Researchers studied over 27,000 UK adults to understand how sleep affects eating habits. They found that people who sleep poorly or don’t get enough sleep tend to eat more unhealthy foods and eat when they’re bored, stressed, or angry rather than when they’re truly hungry. Interestingly, people who sleep too much also showed signs of eating for emotional reasons. The study suggests that improving sleep quality and getting the right amount of sleep might help people make better food choices and maintain a healthier weight.

The Quick Take

  • What they studied: Whether the amount and quality of sleep people get affects what they eat and how they eat it
  • Who participated: 27,263 adults from the UK with an average age of 51 years old. About 40% were women. Most had a healthy weight range, though some were overweight.
  • Key finding: People who sleep poorly or sleep too little are much more likely to eat when they’re bored, stressed, or upset, and they tend to choose unhealthy foods. People who sleep too much also eat more for emotional reasons, though they don’t show as many signs of eating without thinking.
  • What it means for you: If you struggle with your eating habits, improving your sleep might help. Getting enough good-quality sleep could make it easier to eat healthier and avoid eating when you’re not actually hungry. However, this study shows a connection, not proof that bad sleep causes bad eating.

The Research Details

This was a cross-sectional study, which means researchers looked at a large group of people at one point in time and asked them questions about their sleep and eating habits. All 27,263 participants completed a health assessment where they rated their sleep quality on a scale of 1-10 and reported how many hours they typically sleep. They also answered detailed questions about 13 different eating behaviors, including whether they eat when bored, stressed, or angry, how often they overeat, and what types of foods they prefer.

The researchers then used statistical analysis to look for patterns between sleep and eating habits. They adjusted their results to account for factors that might affect the findings, such as age, sex, income level, and where people lived. This helps make sure that any connections they found between sleep and eating weren’t just due to these other factors.

This research approach is important because it looks at real-world eating behaviors in a very large group of people, rather than studying just a few people in a lab setting. The large sample size makes the findings more reliable and representative of the general population. By examining many different eating behaviors at once, the researchers could see a complete picture of how sleep affects eating patterns, not just one or two behaviors.

This study has several strengths: it included a very large number of people, which makes the results more trustworthy, and it looked at many different eating behaviors. However, there are some limitations to keep in mind. The study relied on people’s own reports about their sleep and eating, which can be less accurate than objective measurements. Also, because this is a cross-sectional study, we can see that sleep and eating habits are connected, but we can’t prove that poor sleep actually causes unhealthy eating—it could work the other way around, or both could be caused by something else.

What the Results Show

The study found clear connections between poor sleep and unhealthy eating patterns. People who reported poor sleep quality were significantly more likely to eat when they were bored, stressed, or angry. They also ate more often, overate more frequently, and chose energy-dense foods (foods high in calories but low in nutrition) more often than people who slept well.

People who slept too little showed similar patterns. They were more likely to skip meals, eat impulsively, and choose unhealthy foods. The strength of these connections was quite strong—for example, people with poor sleep quality were up to 3.5 times more likely to eat out of boredom or stress compared to those who slept well.

Interestingly, people who slept too much (long sleep duration) also showed signs of eating for emotional reasons, but they didn’t show as many signs of eating without thinking or losing control around food. This suggests that both too little sleep and too much sleep can affect eating, but in slightly different ways.

Some eating behaviors didn’t show a clear connection to sleep. For example, adding sugar to food and snacking between meals weren’t consistently related to how much or how well people slept. This suggests that sleep affects some eating behaviors more than others, particularly those driven by emotions and stress rather than simple habits.

Previous research has shown that poor sleep can increase hunger hormones and affect the brain’s reward system, making unhealthy foods more appealing. This study supports those earlier findings by showing that in real life, people with poor sleep actually do eat more unhealthy foods and eat more often for emotional reasons. The study adds important information by showing that these connections exist in a very large, diverse group of real people, not just in controlled research settings.

The main limitation is that all the information came from people’s own reports rather than objective measurements. People might not remember their sleep or eating habits accurately. Additionally, because this study captured a snapshot in time rather than following people over months or years, we can’t determine whether poor sleep causes unhealthy eating or if unhealthy eating causes poor sleep. The study also didn’t measure other factors that might affect both sleep and eating, such as stress levels, mental health, or physical activity. Finally, the study included mostly UK adults, so the results might not apply to people in other countries with different food environments or sleep patterns.

The Bottom Line

If you struggle with overeating or eating unhealthy foods, try to improve your sleep as part of your overall health plan. Aim for 7-9 hours of sleep per night and try to maintain consistent sleep and wake times. If you notice you eat when you’re bored, stressed, or upset, improving your sleep might help reduce these behaviors. However, sleep improvement should be combined with other healthy habits like regular physical activity and stress management. These recommendations are based on moderate evidence from this large study, but more research is needed to prove that improving sleep directly causes better eating habits.

This research is relevant for anyone who struggles with overeating, emotional eating, or maintaining a healthy weight. It’s particularly important for people who know they don’t sleep well or don’t get enough sleep. People with very long sleep durations might also benefit from examining their eating patterns. However, this study doesn’t apply to people with diagnosed sleep disorders who are already receiving treatment—they should follow their doctor’s advice.

You might notice improvements in your eating habits within a few weeks of improving your sleep, but it often takes 4-8 weeks to see significant changes. Some people notice they feel less hungry and have fewer cravings for unhealthy foods within days of sleeping better, while others take longer to adjust.

Want to Apply This Research?

  • Track both sleep duration and quality (rate your sleep quality 1-10 each morning) alongside emotional eating episodes. Log instances when you eat due to boredom, stress, or anger rather than physical hunger. Look for patterns over 2-4 weeks to see if better sleep correlates with fewer emotional eating episodes.
  • Set a specific sleep goal (e.g., 7.5 hours nightly) and use the app to log your actual sleep. When you feel the urge to eat out of boredom or stress, pause and check your sleep log from the previous night. If you slept poorly, acknowledge that your body may be sending false hunger signals and try a non-food coping strategy instead (like a 10-minute walk or drinking water).
  • Create a weekly dashboard showing sleep quality/duration alongside a count of emotional eating episodes. Set reminders to rate sleep quality each morning and log emotional eating moments when they occur. Review weekly trends to identify if specific sleep patterns (e.g., less than 6 hours) consistently precede higher emotional eating days.

This study shows a connection between sleep and eating habits but does not prove that poor sleep causes unhealthy eating. If you have concerns about your sleep, eating habits, or weight, please consult with a healthcare provider or registered dietitian. This information is not a substitute for professional medical advice, diagnosis, or treatment. People with diagnosed sleep disorders should work with their healthcare provider before making changes to their sleep routine.