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FAQs on Inflammatory Bowel Disease, Diet and Dietary Supplements

By Susan Mikolaitis, RD, LDN, and Ece Mutlu, MD

If you are patient or a family member reading this page, you probably have been told diet does not help Crohn's disease and ulcerative colitis, yet you know or have heard of several people who benefited from dietary therapy. If you are a patient, you may have also noticed that when you change your diet, your disease can get better.

Here are the most common questions we receive about nutrition and diet in patients with Crohn's disease and ulcerative colitis:

What kinds of food may make my IBD worse?

The list of foods that may make IBD patients sick can be extensive. Foods that have been suggested to cause flare-ups include wheat products, dairy, sweets, cruciferous vegetables (broccoli, cauliflower, cabbage, kale, etc.), corn, yeast, tomato products, citrus fruits and juices, eggs, tap water, coffee, bananas, yams, sausages, etc. Yes, you did not read wrong — some studies actually report that tap water can make patients with Crohn's disease and ulcerative colitis sick.

Should I restrict these foods from my diet?

Studies have shown that many patients with IBD restrict their diet to foods that they can tolerate. However, we do not recommend restricting foods. Severe restrictions in your diet are the number one cause of weight loss in patients with Crohn's disease and ulcerative colitis. This can make patients deficient in key nutrients that quiet the immune system and help to heal ulcerated tissue.

If you are obviously restricting your diet and having a hard time finding foods that you can tolerate, a nutritional assessment of your calorie and nutrient intake with regular monitoring by a dietitian may be the one of the most important steps you can take to get better.

Is there a certain type of diet I should follow?

At this time, there is neither any evidence that a specific diet will make your IBD disappear, nor is much really known about the specifics of a diet that one should follow to improve their Crohn's or ulcerative colitis. This is why our IBD researchers at Rush are studying the impact of diet on inflammatory bowel disease.

Several years ago, just like you, we tried to find a scientific answer to that question, especially for our patients who did not seem to get better with existing medications. Our team of IBD experts went through all the existing diet treatments in the medical and non-medical literature, and bought all the books they could on the subject. These books included those that promote the Indian Ayurvedic literature to those formulated in the Western world.

We did discover that many of the diets have some common themes. In fact, most if not all of these diets say that you should be eating more fruits, vegetables, fish, and avoid foods that are heavily processed or full of colorings, additives, and preservatives (i.e. chemicals).

Most diets mention that eating frequent, smaller meals may be better. Beyond these more obvious facts, much of the advice is not scientifically proven even though some of it makes good common sense.

We decided to sift through the time-honored traditional diet therapies in the alternative literature and give them the benefit of testing and proving if they work. We devised diet therapies that make medical and nutritional sense, and are now testing these in a clinical trial.

Based on our interest in this area and our expertise, we have designed the only diet trial in the United States for Crohn's disease. The trial is currently recruiting study participants and is supported by the National Center for Complementary and Alternative Medicine (NCCAM) branch of the National Institutes of Heath (NIH).

How does diet impact my Crohn's disease or ulcerative colitis?

Your diet may affect the types of microbes or bacteria that you have in your intestines, which are a major contributor to the immune reaction in your gut. Your gut has the biggest immune system in your body. IBD researchers have been able to create genetically-modified rats and mice that get colitis much like that seen in IBD. The genetic defect in these animals usually causes an abnormal and overactive immune system which in turn leads the animal's immune system to attack its own colon. This immune attack gives the rats and mice an illness similar to Crohn's and ulcerative colitis. The genetically modified animals experience diarrhea, weight loss, blood in the stool, bloating, fatigue, poor appetite, etc. When the researchers place the genetically-modified animals that get colitis in a germ-free environment (i.e. put them in a bubble- like environment without any bacteria or microbes), these animals do not get colitis; irrespective of how badly damaged the rat's immune system is.

Thus, these experiments tell us that in order to get IBD the immune system must be reacting against the microbes within the intestines. Since, as humans we cannot live in a bubble, one important way to change the microbes in our intestines could be to change one's diet. In fact, at Rush we are studying the types of microbes that reside in the intestines of patients with IBD and how diet may play a role in changing them.

Should I be taking vitamins or minerals?

Patients with Crohn's disease and ulcerative colitis are typically deficient in vitamins B12, A, D, E, K, folate and in the minerals calcium, selenium, zinc and iron. Symptoms of serious vitamin deficiencies are not limited to but include fatigue, numbness in your hands or feet, inability to concentrate on tasks, mood swings, mouth and lip sores, poor healing of wounds, worsening diarrhea, easy bruising, fractures or thinning of the bones, and many more. If you cannot recall the last time your physician checked your vitamin levels or prescribed vitamins for you, you are in need a nutritional assessment by a qualified dietitian who specializes in gastrointestinal disorders.

Why is a nutritional assessment beneficial for an IBD patient?

At Rush, our IBD team believes that medical nutrition therapy is an integral part of treatment and we encourage our patients to have nutritional consultations. Within the limitations of the insurance coverage, we monitor for nutritional deficiencies and supplement these. Nutrition consultation is an extra service that we encourage all our IBD patients to utilize, however, your insurance company may deem it medically unnecessary and decline to pay for medical nutrition therapy with a registered dietitian.

When you schedule a nutrition consultation with us, our gastrointestinal dietitian will assess your current intake, make suggestions of what you can change, and how you can start to change your diet. We will be happy to guide you throughout your dietary endeavors and monitor you for any deficiencies along the way. Learn more about our IBD nutrition assessment services at Rush.

If you live outside the Chicago area, we advise you to schedule a dietary consultation with a respected dietitian specializing in intestinal disorders in your area.

What is enteral nutrition and will it put my Crohn's disease into remission?

Enteral nutrition formulas usually consist of intact, partially digested or near complete digestion of carbohydrates, fats, and proteins with vitamins and minerals added for complete nutrition in a can. They are typically given through tubes that go into the stomach through the skin (G-tube or PEG) or the nose (nasogastric or nasoduodenal tubes). Unfortunately, most of the enteral nutritional formulas are not very tasty, but some people do drink them.

Food is a big part of living and one would not choose to be on enteral nutrition formulas for a lifetime. So even though these treatments are widely used in Asian countries, they are not very popular in the U.S. But, the fact that IBD can get better on this type of nutrition therapy tells us there has to be more research done to find out what other alternatives that incorporate regular foods might work, as when you stop enteral nutrition and start eating a regular diet, your IBD starts coming back.

What kind of chemicals should I avoid in my food? Is there a way to identify them?

Unfortunately, there is not an easy way to identify all the chemicals that may be present in your food. The sources of chemicals could come from the following:

  • Soil or sprays used to grow the food ingredients
  • Chemicals and materials added at the time of processing and packaging
  • Chemicals in the utensils and containers that you use store, carry or eat food

Our most basic and simple advice we can give you is that if you are at the grocery store and wondering whether you should buy a particular food item, then check the label. If you cannot recognize the name of more than one ingredient in a food label, then maybe there is a better alternative to it. The easiest way to control what gets into your body is to grow your own food, eat fresh ingredients and cook from scratch. But like many of us, if you cannot do that or do not have the time, then you may need a dietitian who can direct your food choices.

Will intravenous (IV) nutrition help me before surgery?

If your IBD has caused you to lose more than 10% of your usual weight in a limited time period, caused your Body Mass Index to be less than 18, or prevented you from maintaining an ideal body weight while causing your muscle mass to decline, you may benefit from intravenous (IV) nutrition, also called total parenteral nutrition repletion, for a few weeks prior to surgery.

Having your nutritional status restored (not necessarily with weight increases) can help your intestines heal, your wounds to stay closed and to heal and also can help heal enterocutaneous fistulas with a lot of drainage. In addition, restoring your nutritional status can return you to your activities of daily living sooner after surgery. As with anything, there are risks with supplying your nutritional needs intravenously. Thus, you and your IBD doctor, along with the dietitian, are the best team to decide if the benefits outweigh the risks.

At Rush, we can provide you with a consultation so that you will feel comfortable in making the decision along with your doctor on whether total parenteral nutrition is right for you before your surgery. If we do decide to start you on total parenteral nutrition, Rush has it own home infusion service that will preapprove your nutrition plan with your insurance company. Additionally, the service provides home nurses who will teach you how to self-administer your IV nutrition at home.