Dietary plans are important for managing Crohn’s disease. Some people may benefit from reducing dietary fiber intake. Fiber can be hard to digest and may aggravate symptoms, especially during a flare.

Although dietary factors cannot cure or cause Crohn’s disease, they can affect its symptoms, especially during a flare.

Doctors recommend that people with inflammatory bowel disease (IBD) follow a diet with a reduced fiber intake. However, it is important to consider that some types of fiber may benefit people with IBD.

This article explores the different types of dietary fiber and their effects on Crohn’s disease. It also discusses what foods to eat and avoid, and what supplements to consider taking.

Oats falling onto a surfaceShare on Pinterest
Xvision/Getty Images

Crohn’s disease is a form of IBD. It is a long-term condition that causes irritation and inflammation of the digestive tract.

The disease commonly affects the beginning of the large intestines and the lower part of the small intestines (ileum). However, it can affect any part of the digestive tract, from the mouth to the anus.

About 3 million adults in the United States had the condition in 2015, with this figure having risen significantly over the last couple of decades.

The exact cause of Crohn’s disease is unknown, but experts believe that the condition results from an abnormal immune response.

Diet and nutrition play a significant role in controlling IBD symptoms, yet there is no single diet that works for everyone.

No evidence suggests that any particular food or diet can cause, prevent, or cure Crohn’s disease. However, many doctors recommend a low fiber, or “low-residue,” diet.

Fiber is a substance that remains undigested as it passes through the small intestine. It is present primarily in plant foods, such as fruits, nuts, grains, and vegetables.

Different types of dietary fiber affect digestion in different ways. There are two main types of dietary fiber: soluble and insoluble.

Learn more about soluble and insoluble fibers.

Soluble fibers

These fibers dissolve in water, which helps absorb the water in the gut. This slows the transit time of food through the gut. Soluble fiber takes on a gel-like consistency during digestion, which helps reduce diarrhea and delays the emptying of the intestine, especially during flares.

Insoluble fibers

These types of fibers do not dissolve in water but pool it into the gut. As a result, they move more quickly through the gut and are more difficult for the body to digest. They may aggravate symptoms and cause diarrhea, pain, and bloating. Insoluble fiber can also block the intestinal tract when there is severe inflammation or narrowing of the intestines, known as strictures, during flares.

Learn more about Crohn’s disease and strictures.

Many studies actually report that avoiding fiber may not benefit people with Crohn’s disease.

A 2015 study found that people with Crohn’s disease who did not avoid high fiber foods were approximately 40% less likely to have a flare than those who did avoid them.

Another 2015 study found that a plant-based diet effectively reduced gut inflammation and promoted the overall health of people with IBD.

However, the study authors mention that a low residue diet without insoluble fibers might accelerate an imbalance of microorganisms in the gut, called dysbiosis. They conclude that high amounts of dietary fiber are not harmful to people with IBD but instead seem favorable.

Other research has also explored the benefits of consuming fiber and the lower likelihood of developing Crohn’s disease. A 2017 study found that a high fiber diet may reduce a person’s risk of developing the condition.

Below are some examples of high fiber foods under different categories of food type:

Grains and seeds




Foods to avoid

Most foods contain both types of dietary fiber. Conventionally, doctors advise people experiencing symptoms such as bloating and diarrhea to avoid insoluble fibers.

Some of the foods that they typically ask people to avoid include:

  • vegetable and fruits with skin and seeds, such as apples
  • raw green vegetables, especially cruciferous ones, such as cauliflower
  • whole grains
  • whole nuts
  • foods high in fat, such as butter
  • alcohol and caffeinated drinks
  • lactose, which is in milk and soft cheeses
  • sugary foods
  • spicy foods
  • nonabsorbable sugars, such as mannitol, which are in certain types of fruits and juices, including pear and peach
  • greasy or fried foods

Many individuals with IBD may need to take supplements to make up for the deficiency resulting from active bowel inflammation, food avoidance, and malabsorption.

Malabsorption makes it difficult to absorb necessary nutrients in the small intestine, such as proteins, fats, sugars, vitamins, and minerals. It can occur as a result of inflammation in the intestines.

A person should speak with a doctor before buying vitamins, supplements, and herbal formulas. If pills cause digestive symptoms, they can consider taking supplements in liquid or powder forms.

It is also crucial to check the label for artificial colors, sugar alcohols, lactose, and preservatives. Some individuals may be sensitive to even small amounts of these substances.

Here are some supplements that people with IBD may need:

A 2019 study reviewed omega-3 fatty acids. It showed that these reduced inflammation, decreased disease activity, and increased the quality of life in people with Crohn’s disease.

However, a 2019 review concluded that there was insufficient evidence to confirm that probiotics were effective in treating IBD and maintaining the balance of gut microbiota.

The same foods do not trigger symptoms in all people with Crohn’s disease. A person may wish to explore which foods are safe for them and which ones trigger symptoms.

Keeping a food journal or diary and tracking their symptoms can help people determine which foods are causing problems.

This information can be useful when a person wishes to discuss their treatment options with a doctor or dietitian.

Learn more about IBD and ways to manage it by visiting our hub.

Based on some research, it is common for people with Crohn’s disease to restrict their fiber intake due to the insoluble nature of many high fiber foods. However, in some individuals, high fiber foods may reduce the risk of flare-ups. They may even reduce the risk of IBD developing in the first place.

It is important to note that all dietary factors can affect individuals with Crohn’s disease differently. Keeping a food journal to track food intake and symptoms can help a person work out what dietary factors exacerbate their condition.