Night owls tend to experience worse heart health in middle age and beyond, underscoring the value of targeted interventions that help to mitigate risk for people who naturally stay up late, research has found.
New research published in the Journal of the American Heart Association – and reported by SciTechDaily – suggests that our chronotype, when the body is naturally inclined to stay active and to sleep, may play a key role in long-term cardiovascular health.
Researchers analysed a sample of over 320,000 UK Biobank participants, aged 39-74, with no known cardiovascular disease. They split them into three groups based on chronotype: definitely evening, for night owls; definitely morning, for early birds; and intermediate for those who were unsure or had no preference either way.
Their results found that night owls, especially women, had a 79-percent higher likelihood of experiencing poorer overall heart health than those in the intermediate group, where most people tend to fall.
Much of that risk, though, was connected to lifestyle factors associated with those who stay up late, opening the door for targeted interventions.
[See more: No, a nightly glass of wine isn’t ‘good for your heart’]
Researchers assessed participants’ cardiovascular health using Life’s Essential 8, a multi-factoring scoring system developed by the American Heart Association (AHA). It focuses on factors linked to good heart health, including behaviours like healthy diets, regular physical activity, avoiding tobacco and getting quality sleep, as well as health measures like weight, cholesterol, blood sugar and blood pressure.
Morning people were 5-percent less likely to have poor overall scores than those in the intermediate group, who in turn were less likely than evening people. Night owls not only tended to have poorer scores, they also showed a 16-percent greater risk of experiencing heart attack or stroke during the median follow-period of about 14 years.
Part of the issue is the frequent mismatch between a night owl’s internal body clock and the day-to-night light cycle – or their typical schedule. But there are also behavioural factors that are more common among those who stay up late, such as poorer diet quality, smoking, and inadequate or irregular sleep.
“Evening types aren’t inherently less healthy, but they face challenges that make it particularly important for them to maintain a healthy lifestyle,” Dr Kristen Knutsen, volunteer chair of the 2025 AHA statement, said in a press release. She emphasized how targeted programmes can help night owls improve behaviours and reduce their risks.
