A natural part of aging for both women and men is some natural hair loss. And there has been much focus on how biotin promotes hair growth, among many other hair regrowth facts and fallacies. Does biotin really promote hair growth? Scientists are still debating how it helps but if you are experiencing hair thinning or hair loss, you may want to try an increased use of biotin. Biotin is a B vitamin and is sometimes called vitamin H. Important for hair regrowth, this substance has been proven to increase hair growth and decrease loss. It can also lead to a healthier head of thick and shiny hair.