You're losing 56 hours of sleep per year as the Earth heats up, new study finds — and it's getting worse

A new study from research organization Climate Central finds that globally, people lost an average of 56 hours of sleep per year due to warm weather between 2020 and 2025. That’s seven full nights of sleep.

However, not all of the lost hours of sleep are solely attributed to warmer temperatures. The study, which examined 1,338 cities globally, says about 10% — roughly five-and-a-half hours of lost sleep — is due to warming that was caused by climate change.

“Sleep is closely tied to the body’s ability to cool itself, and higher nighttime temperatures interfere with that cooling process. Warmer nighttime temperatures are associated with shorter sleep duration and reduced sleep quality,” Climate Central’s report reads.

“Climate change is increasing nighttime temperatures in many parts of the world and making extremely warm nights more common.”

Creeping numbers

Five extra hours of lost sleep due to climate change may not sound like a lot, but the number has doubled globally since the 1970s, NPR reports, and it’s expected to keep climbing. That’s because overnight temperatures are increasing at a faster rate than daytime ones.

The phenomenon is global, but cities in the Middle East have experienced the highest levels of sleep loss due to climate change, reaching as high as 16 hours annually in some cities, the report reads. (Heat-driven sleep loss in cities like Oman, Saudi Arabia and the United Arab Emirates is estimated somewhere between 55 and 87 hours annually.)

In the U.S., Arizona, Florida and parts of California were impacted the most dramatically. Climate change sleep loss in the U.S. “grew faster than the global average, roughly tripling from just over one hour per year in the early 1970s to about four hours per year in the 2020s,” the report reads.

And yes, air conditioning helps, but its availability is often connected to income — and even if you have access to it, high temperatures can still reduce your sleep.

Fewer Zs

Physicians have long warned about American sleep habits. As far back as 2016, Wayne Giles, M.D., then-director of the CDC’s Division of Population Health, said in a study that “as a nation we are not getting enough sleep.”

Doctors recommend adults get at least seven hours of sleep per night. Failing to do so has been linked with poor health, with impacts including weight gain, diabetes, high blood pressure, heart disease, stroke and depression.

Poor sleepers have also been found to be more irritable, have difficulty concentrating and can suffer from impaired judgment.