Turn down the thermostat to 65 °F (18.3 °C) to fall asleep easier, and sleep better, says the science about sleep. The body’s core temperature actually needs to drop by 2 or 3 °F to initiate sleep. And what I suspect many of us in warmer climates know : the body tries to lose heat through the hand and feet, so stick one or two out from under the blanket if the room temperature is a little too high.