Allergies, asthma and dry eyes could all be irritated by fans which, as well as lowering temperature in room, blows dust and pollen around.
While it is really difficult to sleep on the bed during balmy warm summer nights, having a fan blow air around din the bedroom can actually make one unwell, says study.
Allergies, asthma and dry eyes could all be irritated by the device which, as well as lowering the temperature in the room, is blowing dust and pollen around.
Researchers say keeping a room shaded during the day and drinking cold water instead of caffeine or alcohol can help one keep cool.
People may decide to use the spinning blades to achieve more comfortable temperature for sleeping, create a soothing white noise and freshen the air in the room. However, unwanted effects might include allergic reactions, asthma attacks, dryness, irritated sinuses, and sore muscles.
The fan could blow dust and pollen around the room causing hay fever, allergies or asthma to flare up – which is more likely to keep one awake.
Constantly being blasted with dry air might also cause skin to dry out, as well as eyes and mouths – many people do not sleep with those fully closed.
Also, a stream of cold air could dry out the eyes as well causing major irritation.
Furthermore, the air can dry out people's mouths, throats and noses, which can irritate the sinuses and cause the body to create extra mucous to fight back.
Cool air can also make people's muscle tense up, which could leave them waking up feeling stiff or experiencing cramps.
Researchers recommend shade, drinking water and avoiding alcohol as alternatives to not keeping fans in bedrooms.
They suggest keeping windows and curtains closed, or putting shades or reflective material on the outside of windows.
Cool showers and drinking cold water also help cool down.