Sleeping naked during a heatwave sounds like common sense, but experts warn it might make you even hotter—not cooler—by trapping sweat instead of letting it evaporate. So next time a tropical night hits, pajamas might actually save your sleep.

Surprisingly, experts say sleeping naked in a heatwave can make you hotter because without breathable fabric, trapped sweat stays on your skin, impeding natural cooling. That’s why heatwave pros recommend light cotton pajamas—they wick away moisture and keep you cooler.