What does "broad spectrum" mean on a sunscreen label?

Broad spectrum means the sunscreen protects against both UVB rays (which burn your skin) and UVA rays (which age it and cause deeper damage). The FDA requires a specific test for that label, so if it says “broad spectrum SPF 30,” the SPF 30 covers UVB and the UVA protection meets a threshold. Avoid sunscreens that only mention SPF without “broad spectrum”—they likely lack UVA protection.