"A New, More Rigorous Study Confirms: The More You Use Facebook, the Worse You Feel," HBR

And despite the ubiquitous "Smiley Face," Facebook makes most users depressed.

"A New, More Rigorous Study Confirms: The More You Use Facebook, the Worse You Feel"

Harvard Business Review

https://hbr.org/2017/04/a-new-more-rigorous-study-confirms-the-more-you-use-facebook-the-worse-you-feel