Can biotin cause hair growth on face? While data on beard growth in particular is limited, several studies suggest that biotin supplements can improve hair thickness in people with conditions affecting hair growth, such as alopecia, though beard hair is not specifically mentioned ( 1 , 5 ).
What can speed up facial hair growth? Beard growth tips
Does biotin cause unwanted hair growth? Still, biotin supplements are only likely to prevent hair loss and promote hair growth in people with a biotin deficiency. In one study, a biotin deficiency was found in 38% of women complaining of hair loss.