Seeing a clump of hair on your hairbrush or in the shower can be a scary thing, and there are so many potential causes of thinning hair that searching for a solution can be stressful. One of the contributors — and perhaps a surprising one — is dandruff. It’s common, too, so if you have it, know you’re far from alone. “I’ve been treating scalp and hair conditions for more than 25 years, and dandruff is one of the most common issues I see,” said Dr. Paul Farrant , a consultant dermatologist and