Why would someones hair thin or become loss?

most likely stress

Why would someones hair thin or become loss?

most likely dirty folicules (build up), if it is only loss it may be stress ...lack of vitamins or illness in the worst of the cases.Try changing shampoo for a milder one, If you use conditioner then use it ONLY on the tips, there楹搒 this shampoo Folicure its worked for me you can try it and try fermodyl treatments if you case is only cosmetic.