Alarming news about lie-ins

Study finds habit could kill, but sleep on it to decide

CAN enjoying late nights and lazy lie-ins at the weekends kill you? That was the alarming claim made recently by US researchers, who say the habit can raise risks of dying from heart disease by 11%.

The danger lies in what sleep scientists at the University of Arizona in Tucson, in the US, call “social jet lag”, where changing our sleep patterns at the weekend knocks our bodies and brains out of kilter.

Sierra Forbush, a research assistant for the university’s Sleep and Health Research initiative, who led the study, says changing your sleeping habits at the weekend can wreak havoc on your biological clock.

A survey of 984 adults, published in the journal, Sleep, found a link between people who habitually went to bed and rose late on weekends and an increased rate of cardiovascular disease and fatigue – although it’s not clear why.

Other studies have found links between lie-ins and other physical and mental problems. In 2015, a study of 225 volunteers by health psychologist Dr Patricia Wong at the University of Pittsburgh warned significant shifts in sleep routines between workdays and weekends could raise the risk of diabetes.

Many had fatter waists and higher levels of sugar and fat in the blood – classic warning signs for diabetes reported Wong in the Journal of Clinical Endocrinology and Metabolism.

Lie-ins may also diminish your ability to think. A study in April by Dr Michael Scullin, director of the Sleep Neuroscience and Cognition Laboratory at Baylor University in Texas, tested 28 students and found that when they caught up on lost weekday sleep with long lie-ins, they performed significantly worse in tests of attention and creativity.

“Consistent habits are at least as important for our cognitive abilities as total length of sleep,” concluded Scullin in the Journal of Interior Design.

“Irregular sleep is a negative for the intense focus needed for planning, making decisions and correcting errors,” he added.

Yet other studies have shown that lie-ins may be good for our bodies and brains. In January, a study by the University of Chicago suggested they reduce people’s diabetes risk if they’ve been deprived of sleep during the week. Chronic sleep deprivation may increase insulin insensitivity, and catching up on sleep may help undo the damage.

The research, in the journal, Diabetes Care, found that getting only four or five hours’ sleep a night can raise the risk of diabetes by about 16%

But sleeping for nearly 10 hours on two consecutive nights can reverse that damage, claimed sleep disorders expert Dr Esra Tasali, who led the investigation.

Her study found lie-ins improved the body’s response to insulin by 23%. And rather than lie-ins causing fatter waistlines, other research suggests the opposite.

In 2014, University of Chicago investigators reported in the journal Appetite a 90-minute lie-in at the weekend reduces hunger pangs.

It’s also known sleep deprivation may disrupt the activity of appetite hormones such as leptin.

The study concluded that: “Obtaining adequate sleep is associated with less desire for high-calorie foods in overweight young adults who habitually curtail their sleep.”

It appears catching up with lost sleep may restore healthy levels of appetite hormones.

Researchers are similarly at odds over whether weekend lieins can boost your brain power.

In 2010, Dr David Dinges, chief of the Division of Sleep and Chronobiology at the University of Pennsylvania, reported in the journal Sleep that a 10-hour sleep can boost mental energy, alertness and attention after a week of restricted sleep.

Should we be lying awake at night worrying about the pros and cons of enjoying a lie-in?

“It would be a shame to be scared of a lie-in,” says Jim Horne, a sleep neuroscientist and emeritus professor of psychophysiology at Loughborough University.

He thinks it’s not sleep “or the lack thereof” but chronic stress that’s the main culprit behind poor-quality sleep and physical health.

Indeed, with diabetes, numerous studies indicate that chronically raised levels of stress hormones can interfere with the regulation of bloodsugar levels.

Joseph Gannon, chief sleep physiologist at the Sleep Disorders Clinic in London, believes there is little to fear from the odd lie-in. He adds, however, that he does see patients suffering from “extreme” weekend lie-ins.

Dr Neil Stanley, an independent sleep consultant, says weekend lie-ins should only be necessary for “night owls”, people who function best in the evenings.

“If you’re a night owl, then you are probably sleep-deprived, as you will have gone to bed late and will then have to get up on weekday mornings before your system is ready.

“In all probability, being sleep-deprived during the week is worse for you than having a lie-in at the weekend.” – Daily Mail