What is already known
Gut microbes are essential for health, but modern lifestyles have reduced microbial diversity and increased the risk of chronic diseases. Previous research has explored ways to restore the microbiota in industrialized regions, for example by combining a diet similar to that of non-industrialized populations with the introduction of beneficial bacteria.
What this research adds
Researchers gave 30 healthy adults a high-fiber, plant-based diet, along with supplementation of Limosilactobacillus reuteri. The diet increased beneficial bacteria, such as Bifidobacterium and Faecalibacterium, while reducing microbes that have been linked to inflammation. It also improved blood metabolites and cardiometabolic risk markers, such as LDL cholesterol and glucose. However, the effects on gut microbiota composition were specific to each person, and restoring certain microbes, such as L. reuteri, proved challenging.
Conclusions
The findings suggest that dietary interventions can help maintain a healthy gut microbiota.
Gut microbes are essential for health, but modern lifestyles have reduced microbial diversity and increased the risk of chronic diseases. To address these challenges, researchers have developed a new approach to restore the gut microbiota by combining a high-fiber, plant-based diet with supplementation of beneficial microbes such as Limosilactobacillus reuteri.
The findings, published in Cell, suggest that dietary interventions can help maintain a healthy gut microbiota.
Previous research has explored ways to restore the microbiota in industrialized regions, for example by combining a diet similar to that of non-industrialized populations with the introduction of beneficial bacteria. This approach has been tested in a Canadian trial to improve gut health and reduce disease risk.
Building upon this work, researchers led by Fuyong Li at the University of Alberta in Edmonton, Canada, gave 30 healthy adults a “restore diet” to see how it affected their gut microbiotas, metabolism and overall health.
Restoring microbiotas
The restore diet focused on plant-based, high-fiber foods while avoiding processed ones, and participants were also given L. reuteri supplements. Although participants reported no serious side effects, by increasing fiber intake, the diet resulted in softer stools and mild gastrointestinal issues in some people.
Within just two days of L. reuteri supplementation, the bacterium became detectable in the stool of participants, and it was found to survive longer and adapt well to the restore diet. While the diet did reduce gut microbiota diversity, the changes in microbiota composition were specific to each person, and the diet alone explained a small part of these changes. What’s more, restoring certain microbes, such as L. reuteri, proved challenging.
However, the diet did show some positive effects: for example, it increased beneficial bacteria, such as Bifidobacterium and Faecalibacterium, while reducing microbes that have been linked to inflammation.
Disease markers
The restore diet had physiological benefits on the participants, lowering fecal pH and increasing beneficial short-chain fatty acids. These changes were linked to improvements in blood metabolites and cardiometabolic risk markers, such as LDL cholesterol and glucose, the researchers found.
Machine learning models also showed that changes in the microbiota and blood metabolites could predict the diet’s positive effects on health. However, while microbiota composition could help predict changes in cholesterol and inflammation markers, reductions in glucose levels were highly individualized.
The restore diet might benefit metabolic health and help prevent non-communicable diseases such as diabetes. “The findings suggest that a dietary intervention targeted toward restoring the gut microbiome can improve host-microbiome interactions that likely underpin chronic pathologies, which can guide dietary recommendations and the development of therapeutic and nutritional strategies,” the authors say.
