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Sugar And Sleep: More Rest May Dull Your Sweet Tooth

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In one study, participants who routinely got less than seven hours of sleep were coached to extend their sleep time. They also changed their diets, without being asked — taking in less sugar each day.

Listen up, night owls: If you're sleeping six or fewer hours per night, you're not doing your health any favors.

A new study finds that getting the recommended seven to nine hours of sleep per night may help you tame your sweet tooth.

Researchers at King's College London recruited "short sleepers" — that is, people who routinely sleep less than 7 hours per night. The participants were coached on strategies to extend sleep time, such as cutting back on caffeine, reducing screen time and sticking to a regular bedtime each night.

Based on this coaching, the short sleepers began to sleep about one hour more per night. And, here's the fascinating part: They also changed their diets — without being asked.

"We found that those who extended their sleep [also] reduced their intake of added sugars by about 10 grams per day," explains one of the study authors, Haya Al Khatib, a doctoral candidate at King's College London.

That's about 40 calories worth of sugar, which is not a huge change. But over time, a small, daily decline in sugary foods could make a difference.

The study, which is published in the American Journal of Clinical Nutrition, is small. It included just 42 normal-weight participants, and it doesn't prove that sleep is the key to diet change. But the findings serve up more evidence that our sleep can influence our eating habits and waistlines.

A study published back in 2013 found that just five days of shortened sleep can lead to weight gain. In that study, people were allowed to sleep for just five hours for a five-day period. They gained, on average, almost two pounds.

And as we've reported, the timing of meals — independent of sleep — can also influence how our bodies respond to all the calories we eat. For instance, a study published in the International Journal of Obesity found that people who eat their main meal early in the day are more successful at losing weight, compared with people who eat a heavy, late-night meal.

It seems, we humans are time-keeping machines. And we require regular sleeping and eating habits to keep our body clocks in sync — and our health in check.

Copyright 2018 NPR. To see more, visit


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