By Dietitian and Nutritionist Alison Bencke
The disadvantages of an overly strict Crohn's diet
If Crohn's disease sufferers follow all the advice found on the Internet or in books about which foods to avoid in their Crohn’s diet, they may risk nutritional deficiencies from such a limited list of allowed foods. Your physician or a dietitian or nutritional expert recommended by your doctor should be consulted before you remove foods from your diet.
Some popular Crohn's diets recommend eliminating particular carbohydrates. However, the scientific evidence for this is far from conclusive. While a few people with Crohn’s report relief from symptoms on these strict regimes, the effect is often short-lived or leaves sufferers on such a restricted diet that they cannot sustain it. Those continuing on these diets may risk nutrient deficiencies from the narrow choices of foods. (Read more about keeping your body in balance in the Summer 2010 issue of Crohn’sAdvocate magazine.)
Everyone is an individual. True food allergy usually means that if you eat even a trace of the offending food, you will have a reaction. Food intolerance means that you can tolerate small amounts of a food, but larger quantities trigger discomfort.
For example, people who avoid milk because they are lactose (milk sugar) intolerant can often cope with small amounts of milk in foods, but they will suffer discomfort if they drink a big milkshake. When Crohn’s is very severe in the small intestine, lactose intolerance may occur. But unless your doctor has diagnosed this, there may be no reason to avoid milk as it contributes a significant amount of protein, calcium, and vitamins in your Crohn’s diet plan. There are also lactose-free milk alternatives available, such as sweet acidophilus milk or soy milk containing calcium.
Back to top
Other foods to avoid in your Crohn’s diet
You should probably avoid foods high in fat and added sugars, as well as the foods you know you can’t tolerate. Do not cut out healthy foods from your Crohn’s diet just because they may bother other patients unless you have had a bad reaction to these foods on more than one occasion. It is important to understand that allergies and food intolerances vary in individuals and you may not be bothered by food that others cannot tolerate. Avoid missing out on your favorite foods unnecessarily.
Back to top
Fiber: high or low?
Advice about foods containing fiber can be confusing, depending on what you read. Choose soluble fiber sources or resistant starch for your Crohn’s diet plan, as they provide short-chain fatty acids.
Historically, starch has been thought to be 100% digested as glucose in the small intestine. But research over the last few decades has found that a significant portion (about 10%) is not digested in the small intestine and passes into the large intestine, where it helps gut bacteria with fermentation. This starch is called resistant starch and many nutritionists think that it should be classified as a component of dietary fiber. The bacteria in the large intestine produce short-chain fatty acids from the resistant starch, which may help maintain the health of cells lining the colon (colonocytes). These fatty acids are also absorbed into the bloodstream and may play a role in lowering blood cholesterol levels.
Having fiber in your Crohn’s diet plan provides food for your good gut bacteria. Soluble fiber is found in oats, rice, or barley bran, but not in wheat bran. Pectins, another source of fiber, are found in fruits and seeds. Plantago ovata (psyllium) is another good source of soluble fiber.
Resistant starch occurs in cooked, cooled foods like potatoes and rice. The cooling process allows gels to form, which resist digestion in the small bowel. Instead, the food enters the large bowel to be digested by bacteria and form volatile fatty acids. These compounds provide fuel for the large bowel cells and may be protective in Crohn’s disease. Thus, increasing the resistant starch in your Crohn’s diet by eating cooked, cooled potatoes, rice, and pasta may be beneficial (see the Pesto Pasta [or Rice] Salad recipe).
If you are having a flare-up, you may need a low-fiber (or low-residue) Crohn’s diet. When you are well and do not have any strictures or blockages, the best advice is to eat a well-balanced diet. Thus you may need to vary your fiber intake depending on the activity of your disease (see the Date Scones recipe, which can be made with whole grain or white flour).
Back to top
Caffeine and Crohn's diets
There is some evidence to suggest that caffeine has a negative effect in Crohn's disease. Caffeine is a stimulant to the central nervous system and should be consumed in moderation. Remember to avoid anything that causes discomfort.
Note: these tips should not replace advice from your physician. Always check with your physician before making any changes to your eating habits.
See also: Videos of people living with Crohn’s, Your body image and Crohn’s, Crohn's treatment options