Going to sleep at 10pm regularly could result in a lower risk of developing heart disease, new research has found.
For the research published in the European Heart Journal, UK experts studied 88,000 volunteers and concluded that matching sleep to the body clock may account for a reduced risk of heart attacks and strokes.
The study collected data on the sleep-wake times of the volunteers over a week using a wristwatch-like device.
Participants also completed demographic, lifestyle, health, and physical assessments and questionnaires.
The volunteers then went for a new diagnosis of cardiovascular disease, which was defined as a heart attack, heart failure, chronic ischaemic heart disease, stroke, and transient ischaemic attack.
The researchers observed what happened to the volunteers in terms of heart/circulatory health over an average of six years.
The findings showed that just over 3,000 of the adults developed cardiovascular disease, many of which occurred in people who went to bed later or earlier than the “ideal” 10pm to 11pm.
The researchers also found that the link persisted after adjustments were made for sleep duration and irregularity.
Speaking on the findings, David Plans, author of the study who works with the health technology firm Huma, said the research cannot conclude on causation.
“The results suggest that early or late bedtimes may be more likely to disrupt the body clock, with adverse consequences for cardiovascular health,” he added.
“The riskiest time was after midnight, potentially because it may reduce the likelihood of seeing morning light, which resets the body clock.”
The researchers said the findings appear to be stronger in women than men, although the reasons for this remain unclear.
Regina Giblin, a senior cardiac nurse at the British Heart Foundation, said: “This large study suggests that going to sleep between 10 and 11 pm could be the sweet spot for most people to keep their heart healthy long-term.
“However, it’s important to remember that this study can only show an association and can’t prove cause and effect. More research is needed into sleep timing and duration as a risk factor for heart and circulatory diseases.
“Getting enough sleep is important for general wellbeing as well as our heart and circulatory health. Most adults should aim for seven to nine hours of sleep per night. But sleep isn’t the only factor that can impact heart health.”