Your fan could actually be making your home hotter

I'm the person who sleeps with the air conditioning and the fan on. And while growing up, my mom used to lecture me for my "waste" of electricity (which, to be fair, I understand now that I pay my own energy bill), I may have been on to something.

That's because a new study in the Annals of Internal Medicine found that using an electric fan on its own may not only not cool you down, it might make you (and your home) even hotter. Here's what you need to know about when—and when not—to use your fan, plus other tricks for staying cool in the summer heat.

Why fans don't always cool you down

According to the study, during which people sat in hot conditions for two hours, the majority of the people who used a fan the whole time actually felt worse than those without a fan (especially those in dry heat vs. humid). That's because fans just circulate air—they don't cool it. So when the air temperature is higher than your own body temperature (98.6 degrees), they can end up making you hotter.

One of our senior writers, Mark Brezinski, explains, "Fans speed up your rate of dehydration and electrolyte imbalance. They also speed up the rate of 'heat-attributable conditions' like heat exhaustion, so when it's very hot out you should mainly use your fans to either exhaust heat from the room or pull in cooler air."

When should I use a fan vs. the air conditioning?

But just because your electric fan isn't a one-size-fits-all solution to beating the heat, that doesn't mean it doesn't have its place. Opting to turn on a fan instead of your air conditioning can save you a lot money, for instance, and have the placebo effect of making you feel cool (even if it really isn't).

"It's ideal to use a fan when it's below 90°F, per the CDC, primarily because they use about 100x less energy than traditional air conditioners," Mark recommends, adding that "anything above 90°F is AC territory."

How to stay cool without a fan

Number one: Keep your body temperature down by drinking plenty of cold water or holding ice packs on pressure points like your wrist, neck, or temples. Then, cool down your house by shutting blinds or curtains during the day to keep the hot sun out (blackout shades are ideal!) and avoiding using the stove or oven as much as possible.

And if you're struggling to sleep because of the heat, consider changing up your bedding. Choose lightweight sheets in natural fabrics like linen or cotton that are more breathable and use a cooling bamboo pillow.