Eating diets low in fat and high in fiber may improve the quality of life of patients with ulcerative colitis (UC) — even those in remission.

That’s the finding of a study published in Clinical Gastroenterology and Hepatology led by Maria T. Abreu, M.D., professor of medicine and professor of microbiology and immunology at the University of Miami Miller School of Medicine.

“Patients with inflammatory bowel disease always ask us what they should eat to make their symptoms better,” said Dr. Abreu. “Sadly, there have been very few really good studies that provide that information.”

Dr. Abreu’s work is changing that.

The current study looked at 17 people with UC, a type of inflammatory bowel disease (IBD) that can cause a number of symptoms, including bloody diarrhea, abdominal cramps and pain. Each participant’s UC was either in remission or considered mild, with relatively little diarrhea, bleeding, or pain.

• One group ate a diet high in fiber, fruits, and vegetables and low in fat, with just 10% of calories from fat.
• The second group ate a diet that included higher quantities of fruits, vegetables and fiber than a standard American diet. About 35% to 40% of their calories came from fat.
• Participants then changed to the opposite diet for the next four weeks.

All foods were catered and delivered to participants’ homes.

Researchers looked at the participants’ pre-study diets and used questionnaires to measure their quality of life based on their physical, social and emotional well-being. The questionnaires were given at the study’s start and four weeks after being on each diet. Participants also underwent blood and stool tests during the same period to look for markers of inflammation and to check the balance of their gut bacteria and metabolites, something that can impact digestive health.

“The results were fascinating and show us how poorly patients eat at baseline,” said Dr. Abreu, who is also director of the University of Miami Health Systems Crohn’s and Colitis Center.

Perhaps more important, they showed that improving one’s diet could improve their overall well-being. Both the low-fat and high-fat diets had more fruits and vegetables and fiber than the patients’ baseline diets. Both study diets were well tolerated and resulted in better quality of life for the study subjects compared to baseline diets, which were significantly unhealthier. However, on the low-fat diet, participants also had lower levels of inflammation and signs of improvement in bacterial imbalance in the gastrointestinal tract. Sadly, many patients with ulcerative colitis are told to avoid fruits and vegetables, which seem to be very beneficial.

The findings suggest that dietary interventions could benefit patients with UC in remission and, perhaps, other forms of IBD as well.

“We are now testing a similar diet in Crohn’s disease patients but adding a psychological component to help with long-term adherence to a healthy diet,” said Dr. Abreu.

Dr. Abreu’s new study, funded by the Helmsley Charitable Trust, will involve 160 patients with Crohn’s disease over the next three years.