Google News – There’s nothing worse than trying to fall asleep at night while the light from a nearby streetlamp beams through your window. Beyond just being a nuisance, nighttime light pollution can have serious health effects, including raising your risk of heart disease.
A recent presentation at the American Heart Association’s Scientific Sessions 2025 claims to have found the reason nighttime light pollution negatively influences heart health: the more exposure we have to artificial light during the night, the more stressed our brains become.
This stress causes a chain reaction throughout the body, one result of which is inflamed arteries that can lead to heart disease.
“We know too much exposure to artificial light at night can harm your health, particularly increasing the risk of heart disease. However, we did not know how this harm happened,” said Julio Fernandez-Mendoza, director of behavioral sleep medicine at Pennsylvania State University College of Medicine, in a press release.
“This study has investigated one of several possible causes, which is how our brains respond to stress. This response seems to play a big role in linking artificial light at night to heart disease.”
How Can Artificial Light Damage Our Heart?
To investigate how nighttime light-induced stress increases the chances of heart disease, researchers analyzed data from 466 healthy Americans across a 10-year period.
This data included the patients’ health records, brain and heart scans, and measurements of nighttime light activity within the participants’ homes.
Most unique to this study was the use of a combined Positron Emission Tomography/Computer Tomography (PET/CT) scan.
According to Shady Abohashem, an instructor at Harvard Medical School, “using both imaging techniques together allows for the measurement of brain stress activity and arterial inflammation in a single scan.”
This first-of-its-kind analysis revealed some important details about the relationship between nighttime light pollution and heart disease …
