for those taking antibiotics or other medicines which can affect biotin production in the intestines. Athletes may benefit as they’re often deficient in this nutrient.

Dietary sources: wholegrains (wholemeal bread, brown rice, bran cereals), egg yolk, nuts, beans, peas, cauliflower, liver, kidney, fish.

Recommended daily allowance: 150µg
Typical therapeutic daily dose: 500µg to 1,500µg
Daily intake shouldn’t exceed: 2,500µg

Cautions: no contraindications, but keep to recommended dosage.

Best taken: with food at breakfast and lunch/dinner for split dose.