The cause of IBD is complex and is not caused by just one thing. IBD seems to be caused by a mix of genes and things that damage the lining of the intestine. Together, these cause the immune system in the intestine to be exposed to the bacteria of the intestine more than usual. Inflammation in the intestine of a healthy person lasts for a short time, and then goes away. In people with IBD, the inflammation does not go away, and it stays inflamed.
For a long time, it was thought that diet did not matter when it comes to managing IBD. Growing research suggests that food does matter, and diet is recognized as a risk factor for the development of IBD. Increasing evidence associates a Western diet and ultra-processed foods with the development of IBD, while higher intakes of fiber containing foods may be protective.
No. Although some people with IBD have allergies to certain foods, neither Crohn's disease nor ulcerative colitis is caused by food allergy.
Although certain foods can make GI symptoms worse, there is no proof that inflammation of the intestine or an IBD flare is directly caused by eating a specific food or meal. However, overall dietary patterns overtime may improve or worsen inflammation and there is ongoing research in this area.
No. There is no proof that any diet will truly stop or prevent the inflammation of IBD.
Yes, an all-liquid diet of nutrients, called exclusive enteral nutrition (EEN), has been shown to reduce inflammation in the intestines in people with Crohn's Disease. EEN involves using a formula as the only source of nutrition (no solid foods) for a period of 4-12 weeks. This could be given via a feeding tube or consumed by mouth. This is a more popular approach in children, but EEN may also be considered in adults who are intolerant to steroid therapy or used as a bridge to safer elective surgery. At this time the use of any other specific dietary therapy as a treatment for IBD is considered experimental and recommended to use with and not in place of medical therapy.
There are other diets that may be used to help lessen GI symptoms. One of the best proven diet is the Low FODMAP diet which is a 3-phase approach and it's recommended to work with a FODMAP specialized dietitian. Additionally, the Mediterranean Diet and Specific Carbohydrate Diet diet were recently shown to bonessth improve GI symptoms in people with Crohn's Disease.
Lactose intolerance is a condition in which the body does not properly digest lactose, which is a sugar found in dairy and certain dairy products. For example, dairy milk has lactose where as hard and aged cheese is naturally lactose-free. Lactose intolerance may lead to cramping, abdominal pain, gas, diarrhea, and bloating. The best way to diagnosis lactose intolerance is by cutting it out short term and see if you feel better. You can then eat or drink some lactose containing dairy foods and see how you tolerate them. Lactose intolerance is common in the general population so some people with IBD may also be lactose intolerant. Others may only have problems with lactose digestion during a flare or after surgical removal of a segment of the small intestine.
Many people with IBD are not able to tolerate certain foods. A food and symptom diary can help you figure out which foods bother you and just as important, which foods you tolerate well.
During an IBD flare many people find that certain foods or eating patterns increase their symptoms such as eating larger meals, high fat/greasy foods, caffeine, alcohol, dairy, high sugar foods/drinks, and foods high in fiber, particularly insoluble fiber.
It is very common for patients with IBD to restrict fiber containing foods: fruits, vegetables, beans, whole grains, nuts, and seeds. This can lead to over-restriction in the diet, cause significant overwhelmness, and impact quality of life. There are times where a low fiber diet may be beneficial in IBD, for example someone with a stricture or potentially during a flare (but this is very individualized). However, the long-term goal is for people with IBD to consume a moderate-to-high fiber diet and eat approximately 20-35 grams of fiber per day, which is the same fiber recommendation for the general population.
It is a good idea for most people with IBD to take a standard multivitamin every day. People with IBD who are doing well and eating a nutrient-dense, balanced diet likely do not need any extra vitamins or minerals. If you have Crohn's disease in the ileum (the last part of the small intestine) or the ileum has been removed you may need to take B12, calcium, or vitamin D. You may need iron supplements if you have blood loss during inflammation or reduced iron absorption as a result of inflammation. Diarrhea or vomiting can cause loss of potassium and magnesium. If you are lactose intolerant and avoid dairy products, this can lead to low calcium intake. Ask your doctor if you need to be tested for any of the above.
During a period of active inflammation, any food can make pain, bloating, cramping, and diarrhea worse. However, you still need to eat during a flare. You also need to drink plenty of fluids with salt and water so that you absorb and retain fluid. Many people switch to a bland diet or to an all-liquid diet during a flare. Bland foods like rice, toast, bananas, applesauce, broth-based soups, and nutritional drinks like Orgain, OWYN, Carnation Breakfast Essentials, ENU, Boost or Ensure can help.
A low-residue diet limits the amount of fiber and other material that cannot be digested as it passes through your small intestine. A low-residue diet reduces the size and number of your stools and helps relieve abdominal pain and diarrhea.
White (refined) breads, cereals and pasta (with less than 1 gram of fiber/serving), white rice, poultry, fish, eggs, oil, margarine, butter, mayonnaise, smooth salad dressings, broth-based soups (strained), jelly, honey, syrup.
Whole-grain breads, cereals, and pasta, whole vegetables and vegetable sauces, whole fruits, including canned fruits, yogurt, pudding, ice cream, or cream-based soups with nuts or pieces of fruits or vegetables, tough or coarse meats with gristle and luncheon meats or cheese with seeds, peanut butter, salad dressings with seeds or pieces of fruits or vegetables, seeds or nuts, coconut, jam, marmalade.
If you are struggling with what and how to eat, please connect with a specialized GI dietitian. If you are a patient at Michigan Medicine, ask your GI doctor for a referral. Learn more about Michigan Medicine's GI Nutrition Services.