Side Effects of Sleeping with a Fan On

Written by Jill Zwarensteyn, Senior Editor

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In This Article

Are there side effects of sleeping with a fan on? We explore the research on this.

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For some people, having a ceiling or floor fan in their bedroom helps them fall asleep and stay cool at night. If you’re in a hot or closed-off room, the thought of sleeping without one can seem unbearable, and for those of you with noisy neighbors (been there!), the humming can help drown out music and other sounds.

But are there downsides to using a fan at night? We’ll cover the potential side effects of falling asleep with a fan on.

Why Use a Fan While Sleeping?

Sleeping with a fan on can be beneficial for certain people and situations. The reasons why someone might use a fan at night can vary, but the goal is usually the same: better sleep.

We talked with Dr. Kiran Dintyala, who grew up in India, and said that fans were an inseparable part of his family’s sleeping routine. “I had the soundest sleep of my life during those 25 years in India,” Dr. Dintyala said. 

White Noise

The sound a fan makes is similar to white noise. People are attracted to the idea of white noise to help with sleep because it drowns out background noises and dulls jarring sounds like car alarms, a snoring partner, yelling neighbors, slamming doors, and sirens.¹ In some cases, people may have difficulty sleeping in complete silence and may feel more at ease with white noise from a fan.

When he was younger, Dr. Dintyala didn’t know the term “white noise”; he just knew he couldn’t sleep without a fan. The hum of his fan drowned out the late-night city noises. “Rumbling trucks and honking taxis created an auditory nightmare, but the white noise from the fan masked those extraneous sounds and created a soothing, peaceful feeling. Now, it’s scientifically proven that white noise helps people sleep better at night.”

Cooling

Fans are a low-cost way to cool a warm room. While they won’t keep you as cool as an air conditioner, we found a way to turn a basic fan into a makeshift air conditioning unit. Here’s how:

• Get a few bottles of water, about four to six.
• Add two to three tablespoons of salt to each bottle.
• Put the bottles in the freezer.
• When you’re ready for bed, put the frozen bottles on a tray. The tray is there to collect condensation and prevent a watery, leaky mess.
• Put the tray of frozen bottles in front of your fan.
• Turn it on. As the air blows by the frozen water, you’ll feel a cool breeze.

View Our Guide: Best Cooling Mattresses

Air Circulation

Another benefit of a fan is air circulation. A closed-off room can feel stuffy and in some cases, may start to smell bad as a result. By circulating air with a fan, you boost the room’s freshness.

Side Effects of Sleeping with a Fan

Despite the advantages, you may need to avoid sleeping with a fan on for specific health and environmental reasons. If you experience a negative side effect like these, you should discontinue using a fan immediately.

Allergic Reactions

Despite the advantages of using a fan, you may need to avoid sleeping with a fan on for specific health and environmental reasons. If you experience a negative side effect like these, you should discontinue using a fan immediately.

Also, take a close look at your fan. If it’s been collecting dust on the blades, those particles are flying through the air every time you turn it on.

Check out our picks for the best mattresses for allergies.

Dry Air

Fans can dry out the air around you.² Breathing in dry air can cause unwanted side effects such as asthma, bronchitis, sinusitis, nosebleeds, and dehydration.³ A steady dry stream of air can also dry out your eyes, and for those who sleep with their mouth open, the dry air could also lead to a sore throat.^{2, 4}

According to Dr. Dintyala, you can combat some of the issues caused by fans drying out the air by keeping the fan from blowing directly on your face, adding that oscillating fans can help as they move air around the room. He also recommends using a humidifier to add moisture to the air. 

Sore Muscles and Joints

People who sleep with a breeze directly on them may wake up with stiff or sore muscles. This is because the cool air can make muscles and joints feel stiff and sometimes painful.⁵ If you’ve been waking up with a stiff neck in the morning, it might be because of the constant breeze.

“You may experience some muscle aches if you’re exposed to cold air all night.” – Dr. Kiran Dintyala