According to Gram Research analysis, eating large meals late at night and being a natural night owl are both linked to worse sleep quality in adults, while eating melatonin-rich foods showed no benefit for sleep after accounting for other factors. A 2026 cross-sectional study of 325 adults found that night eating scores strongly predicted poor sleep quality (correlation of 0.537), and evening-type people slept worse than morning types, but dietary melatonin intake was not associated with sleep quality.
A new study of 325 adults found that eating late at night and being a natural night owl are linked to worse sleep quality, but eating foods with melatonin didn’t help much. Researchers in Turkey tracked what people ate, their sleep habits, and whether they were morning people or night people. The study suggests that when you eat and your natural sleep schedule matter more for good sleep than simply eating melatonin-rich foods. However, the researchers say more long-term studies are needed to prove these connections work the same way over time.
Key Statistics
A 2026 cross-sectional study of 325 Turkish adults found that people who ate more at night had significantly worse sleep quality, with a strong correlation of 0.537 between night eating scores and poor sleep.
According to the same 2026 study, evening-type people (night owls) had worse sleep quality than morning types, with a correlation of -0.159, but dietary melatonin intake averaged only 10.5 micrograms per day and showed no association with sleep quality.
The 2026 study identified a significant indirect pathway where being a night person led to eating more at night, which then resulted in poorer sleep quality, suggesting these factors work together to affect sleep.
The Quick Take
- What they studied: How eating melatonin-containing foods, being a night person versus morning person, eating late at night, and sleep quality are all connected to each other
- Who participated: 325 adults between ages 18 and 65 living in Istanbul, Turkey, studied between November 2024 and June 2025
- Key finding: People who eat more at night had worse sleep quality, and night owls slept worse than morning people. Surprisingly, eating melatonin-rich foods didn’t improve sleep when other factors were considered.
- What it means for you: If you’re a night person who eats late, you might sleep better by eating your main meals earlier in the day. However, this is one study, so talk to a doctor before making big changes to your eating schedule.
The Research Details
This was a cross-sectional study, which means researchers took a snapshot of 325 people at one point in time rather than following them over months or years. Participants answered detailed questionnaires about their sleep quality using a standard tool called the Pittsburgh Sleep Quality Index, which asks about how well and how long they sleep. They also completed surveys about whether they’re naturally morning people or night people, and whether they eat large meals late at night. Researchers estimated how much melatonin people ate by looking at a food frequency questionnaire that listed foods known to contain melatonin, like nuts, seeds, and certain fruits.
The researchers used statistical methods to look for connections between these different factors. They checked whether people who ate more melatonin slept better, whether night owls had different sleep patterns than morning people, and whether eating late at night affected sleep quality. They also looked at whether being a night person led to eating more at night, which then caused worse sleep.
This type of study is good for finding patterns and generating new ideas for research, but it can’t prove that one thing causes another because everything was measured at the same time.
Understanding how eating timing, natural sleep preferences, and sleep quality connect is important because many people struggle with sleep. If researchers can identify which factors matter most, doctors and nutritionists can give better advice. This study helps narrow down whether the solution is eating specific foods with melatonin or whether changing when you eat might be more helpful.
The study included a reasonable number of participants (325) and used validated, well-established questionnaires that are used in sleep research worldwide. However, because it’s cross-sectional, it only shows associations, not cause-and-effect relationships. People self-reported their eating and sleep habits, which can be less accurate than objective measurements. The study was conducted in one city in Turkey, so results might not apply equally to all populations. The researchers were honest about these limitations and called their findings ‘hypothesis-generating,’ meaning they’re ideas for future research rather than definitive answers.
What the Results Show
The average person in the study ate about 10.5 micrograms of melatonin per day from food. People who ate more at night had significantly worse sleep quality, the connection was strong (correlation of 0.537). Night owls had worse sleep quality than morning people, with a moderate connection (correlation of -0.159). When researchers looked at all factors together using statistical models, eating more at night remained strongly linked to worse sleep, and being a night person was linked to worse sleep.
Interestingly, the amount of melatonin people ate from food was not connected to sleep quality once the researchers adjusted for other factors like age, body weight, and exercise. This was surprising because melatonin is often promoted as a sleep aid. The researchers found that being a night person was connected to eating more at night, and eating more at night was connected to worse sleep, suggesting these factors work together.
The study identified what’s called an ‘indirect association,’ meaning that being naturally inclined to be a night person might lead to eating more at night, which then leads to worse sleep. This chain of connections was statistically significant, suggesting it’s a real pattern rather than random chance.
The study found that chronotype (whether you’re a morning or night person) and night eating behaviors together explained sleep quality better than looking at either factor alone. This suggests that your natural sleep preference and when you eat work together to affect how well you sleep. The researchers also noted that dietary melatonin intake varied widely among participants, ranging from very small amounts to much larger amounts, but this variation didn’t predict sleep quality differences.
Previous research has shown that melatonin supplements can help some people sleep better, but this study suggests that eating melatonin-containing foods might not have the same effect. The finding that eating timing and chronotype matter more than melatonin content aligns with growing research in ‘chrononutrition’, the idea that when you eat matters as much as what you eat. This study adds to evidence that night eating is associated with sleep problems, which has been shown in other research as well.
This study is cross-sectional, meaning it’s like taking a photograph rather than a video: it shows what’s happening at one moment but can’t prove what causes what. People reported their own eating and sleep habits, which might not be perfectly accurate. The study was done in one city in Turkey with mostly one population, so results might be different in other countries or cultures. The researchers didn’t measure actual melatonin levels in people’s blood, only estimated intake from food. Finally, the study can’t tell us whether changing eating times would actually improve sleep, only that eating times and sleep quality are connected.
The Bottom Line
If you’re a night person who eats large meals late in the evening and you struggle with sleep, consider eating your main meals earlier in the day. This is a moderate-confidence recommendation based on this one study. Eating melatonin-rich foods like almonds, walnuts, or tart cherry juice probably won’t hurt, but this study suggests they won’t dramatically improve sleep on their own. If sleep problems persist, talk to a doctor or sleep specialist.
Anyone who eats significant amounts of food late at night and has poor sleep should pay attention to this research. Night owls who struggle with sleep might benefit most from trying to eat earlier. People considering melatonin supplements should know that eating melatonin-containing foods alone may not be enough. This research is less relevant for people who naturally sleep well or who eat most of their food during the day.
If you change your eating schedule, you might notice sleep improvements within 1-2 weeks, though it can take 4-6 weeks for your body to fully adjust to new eating times. Don’t expect overnight changes, sleep patterns take time to shift.
Frequently Asked Questions
Does eating melatonin-rich foods like almonds and cherries actually help you sleep better?
A 2026 study of 325 adults found that dietary melatonin intake was not associated with sleep quality after accounting for other factors. While melatonin supplements may help some people, eating melatonin-containing foods alone probably won’t significantly improve sleep.
Why do night owls sleep worse than morning people?
This study found that evening-type people had worse sleep quality, and part of the reason may be that they tend to eat larger meals later at night. Night owls who eat earlier in the day might sleep better, though more research is needed to confirm this.
What time should I stop eating to sleep better?
This study suggests eating your main meals 3-4 hours before bedtime may improve sleep quality, especially if you’re naturally a night person. However, this is one study, so individual results vary. Experiment with your own schedule and track your sleep to find what works for you.
Can changing when I eat fix my sleep problems?
This study shows eating timing is connected to sleep quality, but it can’t prove that changing when you eat will fix sleep problems. It’s worth trying to eat earlier if you eat late at night, but if sleep problems persist, see a doctor to rule out other causes.
Is this study proof that night eating causes bad sleep?
No, this is a cross-sectional study that shows associations, not cause-and-effect. It found that night eating and poor sleep are connected, but researchers need long-term studies to prove that eating late actually causes worse sleep.
Want to Apply This Research?
- Log your meal times and sleep quality daily for 4 weeks. Note what time you finish eating and rate your sleep quality the next morning on a scale of 1-10. Look for patterns between earlier meal times and better sleep scores.
- Set a ’eating cutoff time’ 3-4 hours before your target bedtime. Use the app to send reminders when this time approaches, and track how many days you stick to it. Gradually move your dinner time earlier by 15-30 minutes each week.
- Create a weekly sleep quality average and compare it to your average meal time. Track whether moving meals earlier correlates with better sleep over 4-8 weeks. Also note your natural wake time to confirm your chronotype, and see if night owls benefit more from earlier eating times than morning people.
This research is observational and cross-sectional, meaning it shows associations but cannot prove cause-and-effect relationships. These findings should not replace professional medical advice. If you have persistent sleep problems, night eating behaviors, or are considering melatonin supplements, consult with a healthcare provider or sleep specialist. This study was conducted in Turkey and may not apply equally to all populations. Individual results vary, and what works for one person may not work for another.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.
