Bright Outdoor Light at Night May Increase Stroke Risk

Too much exposure to bright outdoor lights at night may increase a person’s stroke risk, new research suggests.

The study involved more than 28,000 people living in a large city in China. Researchers found that people exposed to the highest levels of artificial outdoor light at night had a 43% increased risk of developing cerebrovascular disease, as compared to those with the lowest levels of exposure. Cerebrovascular disease includes stroke and other conditions affecting blood flow to the brain.

Previous studies have linked increased exposure to bright, artificial light to the development of cardiovascular disease, which are conditions related to blood flow in arteries. Researchers said their study is one of the first to explore the relationship between light at night and brain health.

“Our study suggests that higher levels of exposure to outdoor artificial light at night may be a risk factor for cerebrovascular disease,” study co-author Dr. Jianbing Wang said in a news release.