For years, parents have been told to enforce a strict digital curfew, ban late-night snacks, and keep teens from exercising before bed—all in the name of better sleep. But a new study out of New Zealand’s University of Otago is flipping that script. Researchers tracked the real-life bedtime habits of 83 adolescents aged 11 to 15, using wearable cameras, accelerometers, and food diaries to get a clear, objective picture of what actually happens in that crucial hour before lights out.

Researchers at the University of Otago fitted teens with wearable cameras and sleep trackers to capture real-life bedtime habits. (Image: University of Otago)

The results? Nearly every teen—99%—used screens before bed. About 63% ate something, and 22% squeezed in some physical activity. And yet, most of them still slept just fine. “Not many teenagers followed current sleep guidelines, but those who did experienced little difference in their sleep,” said lead author Chao Gu, a PhD candidate in Otago’s Department of Medicine.

Researchers at the University of Otago fitted teens with wearable cameras and sleep trackers to capture real-life bedtime habits. (Image: University of Otago)

This matters because the current sleep hygiene rules—no screens, no food, no exercise before bed—are based more on theory than hard evidence. The idea is that screens mess with melatonin, exercise revs up the body, and food (especially sugar or caffeine) disrupts rest. But most of that research relied on self-reported surveys, which can be fuzzy at best. This study, published in Pediatrics Open Science, used cameras and sleep trackers to observe what teens actually did—and how it affected their sleep in real time.

Here’s what they found: screen use didn’t shorten sleep or reduce its quality, though it did delay falling asleep by about 23 minutes. Exercise before bed, while rare, was linked to more sleep—about 34 minutes extra. And eating before bed? No measurable impact on sleep at all, even when snacks included sugar, fat, or caffeine.

So what does this mean for families trying to navigate the nightly bedtime battle? It might be time to rethink the rigid rules and focus more on what works for each individual teen. “Sleep is incredibly important for teenagers to enable them to develop and function at their best,” Gu emphasized. “But so few studies have looked at pre-bed behavior and how it can impact rest using objective measures such as cameras”.

Of course, this doesn’t mean teens should binge TikTok until 2 a.m. or swap dinner for midnight energy drinks. But it does suggest that a little flexibility—say, a light snack or a short scroll—might not be the sleep killer we feared. And that’s a relief for families juggling homework, sports, and the general chaos of adolescence.

The researchers are already working on a follow-up study with a larger group of 10- to 15-year-olds. Their goal? To build stronger, more realistic guidelines that reflect how teens actually live—and sleep. Because in the end, better sleep isn’t about perfection. It’s about balance, understanding, and meeting kids where they are.