context: If you have Crohn's disease, you probably have found that certain foods trigger your intestinal symptoms, especially when the disease flares. Learning to avoid these food triggers may allow you to better self-manage your Crohn's disease, reduce gastrointestinal symptoms, and promote intestinal healing. Crohn's disease and ulcerative colitis are two types of inflammatory bowel disease ( IBD). Both involve an immune reaction against the intestinal tract. In ulcerative colitis, the colon is inflamed and the small intestine works normally. With Crohn's disease, often the small intestine is inflamed, making it hard to digest and absorb key nutrients from food. The lack of sufficient nutrients, along with a poor appetite, can lead to malnutrition for people with Crohn's disease. That malnutrition may result from alterations in taste, reduced food or nutrient intake, lack of sufficient nutrients, poor absorption, or the inflammatory bowel disease process itself. When Crohn's disease affects just the small intestine, it results in diarrhea and undernourishment. When the large intestine is also inflamed, the diarrhea can be severe. Severe diarrhea combined with malnutrition often leads to problems. For example, a person with Crohn's disease may suffer from anemia and have low levels of vitamin B12, folic acid, or iron. Nutritional deficiencies and an inability to maintain a normal weight are serious problems for many people, even children, with Crohn's disease. You've probably read about different types of diets for Crohn's disease on the Internet. But the fact is, there is no scientifically proven diet for inflammatory bowel disease. Most experts believe, though, that some patients can identify specific foods that trigger their gastrointestinal symptoms, particularly during disease flares. By avoiding your "trigger foods," you may find that your GI symptoms of gas, bloating, abdominal pain, cramping, and diarrhea are more manageable. At the same time, you will give your inflamed intestines time to heal. If you have had problems absorbing nutrients due to Crohn's disease, it's important to follow a high-calorie, high-protein diet, even when you don't feel like eating. In this setting, an effective Crohn's disease diet plan, based on recommendations from experts, would emphasize eating regular meals -- plus an additional two or three snacks -- each day. That will help ensure you get ample protein, calories, and nutrients. In addition, you will need to take any doctor-recommended vitamin and mineral supplements. By doing so, you will be able to replenish the necessary nutrients in your body. The foods that trigger symptoms differ for each person with Crohn's disease. To know which foods to leave out of your diet plan, you'll need to determine which foods, if any, trigger yours. Many people with Crohn's disease find that one or more of the foods on the following list aggravate symptoms during disease flares. It's possible that at least some of these listed foods will trigger your symptoms: alcohol (mixed drinks, beer, wine) butter, mayonnaise, margarine, oils carbonated beverages coffee, tea, chocolate corn dairy products (if lactose intolerant) fatty foods (fried foods) foods high in fiber gas-producing foods (lentils, beans, legumes, cabbage, broccoli, onions) nuts and seeds (peanut butter, other nut butters) raw fruits raw vegetables red meat and pork spicy foods whole grains and bran Once you've identified foods that cause your symptoms to flare, you can choose either to avoid them or to learn new ways of preparing them that will make them tolerable. To do that, you'll need to experiment with various foods and methods of preparation to see what works best for you. For instance, if certain raw vegetables trigger a flare, you don't necessarily need to give them up. You may find that steaming them, boiling them, or stewing will allow you to eat them without increased GI symptoms. If red meat increases fat in the stools, you could try eating ground sirloin or ground round to see if you can tolerate a leaner cut of beef. Or you might decide to rely on low-fat poultry without skin and fish as your main sources of protein. A low-residue diet is one that's low in specific foods that add residue to the stool. Many individuals with small-bowel Crohn's disease have a narrowing or stricture of the lower small intestine (the ileum). For them, a low-fiber with low-residue diet can help lessen abdominal pain, cramping, and diarrhea. And while scientific proof is lacking, this diet may also help decrease frequency of bowel movements for some people. Foods to avoid on a low-residue diet may include: corn hulls nuts raw fruits seeds vegetables Yes. Keeping track of the foods you eat each day can help you identify the "offenders" -- foods that may trigger symptoms. Avoiding these foods, especially when your disease is active, may give you better control of the symptoms. You can also use a daily food diary to help you and your doctor determine if you're getting a properly balanced diet. It can show whether you are getting enough protein, carbohydrates, fats, and water. It can also show whether you are getting enough calories to maintain your weight and energy. To start your diary, record the foods you eat each day and the serving sizes in a small notebook. Enter the date, food, and any symptoms you might feel after eating this food in the notebook. After a month or two, set up a time to review your food diary with a registered dietitian. The dietitian can determine if you're getting essential nutrients in a well-balanced meal plan or if you might need supplements. Proper nutrition helps the body heal itself and keeps you well. So, having a nutrition discussion with a registered dietitian is important to your overall health and to the management of Crohn's disease. Limiting some food triggers may help control your symptoms during disease flares. But don't restrict yourself so much that you make malnutrition, which often accompanies Crohn's disease, worse. You'll need to find other sources to replace calories, protein, carbohydrates, and fats that are in the foods you eliminate. To do that, you'll need to focus on including nutrient-dense foods in your diet plan. While fast foods should normally be avoided in a healthy diet plan, sometimes they can give your diet a needed boost when used sparingly. Some fast foods can offer a valuable supply of key nutrients and calories. For instance, pizza offers calories, protein, and nutrients such as calcium and vitamins A, B, C, and D. A milkshake is high in calories and calcium. Of course, if you are lactose-intolerant, you need to remember to take the proper medication before drinking a milk product. Ask your doctor or dietitian about vitamin and mineral supplementation. For example, many people with Crohn's disease have a vitamin D deficiency. A study published in the American Journal of Preventive Medicine reported that higher doses of vitamin D (1,000 to 2,000 IU each day) may be beneficial, particularly in reducing the risk of colorectal cancer, which may be higher in individuals with IBD. The National Academy of Sciences has established that a dose of 2,000 IU/day of vitamin D is safe. But it's still important that you check with your personal physician to see what dosage is ideal for your situation. Some research suggests that liquid diets might help people with certain health conditions, and there is evidence that some people with Crohn's disease may benefit from a high-calorie liquid diet, particularly during a flare. By giving the intestines a much needed rest, the liquid diet can help suppress symptoms of Crohn's disease. In addition, the liquid diet or special high-calorie liquid formulas can help people with Crohn's who need extra nutrition short-term or those whose intestines cannot absorb proper nutrition from whole foods. Some people with Crohn's disease enjoy supplements such as Ensure Plus or Boost Plus when they need a boost in calories and nutrients. Numerous studies using fish oil and flaxseed oil suggest an important role for good fats in the inflammatory response that characterizes IBD. The studies, though, are inconsistent on whether or not omega-3 fatty acids have a specific anti-inflammatory effect with IBD. If you want to add omega-3 fatty acid supplements to your diet, talk with your doctor first. Other studies are just beginning to examine the possibility that probiotics or "good" bacteria may be beneficial in Crohn's disease and ulcerative colitis. More studies are needed, though, to determine if these supplements can aid in healing the intestine in IBD.