For many Americans, TikTok is more than entertainment — it is a habit, and in some cases, an addiction. Jon Freilich, a 51-year-old operations manager in California, described his daily use of the app as uncontrollable. “I’ve never smoked or used drugs, so I don’t know what chemical addiction feels like, but I feel like I’m addicted to TikTok,” he said, noting that his daily watch time increased by more than 50 percent last year. Users like Freilich are drawn into an endless stream of hyper-personalized videos, carefully curated by TikTok’s opaque algorithm.
Despite its ubiquity, TikTok shares little information about how its recommendation system works. Researchers and journalists have relied on bot accounts and surveys, but none fully captures human behavior on the platform. To better understand its impact, the Washington Post partnered with readers to collect TikTok watch histories from 1,100 users, creating a database of roughly 15 million videos viewed over six months in 2024. The analysis highlighted how effectively TikTok encourages even light users to watch more, swipe faster, and open the app more frequently over time.
Among participants, lighter users initially spent about 32 minutes per day on the app. Within a week, that number jumped over 40 percent to 45 minutes. Power users, who were already spending more than four hours a day, saw a slight dip in watch time. Over five months, casual users increased their daily watch time to over 70 minutes, while heavy users continued to spend four hours or more on the app. Both groups began swiping faster and opening the app more frequently, illustrating the app’s capacity to foster compulsive behaviors.
Experts say TikTok’s design plays a key role in this engagement. Users scroll through short videos, often feeling in control of the content, yet the algorithm drives them toward more personalized and rewarding videos. “It’s not really that you as the user, or we as users, get to control how we engage with the app but that the app engages us,” said Thomas Essmeyer, a researcher at the University of Bremen. Behavioral psychologists note that this pattern can lower self-control and encourage impulsive behaviors, including phubbing, where users pay more attention to their screens than to people around them.
TikTok’s internal documents, revealed as part of a multistate lawsuit, suggest that habits form after watching just 260 videos, roughly 35 minutes of content. Users report losing track of time, binge-watching content that ranges from music clips to “storytime” videos that highlight personal anecdotes or dramatic narratives. By September 2024, lighter users had expanded their content consumption to include a broader range of videos, including political content ahead of the U.S. election.
The app’s impact on the brain has also drawn attention. Research indicates that watching personalized TikTok videos activates the reward system in ways similar to money, food, or other pleasurable stimuli, while affecting areas linked to attention and self-control. Marc Potenza, a psychiatry professor at Yale, said that these effects may increase craving and reinforce habitual scrolling.
Some users have tried limiting their time on the app. Casey Lumley, a college student in Utah, set daily limits after realizing TikTok interfered with her ability to think and focus. Experts recommend strategies such as turning off notifications, setting manual screen time limits, or using third-party apps to add friction to the scrolling experience. Others find that deleting the app from mobile devices and using it only on a desktop reduces compulsive behavior.
“The entire design is completely created as interaction to make you happy for the moment, not for the long term,” Essmeyer said. For many users, the convenience and endless rewards of the platform make it difficult to disengage, creating a loop that can dominate hours of daily life. As the Washington Post’s analysis shows, TikTok’s algorithm not only entertains but shapes behavior, turning casual scrolling into a near-constant habit for millions of Americans.
