Clocks go back: The health benefits of an extra hour's sleep

Not only will Brits be able to enjoy an extra hour's sleep on Saturday night, but their health and brain power are also set to benefit from the extra shut-eye.

As Daylight Saving Time ends, the UK will switch from British Summer Time (BST) to Greenwich Mean Time (GMT), heralding the start of lighter mornings but darker evenings.

Daylight Saving Time ends at 2am on Sunday morning, meaning that the clocks are then put back, so instead of it being 2.01am on Sunday, the clocks change to 1.01am.

Research has shown that a small boost to the amount of sleep we get each night can improve memory and increase learning capacity, as well as protecting against illnesses such as diabetes, cancer and heart disease, and also inflammation and stress.

Drawing on 20 years of research into sleep, Professor Matthew Walker, director of the Centre for Human Sleep Science at Berkeley California, explained that an extra 60 to 90 minutes of sleep per night "boosts the learning capacity of the brain, significantly increasing memory retention of facts and preventing forgetting."

Prof Walker conducted a study which demonstrated that during a demanding memorising task, test subjects who were allowed extra nap time performed better than those who did not.

His team found the brain's ability to learn was linked to sleep spindles - which are fast pulses of electricity generated during REM (rapid eye movement) sleep, which accounts for 25% of total sleep time in adult humans.

Spindle-rich sleep, which is said to occur in the second half of the night, helps with the brain's ability to create new memories by "clearing a path to learning".

It's not just improved brain power, that well-rested Brits could benefit from on Sunday, but a link has also been shown between an extra hour in bed and protection against illnesses such as diabetes, cancer and heart disease, and also inflammation and stress.

Scientists at the Surrey Sleep Centre in Guildford divided participants in their study in to two groups.

During the first week, one group slept for six-and-a-half hours a night while the other had seven-and-a-half hours of shut-eye. The volunteers then switched their sleep patterns in the second week.

Not only did they researchers find a link between an extra hour in bed and genetic expression which helped to protect against illnesses such as diabetes, cancer and heart disease, as well as inflammation and stress.

The researchers also found that those who had less sleep struggled with mental agility tasks.

Blood tests revealed that genes associated with processes such as inflammation, immune response and response to stress became more active for those who had less sleep.

The activity of genes associated with heart disease, diabetes and risk of cancer also increased.

They found the reverse happened when the volunteers slept for an extra hour.

Other studies have also backed up the findings that extra time spent asleep is linked to a lower risk of heart disease.

A study published in the Journal of the American Medical Association showed that adults who slept for seven hours a night had a lower chance of having calcium deposits in their arteries than adults who had only six hours of sleep.

According to scientists from the University of Chicago, who conducted the five-year research, "the benefit of one hour of additional sleep was comparable to the gains from lowering systolic blood pressure by 17mm Hg".

Another study, published in the Journal of Sleep Research, found that getting an extra hour of sleep significantly improved blood pressure levels among people with hypertension or pre-hypertension.

While Daylight Saving Time has been linked to an increase in heart attacks.

In a study published in the British Medical Journal, physician Amneet Sandhu of the University of Colorado reported a 24% increase in heart attack admissions at hospitals in Michigan over the course of three years on the Monday after the clocks went forward in spring, when compared with other Mondays throughout the year.

In contrast, they noted a 21% decrease in heart attacks on the Tuesday in the same hospitals after the clocks moved an hour back in autumn.

The extra hour in bed is likely to benefit the majority of people in the country, after a poll conducted by the Royal Society for Public Health which revealed people in the UK slept an average of 6.8 hours, under-sleeping by about an hour a night.