New “Leaky Gut” research is surprising
A recent article published in the scientific journal Science has me thinking about how intimately gut health is related to the other aspects of our physiology.
The researchers used a variety of methods to determine why obesity was correlated with increased intestinal permeability (aka “leaky gut”). Remarkably, they found that obesity itself was NOT correlated with leaky gut EXCEPT when it was associated with high blood glucose levels. Furthermore, high blood glucose levels in the absence of obesity also caused leaky gut, which they defined as the movement of intestinal contents into the blood stream, followed by increases in inflammation. The authors then determined that high blood glucose altered gene expression in the cells lining the intestines, specifically affecting genes important for maintaining the integrity of the cell lining.
Taken together, high blood glucose levels produce a leaky gut by impairing the connectivity between the cells lining the gut, and this leads to systemic inflammation. Given that inflammation is known to cause insulin resistance, it appears that leaky gut contributes to a Catch-22 situation with respect to hyperglycemia: High blood glucose creates a leaky gut, leaky gut leads to inflammation, inflammation leads to insulin resistance and high blood glucose, and the cycle continues.
This remarkable finding inspires new questions: Does high blood glucose affect the expression of genes in other cell types? Might cells in the large intestine prefer butyrate to glucose for energy because glucose has a negative effect on these cells? Could high blood glucose levels impair the healing process, thereby explaining why diabetics are afflicted by slow healing wounds?
The researchers did not test the role of prebiotics in their study, so my post should not be taken as a claim that prebiotics will help restore leaky gut. However, these findings are relevant to anyone interested in gut health.
Ultimately, this research needs to be further validated but it certainly suggests that leaky gut is a physiological reality that occurs in response to high blood glucose, a chronic issue of epidemic proportion. Fortunately, the authors demonstrate that normalizing blood glucose levels helps to restore integrity to the intestinal barrier, meaning that there is an opportunity to interrupt this vicious cycle.