Researchers have linked brighter night-time light exposure to elevated risks of five major cardiovascular diseases. Circadian rhythms govern fluctuations in blood pressure, heart rate, platelet activation, hormone secretion, and glucose metabolism. Long-term disruption of those rhythms in animal and human studies have produced myocardial fibrosis, hypertension, inflammation, and impaired autonomic balance. Researchers conducted a prospective cohort analysis to assess whether day and night light exposure predicts incidence of cardiovascular diseases and whether relationships vary with genetic susceptibility, sex, and age. Data came from 88,905 UK Biobank participants, average age 62.4 ± 7.8 years and 56.9% female, who wore wrist-based light...