Weekend lie-ins could be worse than staying sleep deprived, study says

A weekend lie-in will not make up for the harmful effects of short-changing yourself on sleep during the week, according to a study.

Sleep-starved participants in a US study were more likely to snack late at night, have poorly controlled blood sugar and put on weight, relative to those who were able to sleep nine hours.

Among those who were given time for a catchup sleep at weekends, blood sugar control actually worsened compared with those who only slept for around five hours each and every night.

Sleep deficit during the week is becoming increasingly common as people try to balance work – or school – pressures with family and social commitments, University of Colorado researchers said.

But sleep plays a key role in a regulating the body’s metabolic processes, affecting everything from digestion to stress, and long-term deprivation is linked to increase risk of diabetes and heart disease.

“When we maintain insufficient short sleep schedules during a work or school week, this causes people to eat more than they need – this leads to weight gain,” said Professor Ken Wright, one of the authors of the study published in Current Biology.

“When they eat more they tend to eat after-dinner snacks, altogether this leads to reduced ability to regulate blood sugar levels.”

For the trial the team enlisted 36 healthy adults under the age of 40 to live for two weeks in their sleep and chronobiology lab, where their food intake, light exposure and sleep could be monitored.

The participants were split across three groups: one was allowed to sleep nine hours a night for nine nights; one restricted to five hours a night; and the final group had their sleep restricted for five days but was allowed to sleep as much as they wanted at the weekend, and then went back on to restricted sleep.

They found the weekend group reported more disrupted sleep and only managed to recover around 66 minutes with their weekend lie-in.

Insulin sensitivity – the body’s ability to regulate fluctuations in blood sugar – was reduced by twice as much as in the chronic sleep deprivation group, with the cells of in the muscles and liver being particularly affected.

“This isn’t something we found in people who maintained chronic insufficient schedules, this could be a worsening of the body’s ability to regulate blood sugar for those specific tissues after a weekend of recovery,” Professor Wright said.

“It could be that the yo-yoing back and forth – changing the time we eat, changing our circadian clock and then going back to insufficient sleep – is uniquely disruptive,”

The team recommended adults maintain around seven hours a night consistently in the interest of good health, chiefly by cutting down on post-work TV or other entertainment.