Intense Exercise May Alter Gut Microbiota, Gut Health
Human intestines are semi-permeable, allowing nutrients into the bloodstream and keeping harmful bacteria out. A recent study suggests that physical stress may increase intestinal permeability by changing the microbiota of the gut.
Participants in the study included 73 Norwegian Army soldiers who skied approximately 31 miles over four days while carrying 99-pound packs. The researchers collected blood and stool samples before and after the ski trip. Additionally, the soldiers took 24-hour urine tests before the trip and on the third day, before drinking a solution of water mixed with the artificial sweetener sucralose and the sugar alcohol mannitol. Levels of sucralose are considered a good marker of intestinal permeability because the human body does not break it down during digestion.
At the conclusion of the trip, the soldiers had significant increases in sucralose excretion. They also had higher concentrations of products of bacterial metabolism of amino acids and fat in their stool. The researchers found that changes in intestinal permeability were associated with changes in inflammation, intestinal microbiota composition, and metabolites believed to be derived from the changes in microbiota.
They noted that the findings suggest that changes in intestinal microbiota may be one mediator of intestinal permeability responses to severe physiologic stress. They suggest that targeting the microbiota before stress exposure may help maintain intestinal permeability.
Researchers from U.S. Army Research Institute of Environmental Medicine led the study. It was published online ahead of print on March 23, 2017, in the American Journal of Physiology: Gastrointestinal and Liver Physiology.
Having a varied composition of bacteria in your digestive system is essential for good gut health and for good health overall. Previous studies have linked healthy gut bacteria with strengthening the immune system, better gum health, weight loss, and reducing the risk of chronic disease.