It is thought that sunlight can be both good and bad for people with vitiligo, for several different reasons.
For example, on the disadvantage side, some medical experts believe it’s possible that sunburn could be a trigger for developing the skin condition. Moreover, people with vitiligo lack melanin, which is the body’s natural protection from the sun, so sun exposure can be particularly dangerous. That’s why it’s vital that people with vitiligo use broad-spectrum sun protection with an SPF (sun protection factor) of 30 and above.
On the other hand, controlled exposure to ultraviolet rays through light therapy is sometimes prescribed as treatment for vitiligo that is more widespread, usually in combination with medication. This treatment is called PUVA, which is a combination of the medication psoralen (P) and long-wave ultraviolet radiation (UVA). It was initially developed as a treatment for psoriasis.