Everything You Need to Know About Fiber and Crohn's Disease, According to Dietitians

What you eat can make a difference in how you feel. Here’s how to find foods that work for your gut.crohns diseaseGQ; Getty ImagesJust thinking about fiber can make many people with Crohn’s feel nervous. After all certain fiber-rich foods can be tough to tolerate, but the ones that cause trouble aren’t always obvious. Even a seemingly harmless omelet or a fruit smoothie can trigger symptoms in some people. So if you’ve been avoiding the nutrient, that’s understandable—and not uncommon. Research suggests people with Crohn’s tend to eat relatively little fiber, even during remission. One 2015 study found the average daily intake for individuals with the condition was just 16 grams. For context, experts recommend that men aim for 38 grams a day.But here’s the thing: Having an inflammatory bowel disease doesn’t necessarily mean you should stick to a low-fiber diet. Some studies have found that eating foods rich in the nutrient may actually lower your risk of future flares, improve gut health, and reduce inflammation not only in your gastrointestinal tract but throughout your body.We get it, though—navigating the sometimes confusing and land-mine-filled world of fiber can feel overwhelming, especially post-flare, and the stakes are high. No one wants to feel crummy or worry about being stuck near a toilet all day. That’s why we asked a group of registered dietitians to answer some of the most pressing questions about Crohn’s and fiber. Here’s what they said about getting enough without upsetting your stomach, which types may be harder to tolerate, and more.What is fiber, and why do you need it?Let’s take a step back and review some nutrition science 101.In the simplest terms, fiber is a plant-based carbohydrate our bodies cannot fully breakdown or absorb. It resists digestion in the stomach and small intestine and depending on the type, is either partially or fully fermented by gut bacteria in the colon. This makes it different from other nutrients like fats and proteins, which the body breaks down and absorbs.There are two main types of fiber, each with its own functions and benefits. Here’s a quick overview of each:Insoluble fiberWhat it is: A type of fiber that passes through the GI tract largely intact, adds bulk to stools, helps keep you regular, and aids in regulating blood sugar. Foods rich in insoluble fiber are typically the ones we think of as hard to digest.Where to find it: Pear and apple skins, raspberries, wheat bran, leafy greens like kale and collard greens, nuts, seeds, and legumes, among other foods.Soluble fiberWhat it is: A type of fiber that dissolves in water and forms a gel in the gut, slowing carbohydrate absorption. It helps control cholesterol, increases satiety, and makes stools easier to pass.Where to find it: Beans, oats, barley, carrots, and the flesh of pears, among other foods.Can you eat fiber during a Crohn’s flare?The short answer: yes. But proceed with caution. During an active flare your fiber intake should depend on what you can tolerate, with amounts gradually increasing as symptoms improve.“The goal is not to eat as much fiber as possible,” says Anya Argosh, MS, RD, a registered dietitian and the founder of Birchwell Clinic. “It’s to build as much dietary variety as your gut can comfortably and safely handle.”A lower-fiber diet is often recommended during flares to give the GI tract a “rest.” However, Dahlia Marin, RDN, LD, CGN, a registered dietitian specializing in GI issues and co-founder of Married to Health, says limited evidence supports this approach for people without strictures (abnormal narrowings in the GI tract). “Historically, people with active Crohn’s were often told to follow a low-fiber diet, particularly when experiencing diarrhea, abdominal pain, or increased bowel movements. However, current research does not strongly support eliminating all fiber during a flare,” Marin says.Instead, Marin recommends tailoring food choices to your symptoms and tolerance.For example, if certain textures are hard for your body to handle, changing how you prepare foods may help.Consider “choosing well-cooked, peeled, blended, or puréed fruits and vegetables rather than large amounts of raw, fibrous foods,” she says. That might mean roasting carrots or pears instead of eating them raw in a salad or opting for puréed vegetable soup or smoothie.During a flare foods high in insoluble fiber—such as fruit and vegetable skins, fibrous leafy greens, nuts, seeds, popcorn, and corn on the cob—may also need to be temporarily limited until symptoms improve.If you have a stricture, eating softer foods or modifying textures, limiting sources of insoluble fiber, and chewing thoroughly are especially important to help reduce the risk of an obstruction. However, fiber tolerance varies from person-to-person and if you have a stricture, you should work with your healthcare provider to come up with an individualized plan.Kelly L. Burgess, MBA, RD, LDN, the founder of To Better Health LLC and the creator of the HealthyBites HealthyLife app, says she sometimes suggests a low-FODMAP diet during an active flare. This short-term approach may help people whose symptoms are triggered by FODMAPs, fermentable carbohydrates that can be hard on the gut. High-FODMAP foods include certain beans and legumes, as well as vegetables such as cabbage, cauliflower, garlic, and onions, which can cause symptoms like gas and bloating in some people.A low-FODMAP diet is typically used on a temporary basis in people with irritable bowel syndrome (IBS) to identify symptom triggers and may help relieve symptoms in people with Crohn’s who have IBS-like symptoms.How can you safely increase your fiber intake with Crohn’s?Whether you’re coming off a flare or in remission, it’s best to take a “low and slow” approach to adding more fiber to your diet, Argosh says. Introducing too much too quickly can worsen symptoms, leaving you bloated and uncomfortable. “Pace your fiber—don’t force it,” Burgess says. “Begin with small amounts and increase them gradually as tolerated.” In practice, this might mean starting with small portions of well-tolerated fiber-rich foods spread throughout the day, then gradually expanding the types and amounts of fiber you eat at meals and snacks.Some experts suggest a multi-step approach, starting with easy-to-tolerate, soft fruits, veggies, and grains—think potatoes, white rice, and bananas—and gradually progressing to harder-to-digest salad, seeds, corn, celery and dried fruit.It’s worth noting that hydration should also increase as fiber intake rises to soften stools and prevent constipation.Should you take a fiber supplement?When it comes to getting fiber, the dietitians agree that food is generally the best place to start. Fruits, vegetables, whole grains, and other plant foods offer more than just fiber—they also provide other vitamins, minerals, and antioxidants that support overall health and may help with inflammation.That said fiber supplements can sometimes come in handy, especially when you’re traveling or don’t have access to the foods you typically eat. Finding one that works for you may take some patience, though.Marin says different supplements can affect your gut in very different ways. “For example, psyllium is a soluble, gel-forming fiber that holds water but is not heavily fermented, while fibers such as inulin and fructooligosaccharides are much more fermentable and can have a greater effect on the gut microbiome.” In practical terms these variations mean one supplement might sit just fine with you and another could leave you feeling gassy or bloated. Which brings us to…When should you see a dietitian or doctor?If you’re having trouble eating enough, losing weight without trying, finding yourself cutting out more and more foods, or feeling unsure how to add fiber into your diet after a flare, consider seeing a registered dietitian who specializes in inflammatory bowel disease (IBD). These professionals can help you get the nutrients you need while figuring out which foods and textures work best for you so you don’t unnecessarily restrict your diet. They can also check for nutrient deficiencies and help tailor your diet if you have a stricture, have had surgery for Crohn’s, or are dealing with other Crohn's complications.A registered dietitian can also help you identify your trigger foods. Triggers generally vary from person to person, which can make them tricky to pin down. Some people tolerate oats and nuts, while others can’t eat either. The same goes for raw fruit and veggies, whole grains, and other fiber-containing foods. It comes down to trial and error: figuring out what works for you—and what doesn’t.Your gastroenterologist should be involved if you have new or worsening symptoms, particularly if you’re experiencing persistent abdominal pain, frequent diarrhea, blood in your stool, unexplained weight loss, worsening fatigue, and/or vomiting. Get urgent medical attention if you have severe abdominal pain, repeated vomiting, abdominal swelling, or can’t pass stool or gas. These can be signs of an intestinal obstruction, which is especially important to watch for in people with Crohn’s-related strictures.Not a subscriber? Join GQ to receive full access to GQ.com.Edwina Clark is a nationally recognized registered dietitian, dual-credentialed in the US and Australia, and a certified specialty sports dietitian. ... Read More