Research finds global heating is reducing people’s sleep, especially among women and older people, with serious health impacts.
The largest study to date has found that rising temperatures driven by the climate crisis are affecting people’s sleep across the world, reports The Guardian.
The study found that the average global citizen is already losing 44 hours of sleep a year, leading to 11 nights with less than seven hours’ sleep, a standard benchmark of sufficient sleep.
Some groups are affected much more than others. The sleep loss per degree of warming is about a quarter higher for women than men, twice as high for those over 65 years old and three times higher for those in less affluent nations.
Women’s bodies cool earlier in the evening than men’s when going to sleep, meaning higher nighttime temperatures may have a bigger impact on women.
The researchers used data from sleep-tracking wristbands used by 47,000 people over a total of 7 million nights and across 68 countries.
Previous studies have shown that rising temperatures damage health, including increased heart attacks, suicides and mental health crises, and accidents and injuries, as well as reducing the ability to work.
The lead researcher, Kelton Minor from the University of Copenhagen, Denmark, said: “Growing numbers of people in many countries around the world do not sleep enough.”
“In this study, we provide the first planetary-scale evidence that warmer than average temperatures erode human sleep.”