Spinach, almonds, sweet potatoes and other foods high in oxalates may intensify gut inflammation in people with Crohn's disease and ulcerative colitis, according to researchers at the University of North Carolina. The findings were published in the journal Cellular and Molecular Gastroenterology and Hepatology.
The team examined tissue and stool samples from patients with inflammatory bowel disease and ran additional experiments on mice and cell cultures. They found that in affected patients, the activity of proteins responsible for clearing oxalates from the body was significantly reduced.
What are oxalates
Oxalates are naturally occurring compounds found in many plant-based foods, including leafy greens, nuts and certain root vegetables. When the body cannot clear them efficiently, the researchers said, oxalates build up in the gut and, according to their experiments, drive a stronger inflammatory response.
Animal testing supported the finding. Mice with colitis that were fed a diet high in oxalates had a 60 percent lower survival rate and experienced more severe disease than those on a standard diet, the researchers reported.
The team also found that certain disruptions in how the body excretes oxalates may be linked to a more aggressive course of Crohn's disease.
Not a call to cut out these foods
The study's authors stressed that the results do not mean patients with inflammatory bowel disease need to eliminate spinach, nuts or other plant foods from their diets entirely. They suggested the issue is not simply about how much oxalate a food contains, but about how an individual person's body processes it.
Crohn's disease and ulcerative colitis are both forms of inflammatory bowel disease, a group of chronic conditions in which the immune system triggers ongoing inflammation of the digestive tract. Symptoms can include abdominal pain, diarrhea and fatigue, and severity varies widely between patients.
The researchers previously found that compounds in leafy vegetables can help protect against cardiovascular disease.
