Even a small amount of light exposure during sleep may change the shape and function of heart muscles, increasing the risk of future heart disease, a new study found.
“Light pollution has emerged as a new risk factor for cardiovascular disease,” said senior study author Dr. Lu Qi, the HCA Regents Distinguished Chair and Professor and director of the Tulane University Obesity Research Center in New Orleans.
“Our findings, together with evidence from other studies, suggest that reduction of nighttime light exposure should be considered as one of the potential strategies for preventing heart disease by clinicians and policy makers,” Qi said in a statement.
For quality sleep, experts say the bedroom should ideally be a maximum of 1 lux, which is quite dark. A lux is a method of measuring illumination levels set by the International System of Units — 3 lux is the equivalent of moonlight or light bleeding under a closed bedroom door, according to experts.
In this study, researchers found the heart muscle walls of people exposed to more than 3 lux of light while asleep thickened in ways that reduced the efficiency of the heart’s pumping action.
