Sunburn and Unprotected UV Exposure
Ultraviolet radiation is one of the most documented accelerants of vitiligo. When UV rays damage skin cells in someone already living with the condition, the immune system's attack on melanocytes intensifies at the site of injury. This is called the Koebner phenomenon, new depigmentation appearing precisely where the skin has been traumatised. A 2017 study published in the Journal of the European Academy of Dermatology and Venereology found that Koebner responses occurred in roughly 50% of vitiligo patients, with sun damage among the most common triggers. In India, where outdoor exposure is unavoidable and SPF habits remain inconsistent, this is a real and underestimated risk. Broad-spectrum SPF 50 applied daily to depigmented patches is not optional, those patches have no melanin to absorb UV and burn faster than surrounding skin.
