How to keep cool in a heatwave: should you really drink tea and sleep naked when it’s hot?

“It’s natural on a hot day to keep all your windows and doors open,” says Dr Alannah Hare, an NHS and private sleep consultant at the Royal Brompton. “However, the best thing to do is to keep your windows shut and your curtains drawn all day. It’s all due to temperature differentials. When you open your windows in the morning it feels cool and lovely, but as the sun comes up throughout the day it heats the inside of your house.