Sunburn Math: How Many Burns Until It's Dangerous?

Risk rises with cumulative burns: research links five or more sunburns to roughly double the risk of melanoma, and even one blistering sunburn in childhood or adolescence more than doubles lifetime risk. Preventing burns at every age meaningfully lowers risk.

Yes. People with darker skin get skin cancer less often but are frequently diagnosed later, when it's harder to treat — and melanoma can appear in less sun-exposed areas like the palms, soles and under the nails. Everyone, regardless of skin tone, should use sun protection and watch for changes.

Evidence indicates yes. In the landmark Australian Nambour trial, adults using sunscreen daily had fewer melanomas — with a statistically significant reduction in invasive melanoma — than those using it at their discretion. Regular broad-spectrum use, alongside shade and clothing, lowers skin-cancer risk.