I don’t think short videos are evil. TikTok, Reels and Shorts are often funny and now and then genuinely useful. The trouble is the format, which is built to keep you watching and is frighteningly good at it. Everyone I know has looked up after an hour and wondered where it went.

Whether you quit is your call. But you should at least know what the hour costs, and researchers have started putting numbers on it.

What the research finds

The research is young and mostly correlational, so hold it loosely. Still, the pattern shows up everywhere they look: attention, mood, sleep, even what we eat and buy.

  • Attention. A 2024 study found that people with signs of short-video addiction scored lower on attention control and executive function. A feed of constant novelty trains you to expect it, and then a book feels slow.
  • Mood. In one experiment, reported in a systematic review, 20 minutes on TikTok raised depression scores by 12% and anxiety by 15% on average. Twenty minutes. The boredom relief wears off long before that.
  • Sleep. Watching in bed produces what researchers call cognitive arousal, which is your brain winding up exactly when it should be winding down. You sleep less, and worse.
  • Work. Each interruption costs around 23 minutes to fully refocus, and an autoplaying feed interrupts you more reliably than anything else on your desk.
  • Eating and buying. About half the students in a University of Rhode Island survey changed their diet because of something they saw on social media, and roughly 3 in 8 people say they’ve bought something after watching a short video. The feed reaches your wallet too.

What to make of it

A few Reels won’t wreck your life. I want to be clear about that, because the doom pieces on this topic are their own kind of tiresome. The effects are small on any given day. They just don’t stay small, and they land mostly on sleep and focus, which are the two things you can least afford to lose.

Two questions follow. If we know all this, why is it still so hard to stop? And what actually helps? The first is in Why is it so hard to stop scrolling?, the second in How to watch short videos on your own terms.

References