Why is my hair falling out?

Health Magazine has listed the following reasons for hair loss:  PHYSICAL STRESS (surgery car accident  even the flu can cause hair loss)   PREGNANCY    Too much of VITAMIN A is a reversible cause of hair loss.  Once excess VITAMIN A is halted, hair should grow normally.  LACK OF PROTEIN (This will start to happen 2 to 3 months after the drop in protein intake.)    MALE PATTERN BALDNESS    FEMALE PATTERN BALDNESS (Both are hereditary)   FEMALE HORMONES (Birth control pills)   ANEMIA   HYPOTHYROIDISM    VITAMIN B DEFICIENCY    OVERACTIVE IMMUNE SYSTEM   LUPUS   DRAMATIC WEIGHT LOSS    CHEMOTHERAPY   POLYCYSTIC OVARY SYNDROME   OVERSTYLING   IMPULSE CONTROL DISORDER (compulsively pulling your hair out)   AGING   ANABOLIC STEROIDS                  MEDICATIONS:  ANTI-DEPRESSANTS   BLOOD THINNERS     BLOOD PRESSURE MEDS   IBUPROFEN