At 18, my hair has begun to fall out rapidly. i am considering biotin (b7) to help. are there any risks or permanent side effects to b7 supplements?

Perfectly safe: Biotin is a very safe nutrient with no known toxicity. It sometimes helps with hair loss, but not always. There could be other causes, such as thyroid imbalances, that will not be addressed by biotin, so if biotin does not help it would be wise to be evaluated by a doctor, preferably a holistic doctor who knows about herbs and supplements- see http://www.Abihm.Org/search-doctors.

See your doctor: Hair loss may occur for many different reasons, the most significant of which is hypothyroidism. So you need an general evaluation. Biotin deficiency is extremely rare - it is found in many common foods and actually produced by bowel bacteria. There is no evidence that increased levels of biotin provide any health benefit.