Turning on the ‘for you’ feed on X shifted political opinions, but turning it off did not

A field experiment shows that turning on the algorithmic feed on the social-media platform X in 2023 shifted political opinions to the right, whereas turning it off had no effect on political attitudes. The algorithmic feed led users to follow more right-leaning accounts, which they continued following when the algorithm was off. Users started and continued following right-wing accounts even after switching back to a chronological feed.