Healthy Plant Foods Can Worsen IBD Symptoms, New Study Reveals
A new UNC study reveals that healthy plant foods like spinach and almonds can worsen IBD like Crohn's and colitis due to impaired oxalate absorption proteins in the gut.
Healthy Foods Can Exacerbate Bowel Inflammation
Some of the foods considered the healthiest—including spinach, almonds, and sweet potatoes—may worsen intestinal inflammation in patients dealing with inflammatory bowel diseases (IBD), such as Crohn's disease and ulcerative colitis. This is according to a new study conducted at the University of North Carolina (UNC) and published in the scientific journal Cellular and Molecular Gastroenterology and Hepatology.
According to the researchers, the culprit behind this phenomenon is oxalate, a natural compound found in plant-based foods. While it is mostly known as a cause of kidney stones, scientists point out that oxalate remaining in the digestive system can increase intestinal inflammation.
The Problem: Digestive System Failure, Not Diet
The research team, led by Dr. Anna Salvador and Prof. Shehzad Sheikh, found that in patients with Crohn's disease (a chronic inflammatory bowel disease) and ulcerative colitis (an inflammatory bowel disease primarily concentrated in the large intestine), there was a decrease in transport proteins—proteins responsible for transporting substances across cell membranes—named SLC26A2 and SLC26A3. The scientists explained that these proteins are responsible for absorbing oxalate, and when their levels drop, oxalate remains in the intestine and intensifies the response of immune system cells that damage the intestinal lining.
According to the researchers, Crohn's patients exhibited high levels of oxalate in their stool compared to healthy individuals, even though both groups consumed a similar amount of plant-based food.
"This showed us that it's not just about what the patients are eating, but that there is something fundamentally different in the way their intestine handles oxalate," explained Dr. Salvador.
In animal experiments, an oxalate-rich diet even worsened the disease and reduced the survival chances of mice with intestinal inflammation by 60%.
Do Not Stop Eating Vegetables
Despite the findings, the scientists emphasize that this is not a recommendation to eliminate plant-based foods from the diet, as they are essential for health, and a low-oxalate diet can be formulated.
In the future, researchers estimate that it will be possible to incorporate treatments based on gut bacteria, giving the example of the bacterium Oxalobacter formigenes, which breaks down oxalate and is found at low levels in patients. By doing so, they say, inflammation can be reduced without compromising nutritional diversity.
"For patients living with Crohn's or ulcerative colitis, this study opens up a completely new therapeutic angle, connecting the food on the plate to the inflammation in the intestine," concluded Prof. Sheikh. "Nutrition is one of the most powerful and accessible tools we have in medicine, and this study gives us the precise scientific explanation for the first time so we can use it in a personalized way."
