Same here. I cannot take Biotin. Which is sad, because I hear it does wonderful things. After an injury my hair pretty much completely stopped growing for about 2 years. When my body was finally healed enough to spend some energy on hair growth it was still super slow. My annual blood work came back fine, but I read that a lot of people, especially Americans, are iodine deficient. So I started taking one kelp a day, and the change in my hair was amazing! It started growing crazy fast, and the amount that would fall out on a daily basis and when I brush it drastically reduced.