Did you know that bright lights before bed can disrupt your sleep and worse—they may actually increase your risk for major diseases.

Overexposure to artificial light at night has be tied to breast cancer, obesity, diabetes, and depression, according to a new paper from University of Connecticut cancer epidemiologists.

"It's become clear that typical lighting is affecting our physiology," said lead researcher Richard Stevens, Ph.D. in a press release. Not enough sunlight during the day combined with too much artificial light at night are very likely disrupting our natural wake/sleep cycle, or circadian rhythm.

The risk of disease is really focused is on your evening light intake. Although his team’s study is not definitive, it does present the growing body of evidence in favor of these suspected long-term implications of lighting on our health.

"It doesn't mean you have to turn all the lights off at 8 p.m. every night, it just means if you have a choice between an e-reader and a book, the book is less disruptive to your body clock,” he said. At night, the better, more circadian-friendly light is a dimmer option, he adds, which means that e-readers on low luminosity are even passable.