Social Media Toxicity and Mental Health
What happens to mental health when toxic content is removed from social media?
with Francesco Capozza, Kylan Rutherford, and Mateusz Stalinski
- presented at the 2026 NBER Summer Institute (Digital Economics and AI)
Abstract
Does exposure to social media toxicity, holding platform access constant, affect mental health? We randomly assign participants to a content-level intervention hiding toxic posts and comments on Facebook, X, and Reddit via a browser extension. We observe N = 664 desktop users over a six-week study period in two waves – one during the 2024 US election campaign and one outside of it. Contrary to basic intuition, hiding toxicity worsens mental health. The treatment increases an index of GAD-7 and PHQ-8 symptoms by 0.15σ, and the share of respondents with symptoms above the moderate cutoff rises by 12.1 pp. A QALY-based calibration indicates a welfare cost of about $158 per treated participant. We find evidence consistent with higher loneliness, lower relative moral self-view, and lower exposure to in-group political toxicity as mechanisms. We conclude that curbing toxic content can impose unintended psychological costs, even where it offers other social benefits.