Common bedroom mistake could be quietly taking a toll on your health, experts say

A new study from Tulane University has found a link between nighttime light exposure and a higher risk of cardiovascular disease. The researchers discovered that exposure to more than 3 lux of light, roughly the brightness of moonlight, was associated with increased risks of heart failure, atrial fibrillation, heart attack, stroke, and cardiovascular death.

According to sleep expert Chelsie Rohrscheib, Ph.D., the circadian rhythm, or the brain's internal 24-hour clock, is strongly influenced by light entering the eyes. Light exposure signals the brain to suppress melatonin production, a hormone that helps regulate the timing of sleep, while low light levels signal the brain to produce more melatonin.

Rohrscheib warned that consistent light exposure can chronically reduce overall sleep quality, which can negatively impact many biological processes, including body and brain restoration, hormone release, immune system functioning, and cognitive processes such as memory consolidation and metabolic regulation.

The study also noted that sleep impairment is linked to increased risk of mortality, and that certain groups, such as shift workers, children, older adults, and individuals with insomnia or mood disorders, may be more sensitive to nighttime light than others.

Experts agree that dim, warm, red-toned night lights cause far less circadian impact than brighter light, and that implementing changes to cultivate a healthy sleep environment, such as using blackout curtains or dim, warm night lights, can help improve sleep quality.

Rohrscheib noted that while blackout curtains are recommended for optimal sleep, it's not necessary to have absolute darkness to maintain a healthy sleep environment.