Meta shut down internal research into the mental health effects of Facebook and Instagram after finding causal evidence that its products harmed users’ mental health, according to unredacted filings in a class action by U.S. school districts against Meta and other social media platforms.

In a 2020 research project code-named “Project Mercury,” Meta scientists worked with survey firm Nielsen to gauge the effect of “deactivating” Facebook and Instagram, according to Meta documents obtained via discovery. To the company’s disappointment, “people who stopped using Facebook for a week reported lower feelings of depression, anxiety, loneliness and social comparison,” internal documents said.

Rather than publishing those findings or pursuing additional research, the filing states, Meta called off further work and internally declared that the negative study findings were tainted by the “existing media narrative” around the company.