"You also increase the likelihood of having severe sleep apnea by 40%," lead author says.
The study used about two years of sleep data from more than 125,000 people worldwide.
The risk of having a severe sleep Apnea event when it was very hot out nearly doubled in many northern countries, like Europe and Russia.
Another study in China found that a 10-degree Celsius (18-degree Fahrenheit) jump in temperatures cut sleep time by about 10 minutes per night.
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In the world of social enterprises, failure is a cringe-worthy moment nobody wants to talk about. But, social entrepreneurs can benefit from their failures.