There isn't much evidence to support using biotin alone to promote hair development, although there is some data to support avoiding hair loss.
However, biotin insufficiency is the only condition in which biotin supplements are expected to stop hair loss and encourage hair growth.
In one study, 38% of women who reported having hair loss also had a biotin deficit. A history of deficient risk factors, such as inflammatory bowel disease (IBD) or usage of certain drugs such antibiotics, was present in 11% of these subjects.
This study shows a connection between low levels of biotin and hair loss, even though it did not evaluate the impact of biotin supplements or hair products containing biotin on preventing hair loss.
Additional factors that contribute to hair loss include
Female pattern baldness, or androgenetic alopecia, is characterized by rapid weight loss, iron, zinc, or protein shortages, and certain hormonal disorders, such as thyroid illness.
Because there are many variables that contribute to hair loss and thinning hair, taking biotin supplements without first figuring out what's causing the problem may hinder or postpone the necessary therapy in cases where a biotin deficiency isn't the problem.
It's not always the case that biotin deficiencies stop hair loss, even in those situations where biotin supplements are taken.
For instance, after gastric sleeve surgery, researchers in one study gave a biotin supplement to 22 patients who had low biotin levels due to hair loss
Five of the patients reported a considerable decrease in hair loss after three months, fourteen reported a minor effect, and three reported no effect at all, suggesting that additional factors might potentially be involved in hair loss and how to avoid it.
SUMMARY Since a biotin shortage has been linked to hair loss in certain cases, treating a deficiency with supplements can stop hair loss in certain individuals. Nevertheless, a number of other reasons may also result in hair loss.