What causes hair loss?

Male- and female-pattern hair loss (genetic)

The most common cause by a wide margin. Androgenetic alopecia is driven by genetics and the hormone DHT, which slowly shrinks follicles. Men get a receding hairline and crown thinning; women get diffuse thinning along the part. It's progressive, so treating it sooner keeps more hair. See the proven treatments.

Telogen effluvium (stress shedding)

A temporary, heavy shed that appears a few months after a shock — heavy stress, illness, surgery, childbirth, or rapid weight loss. It generally clears on its own once the trigger passes.

Thyroid and hormonal changes

An under- or over-active thyroid, pregnancy, menopause, or coming off birth control can all prompt shedding. A blood test is worthwhile, since fixing the underlying issue often restores the hair.

Nutritional gaps

Low iron (ferritin), vitamin D, zinc, or protein can thin hair — crash diets are a frequent trigger. Correcting the shortfall usually helps.

Medications

Blood thinners, some antidepressants, beta-blockers, retinoids, and chemotherapy can all cause hair loss. Never stop a prescribed medication without checking with your doctor first.

Alopecia areata (autoimmune)

Here the immune system attacks the follicles, leaving round, patchy bald spots. It's separate from pattern loss and needs a dermatologist's diagnosis and treatment.

Traction alopecia

Caused by tight styles — buns, braids, extensions, ponytails — tugging on follicles over time. Caught early it reverses; long-term tension can scar and permanently damage follicles.

Scalp conditions

Fungal infections (ringworm), severe seborrheic dermatitis, or psoriasis can cause shedding or breakage. Treating the scalp condition clears the loss.

Aging

Separate from pattern baldness, hair naturally thins and grows more slowly with age as follicles wind down.

Which cause is it?

Genetic loss is gradual and follows a set shape; sudden or patchy loss usually signals something else. If you're unsure — or the shedding is fast, patchy, or comes with other symptoms — see a Tulsa clinic or dermatologist to identify the cause before starting treatment. For genetic thinning, the proven treatments and a transplant are the main routes.