Bad night's sleep? Take two power naps

We all know how frustrating it can be to get through the day when you haven't slept well the night before. You feel irritable and sluggish and your productivity is out the window – some research suggests the effect on your reaction times and other cognitive processes can be similar to being drunk.

Sleep deprivation does more than just make you tired and unhappy. It also comes with health risks, like increasing your chances of weight gain, high blood pressure, and many other potentially serious health conditions.

But there may be a way to counteract these effects after a bad night's sleep. Scientists in France have found that the humble power nap can reverse the damage caused by sleeping poorly, relieving stress and boosting immune levels back up to normal.

“Our data suggests a 30-minute nap can reverse the hormonal impact of a night of poor sleep,” says Brice Faraut, lead author of the study. "This is the first study that found napping could restore biomarkers of neuroendocrine (neural and hormonal) and immune health to normal levels.”

Sleep and your hormones

For the first part of the study, a group of healthy volunteers were put on a very restricted sleep schedule for three days, allowing them to sleep only between 2am and 4am. The sleep deprivation was found to result in high levels of noradrenaline, a stress hormone that also influences heart rate, blood pressure and blood sugar. On top of that, there was also evidence that their immune systems had been disrupted.

After a recovery period, the experiment was repeated with the same volunteers. This time, they were allowed two 30-minute naps, one at 9.30 am and one at 3.30 pm each day. The result? The power naps appeared to reverse the damage caused by sleep loss - particularly the afternoon nap, which allowed for deeper sleep.

"Napping may offer a way to counter the damaging effects of sleep restriction by helping the immune and neuroendocrine systems to recover," Dr Faraut says. "The findings support the development of practical strategies for addressing chronically sleep-deprived populations, such as night and shift workers."

In other words, to improve workplace productivity, the study authors suggest employers could consider letting sleep-deprived workers take a sleep-break in the middle of the day, especially if they've been working at night.

The study was published in the Journal of Clinical Endocrinology & Metabolism.

Learn more about how to sleep better.