This Habit Could Nearly Double Your Constipation Risk, New Study Suggests
Key Points
We’ve all been there: you finish a stressful workday, dinner gets pushed back and by the time you sit down to eat, it’s well past 9 p.m. But new research suggests this combination—a high-pressure day followed by a late-night meal—may be harming your gut health.
Stress is already known to disrupt bowel function, and recent research has linked late-night eating to digestive symptoms, including constipation. New findings presented at Digestive Disease Week 2026 suggest the combination may pack a bigger punch than either factor alone.
How Was This Study Conducted?
Researchers analyzed data from more than 11,000 adults in the National Health and Nutrition Examination Survey. They looked for links among three things: chronic stress, late-night eating and bowel dysfunction.
To measure stress, they used an allostatic load score—a measure of long-term stress on the body—reflected in markers like body mass index, cholesterol and blood pressure. To flag late-night eating, they identified people who ate more than 25% of their daily calories after 9 p.m.
What Did the Study Find?
People with high allostatic load scores who got more than a quarter of their calories after 9 p.m. were 1.7 times more likely to report constipation or diarrhea than people with lower stress scores who didn’t eat late.
In the American Gut Project data, people with both high stress and late-night eating habits were 2.5 times more likely to report bowel problems than less-stressed early eaters.They also had significantly lower gut microbiome diversity, suggesting meal timing might amplify the effects of stress on the gut microbiome. The researchers point to the gut-brain axis as the likely connection.
“It’s not just what you eat, but when you eat it,” lead author Harika Dadigiri, M.D., said in a press release from Digestive Disease Week. “And when we’re already under stress, that timing may deliver a ‘double hit’ to gut health.”
The research is observational, and the full study has not yet been peer-reviewed. Still, the findings line up with earlier work. In a 2025 study of more than 1,300 adults published in the Journal of Eating Disorders, researchers found that night eating was significantly correlated with gastrointestinal symptoms including constipation. And in a 2026 study of medical students published in the Journal of Family Medicine and Primary Care, researchers found a significant association between higher stress levels and constipation.
How Does This Apply to Real Life?
If you tend to eat dinner late or snack past 9 p.m., especially during stretches of high stress, the takeaway isn’t to introduce more stress by feeling guilty about your last meal. Instead, consider trying some of these common sense ways to put the research into action:
- Try to wrap up your last meal earlier when you can. Aim to finish eating a few hours before bed and shift more of your calories to daylight hours. Dadigiri said small, consistent habits like maintaining a structured meal routine may support digestive function over time.
- Build a steady meal rhythm. Eating at roughly the same times each day can support your circadian rhythm, which plays a role in healthy digestion.4
- Tend to the stress side of the equation. Small habits like a short walk, a few minutes of deep breathing or a consistent bedtime can take the edge off the chronic stress that appears to exacerbate late-night eating’s gut effects.
- Lean on fiber and fluids. Plant foods like beans, vegetables, fruit, nuts and whole grains feed beneficial gut bacteria, and good hydration supports gut health.
Our Expert Take
New research presented at Digestive Disease Week 2026 suggests that combining chronic stress with late-night eating may nearly double your odds of constipation and diarrhea. The findings are preliminary, but they reinforce the idea that meal timing matters, especially when you’re stressed. Shifting your eating to earlier in the day, keeping meal times steady and easing daily stress could help keep your gut on track.