Why you should ditch the electric fan during a heatwave

Masterfile

You’re lying in bed — too hot to sleep, too hot for blankets, so hot even the top sheet on your bed feels like a flannel blanket against your boiling skin. Ah, the sorrows of a summer heat wave and its far-too familiar nocturnal ritual of discomfort and bouts of irrational rage.

Desperate for some relief, you crank the electric fan to its highest level and draw it closer. The blades whirr, spinning dust around the room. That fan is really working hard! So why are you still so hot?

Well, if a recent review of studies on the effectiveness of electric fans by public health experts in the U.K. proves accurate, it’s because fans don’t appear to be that useful when it comes to cooling the air, especially when temperatures outside are soaring.

What do fans do other than make a lot of noise then? The experts argue that fans may do more harm than good. In some cases of extreme weather, they can increase your body temperature as they blow hot air on you, which may increase the chance of dehydration if you’re not conscious of drinking fluids.

As Time writer Alexandra Sifferlin points out, this potential drawback of relying on fans solely in times of extreme heat has increased significance for the very young and the very old, two groups that are particularly susceptible to heat exhaustion. Moreover it has implications for how public health departments respond to community need during scalding summer temperatures.

Health Canada advises people not to use a fan in a hot room without windows during a heat wave but instead advises people find air-conditioned spaces to find relief.

Other things you can do to beat the heat: take intermittent cold showers, avoid physical activity and drink lots of water.    

How do you cool down in the hot summer months?