1. Telogen effluvium
Telogen effluvium is a phenomenon that occurs after pregnancy, major surgery, drastic weight loss, or extreme stress, in which you shed large amounts of hair every day, usually when shampooing, styling, or brushing. It can also be a side effect of certain medications, such as antidepressants, beta-blockers, and nonsteroidal anti-inflammatory drugs. During telogen effluvium, hair shifts faster than normal from its growing phase into the "resting" phase before moving quickly into the shedding, or telogen, phase.
2. Hereditary hair loss
Hair loss that is genetic is known as androgenetic alopecia and, according to the American Academy of Dermatology, is the most common cause of hair loss. The gene can be inherited from either your mother's or father's side of the family, though you're more likely to have it if both of your parents had hair loss.
Hypothyroidism
4. Lupus
Lupus is a chronic autoimmune disease in which the body’s own immune system attacks healthy tissues. The condition affects about 1.5 million people and tends to strike women during their childbearing years.
5. Iron deficiency anemia
Women who have heavy periods or don’t eat enough iron-rich foods may be prone to iron deficiency, in which the blood doesn’t have enough red blood cells. Red blood cells transport oxygen to cells throughout your body, giving you the energy you need.
6. Polycystic ovarian syndrome
As many as five million women in the United States suffer from polycystic ovarian syndrome. The condition, which can begin as early as age 11, is caused by a hormonal imbalance in which the ovaries produce too many male hormones. PCOS often causes infertility.
7. Skin conditions of the scalp
An unhealthy scalp can cause inflammation that makes it difficult for hair to grow. Skin conditions that lead to hair loss include seborrheic dermatitis (dandruff), psoriasis, and fungal infections such as ringworm.
8. Alopecia areata
Alopecia areata is an autoimmune disorder in which the immune system attacks hair follicles. It affects about 4.7 million people in the United States and occurs equally in men and women. The cause is unknown, but it may be triggered by stress or illness.
9. Excessive styling
Too much shampooing, styling, and dyeing can harm your tresses. Heat and chemicals weaken the hair, causing it to break and fall out. Often, it’s a combination of treatments—keratin, coloring, and blow-drying, for instance—that does the damage
