Large‑Scale UK Biobank Study Tracks 300,000 Adults The researchers followed more than 300,000 middle‑aged and older participants in the UK Biobank cohort, classifying about 8 % as night owls, a quarter as early birds and the remainder as average sleepers based on self‑reported sleep‑wake preferences. The longitudinal design spanned 14 years, enabling assessment of first cardiovascular events. This extensive sample provides robust statistical power for the findings [1].

Night Owls Experience 16% Higher Risk of Heart Attack or Stroke Participants identified as night owls faced a 16 % greater chance of a first heart attack or stroke compared with average sleepers. The elevated risk remained after adjusting for age, sex and socioeconomic status. Women night owls displayed overall poorer cardiovascular health metrics than men in the same group [1].

Unhealthy Lifestyle Factors Explain Most of the Risk Gap The analysis linked the excess risk to higher rates of smoking, insufficient sleep duration and poorer diet among night owls. Controlling for these behaviors reduced the risk differential substantially. Researchers attribute the mechanism to circadian misalignment that makes heart‑healthy habits harder to maintain [1].

Experts Recommend Simple Timing and Habit Adjustments Investigators advise quitting smoking, establishing consistent bedtime and wake‑time, and focusing on basic diet and exercise to mitigate danger. Aligning daily schedules with the internal clock improves insulin response and blood‑pressure regulation. The study stresses that modest lifestyle changes can offset the cardiovascular penalty of late‑night activity [1].