Late bedtimes linked to heart disease

"Burning the midnight oil may be hazardous to your health. Men who go to bed after midnight have significantly more arterial stiffening - an early stage of atherosclerosis, or hardening of the arteries - than men who turn in earlier, a new study shows. Several large studies have linked chronic sleep loss to heart disease, diabetes, obesity, and other health problems, says Yu Misao, MD, of the Misao Health Clinic in Gifu, Japan. But whether bedtimes also have an influence on heart health has not been explored, he tells WebMD." - WebMD