As UK households face increasingly hot nights—and with only about 5% equipped with air conditioning—many are relying on electric fans to stay cool. But health expert Dr. Naheed Ali warns that using a fan overnight can come with hidden health risks.

One of the most common issues is dryness. Constant airflow can dry out your throat and sinuses, leading to thicker mucus, congestion, a scratchy voice, or persistent coughing throughout the day.

Another concern is allergies or asthma. Fans circulate dust, dander, pollen, and lint—particles that can trigger sneezing, wheezing, or a tight chest, especially for those with respiratory sensitivities.

Muscle stiffness is also possible. A direct stream of cold air may cause muscles in your neck and shoulders to tighten while you sleep, leaving you sore in the morning.

Despite these risks, there are safe ways to use a fan while sleeping.

First, try setting a timer so the fan turns off about 90 minutes after you fall asleep. This helps cool you initially without prolonged exposure.

Avoid pointing the fan directly at your body. Instead, aim it at a wall or away from your sleeping position to soften the airflow.

Staying hydrated is key—keep water by your bedside to prevent a dry mouth or throat.

Lastly, reduce allergens in the room. Wash bedding weekly and clean or replace air filters regularly to improve air quality.

With a few simple adjustments, you can enjoy a cooler night’s sleep without sacrificing your health.