Link Between Healthy Foods and Inflammatory Bowel Disease
New research suggests that some of the healthiest plant-based foods—such as spinach, beetroot, rhubarb, almonds, and sweet potatoes—might be associated with inflammatory bowel disease (IBD).
This study, conducted by a team from the University of North Carolina, centers on a natural compound in plant foods called oxalate.
Oxalate doesn’t serve much purpose in the human body and is typically excreted as waste. However, the findings indicate that for some individuals, difficulties in processing this compound could contribute to gut problems.
The study, published in Cellular and Molecular Gastroenterology and Hepatology, evaluated oxalate levels in participants’ diets and correlated them with stool samples. Different analysis methods were employed across 46 participants, including those with Crohn’s disease (CD), one of the two primary types of IBD.
“For the first time, we observed that IBD patients and healthy individuals consumed similar amounts of plant-based foods, yet CD patients had higher oxalate levels in their stool,” notes gastrointestinal biologist Anna Salvador from the University of North Carolina. “This indicates that the issue isn’t solely about dietary habits; there’s a fundamental difference in how their guts manage oxalate.”
The researchers explored transporter proteins, SLC26A2 and SLC26A3, which are responsible for oxalate absorption in the gut. In tissue samples from individuals with CD, ulcerative colitis, and healthy controls, they found these genes to be less active in IBD cases.
Another part of the study involved tests on mice with induced gut inflammation, mimicking IBD conditions. Results showed that mice receiving additional oxalate experienced worse outcomes: they lost more weight, sustained higher levels of intestinal inflammation for longer periods, and had lower survival rates.
The team’s experiments also measured mouse immune cells’ responses to oxalate. The compound appeared to enhance the inflammatory response, indicating that the connection between oxalate and IBD may stem more from immune reactions than direct damage.
“These findings highlight dietary oxalate as a potentially adjustable factor in intestinal inflammation, emphasizing the importance of considering variations in dietary exposure and oxalate metabolism in inflammatory bowel diseases,” the researchers stated in their published work.
Future research could focus on targeting the SLC26A2 and SLC26A3 transporter proteins, aiming to ensure oxalate is efficiently removed from the gut to prevent harmful buildups.
Additionally, the scientists studied a third transporter protein, SLC26A6. Analysis of 131 Crohn’s disease patients found that a less active SLC26A6 gene was associated with more severe disease manifestations.
“For those living with Crohn’s disease or ulcerative colitis, this research presents a genuinely novel treatment avenue,” says geneticist Shehzad Sheikh from the University of North Carolina. “It links the food they eat to the inflammation in their intestines.”
It’s widely acknowledged that diet influences IBD along with several other critical factors. The researchers are not advocating for the elimination of these foods but suggest that moderating oxalate intake could be beneficial.
Eventually, supplements promoting bacteria that help the body eliminate oxalate might be considered in IBD treatment strategies. Larger participant studies are expected to yield more insights into these mechanisms and identify those who may be more susceptible to oxalate.
“Diet remains one of the most impactful and adjustable tools available in medicine, and this study provides a molecular framework to utilize it more accurately,” Sheikh remarks.
The research has been published in Cellular and Molecular Gastroenterology and Hepatology.
