Can high SPF sunscreen trick you into staying out too long?

Yes. SPF 100 blocks about 99% of UVB rays versus 98% for SPF 50, but the 1% difference makes people feel invincible. They skip reapplying, use less, or stay out longer, which leads to burns. Most people apply half the recommended amount, so even SPF 100 effectively becomes SPF 30 or worse. Treat high SPF exactly like SPF 50: apply generously, reapply every two hours, and don’t rely on the number for extra protection.