Cool showers and cutting back on coffee and alcohol might be the key: climate change is impacting sleep quality. Scientists are now looking for ways to help us adapt to these rising temperatures.
The human brain is quite sensitive to heat; when temperatures rise, our internal thermostat and stress responses kick in.
Researchers are diving into how our bodies can cope with higher temperatures, which can disrupt sleep and lead to various health issues.
A review in the Journal of Sleep Medicine in 2024 emphasized that climate change and urbanization present significant threats to health, performance, and overall well-being.
According to a 2022 survey published in One Earth, people lost about 44 hours of sleep on average each year during the first two decades of the 21st century.
If global warming continues, studies suggest that we could lose between 50 to 58 hours of sleep annually per person by 2099, according to research led by Kelton Minor from the University of Copenhagen.
There’s an urgent need for interventions to protect the crucial balancing act that sleep provides in increasingly warmer conditions, say the researchers involved.
The brain’s neurons that manage sleep and temperature are closely linked, and lowering the body’s internal temperature is essential for better sleep quality.
Fabian Sovet from the University of Kite in Paris notes that while our bodies have adaptive abilities, there are costs. For instance, we may sweat more but also require more hydration, which has its limits. So, during heat waves, altering behaviors—like activities and clothing—becomes really important.
Interestingly, Sovet points out that humans can tolerate higher temperatures than many think; studies indicate that good sleep can occur even at room temperatures nearing 28 degrees Celsius (82.4 degrees Fahrenheit).
He challenges the common belief that bedrooms should be kept at 18-20°C, suggesting that wearing lighter clothing and ensuring good ventilation could help manage heat better.
“If we keep relying on air conditioning, we won’t adapt at all,” he remarked.
Confronting Sleep Disruption
Armelle Rancillac, a neuroscientist at the Center for Interdisciplinary Research in Biology, stated that anything above 28°C complicates sleep even further.
Insufficient sleep can hinder the body’s recovery processes. In the short term, it may lead to increased drowsiness, fatigue, and accidents, whether at work or on the road.
Long-term sleep deprivation can contribute to sleep “debt,” interfere with metabolism, and elevate risks for issues such as weight gain, diabetes, cardiovascular diseases, and even neurodegenerative conditions like Alzheimer’s.
Moreover, lack of sleep can diminish stress resilience and negatively affect mental health.
To improve sleep in hotter conditions, Rancillac stresses the importance of managing “sleep enemies.”
Taking a cold shower before bed is advised, along with reducing caffeine and alcohol intake. Also, post-exercise hot tubs should be avoided in favor of cooler baths or outdoor temperatures, according to Sovet.
Napping during the hottest parts of the day can alleviate sleep deprivation effects—ideally, a short nap of 30-40 minutes before 2 PM is recommended.
