Hi....., vitamin B-12 deficiency or problems with your pituitary or thyroid gland can cause hair loss that’s reversible if the problem is corrected, .... Although you can't reverse natural balding, you can protect hair from damage that may eventually lead to thinning..... To prevent hair damage that may cause hair loss, follow these tips: Go natural: Leave your hair its natural color and texture.....consult Dermatologist.....