Researchers from Duke University and Yale University have identified a clear link between using social media in the evening and disruptions to sleep quality. The findings were published in the journal Sleeping Pill.
The study examined a vast trove of online activity, analyzing 120 million posts from 44,000 users over a span of 15 years. The results show a consistent pattern: when a person posts about an hour before their typical bedtime, they tend to go to bed later than usual. On average, bedtimes shifted by roughly one to three hours past the usual sleep window.
Experts propose that waiting for responses on social platforms elevates dopamine levels, which can keep the mind active and delay the onset of rest. This aligns with prior observations that higher dopamine activity correlates with heightened mental alertness and wakefulness, especially in the hours leading up to sleep. A steady routine of late-evening engagement may thus hinder the transition to restful sleep for many users.
Another body of work has shown that the blue light emitted by phones and tablets can suppress melatonin production, further interfering with sleep quality. Together, these factors help explain why late-night scrolling is often followed by difficulties falling asleep and a less refreshing night’s rest. The combined evidence from multiple research teams suggests that moderating evening screen time could support better sleep health, particularly for individuals in Canada and the United States who frequently use social media after dark. This conclusion is supported by ongoing investigations into how digital habits shape circadian rhythms and overall sleep patterns, with findings published across medical and behavioral science journals.