A new study suggests that exposure to even low levels of light while sleeping may affect the structure and function of the heart, potentially increasing the risk of future cardiovascular problems.
Researchers analysed more than 11,000 people from the UK Biobank and found that those exposed to more than three lux of light at night had thicker heart muscle walls and reduced flexibility of the heart, changes that may affect its pumping efficiency.
Experts say excessive nighttime light may also contribute to shorter or poorer-quality sleep, while factors such as stress, blood pressure and heart rate could further influence cardiovascular health.
To reduce nighttime light exposure, experts recommend using blackout curtains or shades, switching off unnecessary lights and keeping phones and digital displays away from the bed. If some light remains, a dim, warm-coloured night-light or sleep mask may help.
The researchers, however, noted that the study does not establish that nighttime light directly causes heart disease and said further research is needed.
