Late-Night Eating and Sleep Patterns Linked to Leaky Gut and Higher Metabolic Risk in Adults Living With Obesity

Key Takeaways: 

• Adults living with obesity who tend to stay up later and eat later in the day were significantly more likely to show traits associated with metabolic syndrome, with the greatest risk seen in those who combined a late chronotype with late-night eating.
  
• Individuals with higher metabolic risk showed signs of “leaky gut”, in which substances normally kept inside the intestines enter the bloodstream, where they can trigger inflammation and affect other parts of the body.
  
• Participants whose gut barrier function improved after a microbiome-targeted intervention showed an increase in beneficial short-chain fatty acid-producing bacteria, suggesting the microbiome may be a modifiable pathway connecting circadian behaviours and metabolic health.
  
  
  

When we eat may matter as well as what we eat

A new study led by UTHealth Houston has identified a link between late-night eating and sleeping habits, gut health and metabolic disease, offering new insights into why some people living with obesity may face a risk of inflammation and related health problems.

The findings were published in iScience. The research was led by Faraz Bishehsari, MD, PhD, professor and director of the Gastroenterology Research Center in the Department of Internal Medicine at McGovern Medical School at UTHealth Houston.

“We have long recognized the importance of what we eat for metabolic health, but we are increasingly learning that when we eat may also matter. What makes this study interesting is that it connects circadian behaviors with the gut microbiome, intestinal barrier function, and systemic inflammation.

“We wanted to take these findings beyond the clinical setting and examine how eating patterns and their relationship to sleep affect people in their everyday lives,” said Dr Bishehsari.

Night owls, early birds and metabolic syndrome

The researchers analysed how circadian behaviours, including sleep and meal timing, relate to metabolic health in adults with obesity. They looked at two aspects of circadian behaviour: chronotype, which reflects whether someone naturally prefers to wake up early or stay up late, and the timing of food intake.

Adults with obesity who tend to stay up later and eat later in the day were significantly more likely to exhibit traits associated with metabolic syndrome – a group of conditions that increase the risk of heart disease, stroke and type 2 diabetes.

Participants with a later chronotype, often described as “night owls”, were more likely to have a higher number of metabolic syndrome risk factors than those with an early chronotype, or “early bird”. The greatest metabolic risk was observed among individuals who combined a late chronotype with late-night eating habits.

The findings suggest that a mismatch between the body’s internal clock and daily behaviours may contribute to disease risk through changes in the gut microbiome and the intestinal barrier.

Signs of a “leaky gut” and inflammation

Because the gut plays an important role in digestion and overall health, the researchers examined its involvement further. They created a “Metabolic-Inflammatory Score” to understand how the body responds to immune and metabolic changes.

Their findings suggest that individuals with higher metabolic risk showed signs of “leaky gut”, which allows substances that are normally kept inside the intestines to enter the bloodstream. When this happens, those substances can trigger inflammation and affect other parts of the body.

“We know that what we eat matters for our health, but our findings suggest that when we eat is also important. One intriguing possibility is that the gut microbiome and intestinal barrier help explain how disruptions in our daily biological rhythms are connected to metabolic inflammation,” Bishehsari said.

The gut microbiome as a modifiable pathway

The researchers also explored whether improving the gut microbiome could help strengthen the intestinal barrier. Participants who demonstrated improvements in gut barrier function following a microbiome-targeted intervention showed an increase in beneficial short-chain fatty acid-producing bacteria.

This suggests that the microbiome may represent a modifiable pathway connecting circadian behaviours and metabolic health.

According to the study, the findings reflect how late sleep schedules and late-night eating contribute to changes in the gut microbiome, weakening the intestinal barrier and promoting inflammation associated with metabolic disease.

What this could mean for prevention and care

Because sleep and meal timing are behaviours that can potentially be changed, the researchers see scope for new approaches to metabolic disease.

“Because meal timing and other circadian behaviors are potentially modifiable, understanding these relationships could open new opportunities for preventing or managing metabolic diseases through lifestyle changes and interventions targeting the gut microbiome,” Bishehsari said.

As modern lifestyles increasingly challenge natural sleep and eating rhythms, the findings highlight the potential importance of considering not only diet quality but also meal timing and sleep habits when addressing obesity and metabolic disease risk.

Helping people with questions of diet and eating patterns draws on a solid grounding in nutrition and weight management – the focus of professional training such as the College of Contemporary Health’s Nutrition & Weight Management Essentials, a CPD-accredited online short course.

Further studies will be needed to establish whether acting on these pathways improves health outcomes.

“Future research will help determine whether therapies aimed at improving circadian alignment or strengthening the gut microbiome can reduce inflammation and lower the risk of metabolic disease,” Bishehsari said.

About the research team

Bishehsari is the Atilla Ertan, MD, Chair in Gastroenterology Research at McGovern Medical School, as well as a faculty member at The University of Texas MD Anderson Cancer Center UTHealth Houston Graduate School of Biomedical Sciences.

Other UTHealth Houston researchers on the study are Xiangsheng Huang, PhD; Connor Cheek, PhD; and Mahboobeh Mahdavinia, MD, PhD. Additional authors include Edena Khoshaba, MD; Ankur Naqib, PhD; Maliha Shaikh, MS; and Ali Keshavarzian, MD, with Rush University Medical Center, as well as Mohamed Abdel-Mohsen, PhD, with Northwestern University, and Heather Rasmussen, PhD, with University of Nebraska.

CCH insight

This study adds meal timing and sleep habits to the factors worth considering alongside diet quality when supporting people living with obesity. CCH’s Nutrition & Weight Management Essentials CPD short course (10 CPD hours, fully online, CPD-accredited) gives healthcare professionals a solid grounding in the fundamentals of nutrition and the practical methods that help patients achieve and sustain a healthier weight.

Explore Nutrition & Weight Management Essentials →

Source: iScience