I am 23 and have been having hair loss beginning when I was 19. Up until the hair loss began, my hair was always very thick/poofy. My grandmother had thick hair, even into her 70's. I never would have guessed that thin hair would be a problem for me. My hair now looks thin/stringy and I fear it getting worse. I have not found a cause for this yet. Every doctor I go to tells me I am normal in vitamin levels and don't test for any diseases.