AT least five hours sleep a night may cut the over-50s’ chances of multiple chronic health problems, researchers say.
Ill health can disrupt sleep, but poor sleep may also be a forewarning or a risk itself, they say.
There is evidence sleep helps restore, rest and rejuvenate the body and mind – but why the “golden slumber number” might matter remains unclear.
The PLoS Medicine study tracked the health and sleep of UK civil servants.
All of the about 8,000 participants were asked: How many hours of sleep do you have on an average weeknight?” Some also wore a wrist-watch sleep tracker.
And they were checked for chronic conditions, including diabetes, cancer and heart disease, over two decades of follow-up:
Those who slept five hours or less around the age of 50 had a 30% greater risk of multiple ailments than those who slept seven hours
Shorter sleep at 50 was also associated with a higher risk of death during the study period, mainly linked to the increased risk of chronic disease
Experts generally recommend about seven or eight hours, the researchers, from University College London and Paris Cité University, say.
Scientists do not know for sure, but it is clear that sleep helps the brain process memories and is good for mood, concentration and metabolism.
Sleep is also an opportunity for the brain to be cleared of waste.