In cities that shine brighter at night, more people are struggling with insomnia

In cities where people are exposed to more artificial light at night, more people are posting on social media about insomnia, according to international research. The team measured the artificial brightness of over 300 Chinese cities at night, and used insomnia-related social media posts from residents of those cities to compare how common the condition likely was in different areas. The researchers say using data from over a million insomnia-related posts, they found the brighter a city was, the more people were posting about insomnia. This link was stronger when air pollution was worse or temperatures were extreme, the researchers add.