There is no recommended dietary allowance for biotin. Claims of biotin supplements being effective in treating hair loss have not been proven. More »

While he acknowledges that the role biotin plays in hair growth is unclear, dermatologist Dr. Richard Scher claims that this vitamin does improve keratin infrastructure. He also acknowledges that biotin supplements may h... More »

Biotin deficiency has been linked to both hair loss and brittle nails; the B-vitamin is a natural remedy for each condition, according to FITDAY vitamin and mineral experts. Biotin also supports the health of the skin, n... More » Health Medications & Vitamins

While there is no recommended dietary allowance for biotin, an adequate dosage for adults 18 years of age and older is 30 micrograms daily. The appropriate dose is ultimately subject to the age, health and needs of the p... More »

As a dietary supplement, the U.S. recommended daily allowance of vitamin B-1, or thiamine, is 1.2 milligrams for males 14 years and older and 1.1 milligrams for women over 18 years old, according to MedlinePlus. In speci... More » Health Medications & Vitamins Vitamins & Supplements

The adequate intake of biotin depends on the age of the person taking the supplement and varies from 5 to 35 micrograms per day, reports WebMD. However, the need to supplement this nutrient is uncommon because it is rare... More »

The recommended dietary allowance (RDA) of magnesium a person should take depends on factors like sex and age; for example, adult males over 30 need about 420 milligrams per day, while adult females over 30 require abou... More » Health Medications & Vitamins Vitamins & Supplements