Advances in IBD

Advances in IBD

December 13, 2019
2 min read

Diet as therapy for IBD remains hindered by knowledge gaps

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James D. Lewis, MD, MSCE
James D. Lewis

ORLANDO — As patients with Crohn’s disease seek guidance on how to handle their condition, there remains a knowledge gap regarding what, if any, specific dietary recommendations could become a mainstay therapy, according to a presentation at Advances in Inflammatory Bowel Disease 2019.

“We don’t have enough definitive research to say that one diet is the right answer for patients with Crohn’s disease or ulcerative colitis,” James D. Lewis, MD, MSCE, from the Perelman School of Medicine at University of Pennsylvania, told Healio Gastroenterology and Liver Disease, on the topic of his Rick MacDermott Lecture on diets in inflammatory bowel disease. “However, there is more reason to believe that diet plays an important role in Crohn’s disease based on what we know about the effectiveness of exclusive enteral nutrition for Crohn’s disease.”

Lewis continued that, when looking at whole-food diets, a common theme of diets that have shown some efficacy is the incorporation of fresh ingredients including fruits and vegetables. This is interesting, he said, because many patients are often counseled when diagnosed with Crohn’s to avoid fruits and vegetables.

Among the reasons that diet has yet to become a mainstay therapy for Crohn’s, Lewis pointed to the lack of high-quality data. Performing studies on dietary intervention are particularly difficult, resulting in less than high-quality data to define what a patient should “definitely be doing,” he said.

The second challenge is that following a diet is generally difficult.

“Think about all the different scenarios other than IBD where we advise people to follow a specific diet, such as for weight loss,” Lewis said. “It is hard for people to sustain this over a long period of time. Talk to patients with Celiac disease where they need to follow a gluten-free diet for the rest of their life. What do they all want? They want a medicine that would allow them to eat gluten-containing foods.”

While the optimal type diet remains to be determined, if a patient needed to follow a diet “religiously” every day, every year, that would be much more difficult to maintain than administering a medication at weekly or monthly periods.

“There are a number of more modern clinical trials that are trying to close this gap,” Lewis noted. “I think going forward these trials will open the opportunity to leverage new omics technologies to try and figure out, of those diets that work, why do they work. Then, maybe, we actually get to the little magic pill that does whatever these diets are doing and lets you eat whatever you want, or we find the way to make the diet as manageable as possible.”


Lewis concluded that patients should look for opportunities to find a dietician who is well-trained in caring for patients with IBD and partner with them. He that correcting nutritional deficiencies is an important step.

“We should be particularly cognizant of this in patients who are acutely ill. Even if they don't look malnourished, they may be malnourished,” he said. “You can be normal weight but have compromised nutritional status. This is particularly important for those who may be moving toward surgery. It’s really important to work to get them nutritionally replete, most of the time using their gut as opposed to parenteral nutrition. These are basic principles that have known for decades; we should not forget them.” – by Talitha Bennett

Reference: Lewis JD. Rick MacDermott Lecture in Advanced and Multidisciplinary Care in IBD: Diet, the Microbiome, and IBD: “Doctor, What Should I Eat for My IBD?” Presented at: Advances in Inflammatory Bowel Disease; Dec. 12-14, 2019; Orlando.

Disclosure: Lewis reports he received research funding and served as a consultant for Nestle Health Sciences.