With hot weather scorching the UK this week, many Brits are looking for ways to stay cool through the night. Leaving a fan on while you sleep can prove costly, so picking the right pajamas is essential. However, a doctor specialising in physiology has busted the myth that sleeping in little to no clothing cools you down. In fact, he revealed that wearing more clothes can actually keep you cooler.

Dr Gareth Nye, lecturer in biomedical science at the University of Salford, said wearing less clothing can trap heat. He explained: “When you sleep without clothes, the sweat you naturally produce stays on the skin. Unless that sweat is evaporated, the heat will remain on the skin — essentially keeping you from cooling down.”

Wearing a specific type of night clothing is actually the best option during hot summer nights because it supports our personal circadian rhythm, according to Dr Nye, who is also the Theme Lead for Endocrinology at the Physiological Society. 

The natural hormone cycle influences our body temperature to drop as we approach bedtime, and rise around two hours before waking, but sleeping without clothes doesn’t account for the shift. 

He explained: “Wearing clothes which closely maintain the natural cycle will help your sleep at night, which is why thin, breathable materials are beneficial.”

However, it doesn’t include all types of pyjamas, as he explained, “anything you wear will potentially disrupt airflow to the skin, impact your skin’s temperature sensors, and increase sweating”.

Phoebe Street, Brand Marketing Manager at Pretty You London, explained which type of fabric is best in warmer weather. 

“Breathable fabrics help the body release excess heat and moisture-wicking materials keep you feeling dry and comfortable through the night.

“That’s particularly helpful for anyone who tends to overheat or experiences night sweats or hot flushes. Natural fabrics that are soft on the skin can really help prevent overheating, irritation and discomfort.

“It’s not just about feeling cool when you get into bed – it’s about staying comfortable as your body temperature naturally changes overnight.”