Researchers at a Saudi Arabian university surveyed 1,564 college students to understand what affects their sleep quality. They found that using your smartphone right before bed, drinking too much coffee or tea, feeling anxious, and not exercising enough all make it harder to sleep well. Interestingly, things like age and gender didn’t matter much. The good news? All of these sleep-harming factors can be changed. By putting your phone away at night, cutting back on caffeine, managing stress, and moving your body more, students could sleep better and feel healthier.

The Quick Take

  • What they studied: What habits and feelings affect how well college students sleep at night
  • Who participated: 1,564 undergraduate students from Jazan University in Saudi Arabia, surveyed online between April and June 2023
  • Key finding: Using your phone right before bed and high anxiety were the strongest predictors of poor sleep, but exercise, diet, and caffeine intake also played important roles
  • What it means for you: If you’re struggling to sleep, putting your phone away an hour before bed, limiting coffee and tea, and finding ways to manage stress could make a real difference. This is especially helpful if you’re a student dealing with academic pressure.

The Research Details

This study used a cross-sectional design, which means researchers took a snapshot of 1,564 students at one point in time (April-June 2023) rather than following them over months or years. Students completed an online survey that asked about their sleep quality, daily habits, anxiety levels, and how much they used their smartphones. The researchers used a well-established sleep measurement tool called the Pittsburgh Sleep Quality Index (PSQI), which asks detailed questions about how long you sleep, how long it takes to fall asleep, and how rested you feel. They also asked about exercise, diet, caffeine consumption, smoking, anxiety, and smartphone usage patterns. The data was then analyzed using statistical tests to find connections between these factors and sleep quality.

This research approach is valuable because it captures real-world information from a large group of students in their actual living situations. By asking about multiple factors at once—physical habits, mental health, and technology use—the researchers could see which ones matter most for sleep. This helps identify the best targets for helping students sleep better.

The study’s strengths include a large sample size (1,564 students) and the use of a validated, scientific sleep measurement tool. The study was conducted at a specific university in Saudi Arabia, so results may not apply equally to all students worldwide. Because this is a snapshot study rather than a long-term follow-up, we can see associations between factors and sleep but cannot prove that one directly causes the other. The online survey format is convenient but may have attracted students with certain characteristics.

What the Results Show

The most striking finding was that using your smartphone right before bed significantly worsened sleep quality, even when accounting for total daily phone use. Students who used phones at bedtime had noticeably worse sleep scores. Anxiety showed a clear pattern: mild anxiety increased sleep problems slightly, moderate anxiety made them worse, and severe anxiety caused the biggest sleep disruption. Students who exercised regularly slept better than those who didn’t (sleep quality scores of 7.67 vs 8.19, where higher numbers mean worse sleep). Those who ate unhealthy diets also reported worse sleep (scores of 7.33 vs 8.10). High caffeine intake—especially more than 3 cups of coffee daily—was linked to poorer sleep quality. The effect was dose-dependent, meaning more caffeine meant worse sleep.

Interestingly, demographic factors like age and gender were not significantly associated with sleep quality differences. This suggests that lifestyle choices matter more than who you are. The study also found that tea and soft drink consumption contributed to sleep problems, though coffee had the strongest effect. Smoking and qat use (a plant stimulant common in the region) were mentioned as factors, though specific results weren’t detailed in the abstract.

These findings align with existing research showing that caffeine, anxiety, and screen time before bed harm sleep. However, this study is valuable because it examined all these factors together in a large student population, showing that smartphone use at bedtime is particularly important—not just because of total screen time, but specifically because of when you use it. The strong connection between anxiety and sleep quality confirms what many sleep researchers have found.

Because this is a cross-sectional study, we cannot say that poor sleep habits cause anxiety or vice versa—only that they occur together. The study was conducted at one university in Saudi Arabia, so results may differ in other countries or cultures. Students self-reported their habits, which means some may have underestimated phone use or caffeine intake. The online survey format may have attracted students with certain characteristics, potentially skewing results.

The Bottom Line

Strong evidence supports: putting your phone away at least 30-60 minutes before bed, limiting caffeine (especially after 2 PM), exercising regularly, and eating a balanced diet. Moderate evidence supports: seeking help for anxiety through counseling or stress management techniques. These changes are most effective when combined rather than done individually.

College and university students will benefit most from these findings, especially those struggling with sleep or academic stress. Anyone dealing with anxiety or heavy caffeine use could also benefit. These recommendations are safe for most people, though those with anxiety disorders should consult healthcare providers about professional support.

You may notice better sleep within 1-2 weeks of putting your phone away before bed. Exercise and diet changes typically show benefits within 2-4 weeks. Managing anxiety may take longer and often requires professional support. Consistency matters more than perfection.

Want to Apply This Research?

  • Track daily sleep quality (1-10 scale), caffeine intake (number of cups), exercise duration (minutes), and phone-free time before bed (minutes). Monitor these weekly to see patterns.
  • Set a phone curfew 1 hour before your target bedtime. Use the app to log when you put your phone away and rate your next morning’s sleep quality. Create a streak counter to motivate consistency.
  • Weekly review of sleep quality vs. phone use timing, caffeine intake, and exercise. Look for patterns over 4-week periods. Share progress with friends for accountability. Adjust one habit at a time rather than changing everything at once.

This research shows associations between lifestyle factors and sleep quality but does not prove direct causation. Results are from a specific student population and may not apply universally. If you have persistent sleep problems or severe anxiety, consult a healthcare provider or sleep specialist. This information is educational and should not replace professional medical advice. Always discuss significant lifestyle changes with your doctor, especially if you take medications or have underlying health conditions.