UV Damage of the Hair

The document reviewed the effects of UV damage on hair, highlighting that excessive sun exposure was a primary cause of structural impairment to the hair shaft. Photochemical damage included the degradation of hair proteins and pigments, with UVB radiation causing protein loss and UVA radiation leading to color changes. Free radicals, produced by the absorption of radiation in photosensitive amino acids, adversely affected hair proteins, particularly keratin. Melanin played a protective role by immobilizing free radicals and filtering UV radiation. The review emphasized the importance of protecting the hair cuticle to maintain hair shaft integrity, suggesting the use of hair care products with UV filters as a preventive measure.