Why Hair Thins With Age (And What's Actually Reversible)

Hair thinning has several distinct causes, and telling them apart matters because the effective response is different for each one.

Pattern hair loss

Androgenetic alopecia, the most common cause in both men and women, is driven by genetic sensitivity to DHT, a hormone that gradually shrinks hair follicles over successive growth cycles.

Telogen effluvium

A stressful event, illness, or major dietary change can push a large share of hairs into the shedding phase at once. Unlike pattern hair loss, this type is usually temporary and resolves within months once the trigger passes.

Nutrient-related thinning

Iron, protein, and biotin deficiencies can all contribute to thinning, and are worth ruling out with a blood test before assuming the cause is purely genetic.

What has real evidence behind it

For pattern hair loss specifically, topical minoxidil and prescription options have the strongest clinical evidence. For other causes, addressing the underlying trigger is usually more effective than any topical product.