Japanese hair experts warn UV exposure damages scalp and hair, causing premature greying and loss

Hair and scalp specialists in Japan say that ultraviolet (UV) radiation damages both the hair shaft and the living cells of the scalp. According to hair‑diagnostic expert Nami Ikuma, the damage from sun exposure can be comparable to a single hair‑coloring session, breaking down the protective cuticle and causing the “sun‑bleach” effect that leaves hair dull, brittle and discoloured. The scalp, which receives up to three times more UV than the face, suffers “photo‑aging” that can accelerate the appearance of white hairs, thinning and hair loss months later.

Ikuma recommends physical protection such as wide‑brimmed hats, breathable headwear, and UV‑blocking umbrellas, combined with regular use of hair‑specific UV sprays or oils. She also advises changing the parting position, avoiding prolonged exposure during early summer, and applying scalp moisturisers and cooling treatments if sunburn occurs. Early summer care, she says, can prevent the “3‑month lag” that makes many people notice increased shedding in autumn.

The articles stress that once hair or scalp is sun‑damaged it cannot fully recover, so preventive measures before exposure are essential for preserving hair health over the coming years.