Can lack of sleep make you fat?

New study suggests just one sleepless night can make your body store extra fat

Sleep, bed

A study in Sweden has shown how a lack of sleep can make your body store extra fat and break down muscle.

Researchers at Uppsala University took fat and muscle samples from 15 healthy men, once after a good night’s sleep and once after they stayed awake all night.

“After the sleepless night, the participants’ muscles showed signs of protein breakdown. Their fat tissue, in contrast, had elevated levels of proteins and metabolites that are involved in promoting fat storage,” reports the New Scientist.

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“Staying awake all night also appeared to change the expression of several genes in fat tissue that are associated with obesity and type 2 diabetes.”

Jonathan Cedernaes, an author of the study, published in Science Advances, said it helped to explain why insomniacs and shift workers are more likely to become overweight or suffer from type 2 diabetes. A lack of sleep appears to restrict hormones that maintain muscles and increase levels of cortisol, which encourages fat storage.

Cedernaes’s team are looking into whether certain foods or exercise regimes could help to reverse these effects.

“It may be the case, for example, that eating protein-rich foods or doing resistance training might reduce the risk of muscle degradation,” he says.

Another 2016 study by the University of Chicago found that, after cutting its participants’ sleep from 8.5 hours to 4.5 hours, they were more likely to reach for junk food the next day.

Dr Erin Hanlon, one of the leaders of the study, said having enough sleep makes it easier to control yourself when you see unhealthy food.

“But if you’re sleep deprived, your hedonic drive for certain foods gets stronger, and your ability to resist them may be impaired. So you are more likely to eat it. Do that again and again, and you pack on the pounds,” she said.

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