When it comes to heart health, researchers believe there can only be one answer for how much sleep you need a night.
The typical answer someone might give when asked how much sleep a person needs per night is usually around eight hours.
However, new research conducted by an international team has found what it calls the ‘sweet spot’ of a good night’s sleep, specifically for heart health.
Presenting its findings at this year’s European Society of Cardiology Congress, the team of researchers led by Dr Epameinondas Fountas of the Onassis Cardiac Surgery Centre in Greece said that until now, little was known about the impact of sleeping on the cardiovascular system.
This study, he explained, used a meta-analysis that included 11 prospective studies of more than 1m adults without cardiovascular disease published within the last five years.
Two groups – one with typically fewer than six hours’ sleep and one with more than eight hours’ sleep – were compared to a reference group that overall had somewhere between six and eight hours of sleep.
A lie-in won’t kill you
After looking through the figures, the researchers found that both short and long sleepers had a greater risk of developing or dying from coronary artery disease or stroke.
Compared to adults who slept between six and eight hours a night, short and long sleepers had 11pc and 33pc greater risk, respectively, of developing or dying from coronary artery disease or stroke during an average follow-up of 9.3 years.
“Our findings suggest that too much or too little sleep may be bad for the heart,” Fountas said.
“More research is needed to clarify exactly why, but we do know that sleep influences biological processes like glucose metabolism, blood pressure and inflammation, all of which have an impact on cardiovascular disease.”
Fountas added that one of the study’s strengths is that it only includes prospective studies, avoiding recall bias that often leads to significant error in studies.
“Having the odd short night or lie-in is unlikely to be detrimental to health, but evidence is accumulating that prolonged nightly sleep deprivation or excessive sleeping should be avoided,” he said.