Staying up late is common among the population, and a recent Swedish study confirmed that people who frequently stay up late have almost twice the risk of coronary artery calcification compared to those who wake up early and go to bed early. This study analyzed data from 771 participants aged 50 to 64, excluding those with prior heart disease. The average age of participants is 57.6 years old, with 47.3% being male. All participants underwent coronary CT angiography to evaluate the degree of coronary artery calcification. Research shows that 29% of this middle-aged population has significant coronary artery calcification. Among people who go to bed early and wake up early, 22.2% have obvious coronary calcification, while the proportion of those who frequently stay up late is as high as 40.8%. After considering the confounding factors that affect coronary artery calcification, further analysis found that compared to those who go to bed and wake up early, those who frequently stay up late have a 90% increased risk of coronary artery calcification. Research suggests that in the early stages of disease, circadian rhythms seem to be particularly important for the heart and blood vessels. Frequent staying up late may be related to coronary artery calcification and the process leading to arterial calcification. (Le Xin She) Wen/Yang Jingang (Fuwai Hospital, Chinese Academy of Medical Sciences)