Eating a Low-Fiber Diet for a Crohn's Disease Flare

Roughage is fiber, which stimulates the bowels—which is great for most people but not those with cramps and diarrhea due to a Crohn's disease flare-up.

Following a diet low in fiber and residue (the indigestible portion of food, including fiber, skins, seeds, and hulls) may ease symptoms of Crohn's disease.

If you're wondering what you can eat on a low-fiber diet, here are several tips to help you get started. Please note that a healthcare provider may recommend seeing a registered dietitian who can tailor a nutrition plan to your specific needs.

What Is a Low Fiber Diet?

Fiber is a type of carbohydrate—found in fruits, vegetables, whole grains, nuts, and seeds—that is not digestible, so it doesn't get broken down or absorbed as it passes through the body. A low-fiber diet is made up of foods that have very little fiber, such as:

• Fruits and vegetables without seeds or skins (bananas, melon, potatoes, beets, string beans)
• Cooked or canned fruits and vegetables
• Refined grains (bread, crackers, and pasta made from white flour; white rice)
• Lean protein (fish, chicken breast, lean ground turkey, eggs, tofu)

Sometimes a low-fiber diet is called a low-residue diet, and fiber is one of the residues. But there isn't a specific definition for either diet, and in practice, the terms are often used interchangeably.

How Long Do You Follow a Low-fiber Diet?

The low-fiber diet is usually recommended to help decrease diarrhea and the number of stools during a flare-up. It's not recommended as a long-term food plan because it can be challenging to get all the nutrients you need on a low-fiber diet, so it should only be used during a flare-up.

Once symptoms have improved and you're feeling better, it's best to gradually return to normal eating patterns with variety and nutrient-rich foods, including fresh fruits and vegetables, whole grains, low-fat dairy, and healthy fats.

With digestive issues, what works best for one person can be different than what works for someone else, so some trial and error is often needed. These tips can guide you toward healthier eating during a flare-up.

Food Preparation Tips

Being mindful of how foods are prepared and incorporating some healthy habits can help reduce the chances of Crohn's disease flare-ups.

Cook Your Veggies

On this diet, most raw fruits and vegetables are off-limits. One way to fit in more fruits and vegetables is by eating cooked or canned versions.

"With many of these [vegetables], when they are cooked, there will still be fiber, but not as much residue," said Jeannie Gazzaniga-Moloo, PhD, RD, a registered dietitian, and professor at California State University in Sacramento, CA.

Vegetables like spinach, butternut squash, pumpkin, parsnips, and carrots should be fine if eaten this way. Potatoes can be eaten without skin (the skins contain most of the fiber), and broccoli and kale are okay, too, if cooked very soft.

Daily Habits

Certain daily habits may help reduce flare-up symptoms and are generally healthy habits to maintain long-term, such as:

• Eat four to six small meals instead of three large meals
• Stay hydrated by drinking water, broth, tomato juice, or electrolyte drinks regularly throughout the day
• If gas in the gut is an issue, drink slowly and consider using a straw to decrease the chance of ingesting air.
• Prepare meals in advance to have foods you tolerate on hand
• Keep a food journal to track the foods you eat and any symptoms you may experience

Foods To Choose

Many people with Crohn's disease have discovered certain foods that are best for them to avoid to help prevent flare-ups. And it's also helpful to know which foods are best to include because they provide valuable nutrition and are less likely to cause symptoms.

Lean Protein

Fatty foods can sometimes worsen symptoms, especially during a Crohn's flare, so low-fat protein choices are healthier and low in fiber. Remove the skin and select lean red meats, like ground sirloin—if you eat beef and can tolerate it.

Other healthy protein sources include:

• Fish
• Chicken breast
• 93% lean ground chicken and turkey
• Eggs
• Tofu

The Crohn's & Colitis Foundation recommends boiling, grilling, steaming, and poaching your food to keep things simple and easier to digest.

Low Fiber Fruits and Vegetables

Fruits and vegetables that don't have skin or seeds and ones that are well-cooked, canned, or pureed are recommended during a flare. Fruit juice without pulp or flavored water might also be fine (sometimes watering down the juice can help).

Some examples include:

• Applesauce
• Bananas
• Cantaloupe
• Honeydew melon
• Canned peaches and pears
• Peeled cucumbers
• Asparagus
• Potatoes without the skin
• Squash
• Canned green beans

Use Caution With Lettuce

Almost all raw vegetables are best to be avoided during a flare-up. However, if you're craving a salad, iceberg lettuce is tolerated by many people if eaten in small quantities.

Try a salad with iceberg lettuce, chicken, peeled and sliced cucumbers, and low-fat dressing without seeds.

Low-fat Dairy or Dairy Substitutes

Due to lactose intolerance, many people with Crohn's don't tolerate dairy even when in remission.

If this is the case, lactose-free milk, soy milk, or almond milk may be your best bet.

Because foods higher in fat can also be more difficult to digest, it's best to stick with low-fat varieties of your favorite ice cream, milk, or yogurt.

Foods To Avoid

Some foods may be best to avoid entirely if they frequently cause symptoms, while others might need to be avoided only during a flare-up.

Whole Grains

Because whole-grain foods are a good source of fiber, it's a good rule to stick to refined, white grains during a flare-up. The best options are foods that don't contain whole wheat flour, like:

• Rice crackers
• Sourdough or gluten-free bread
• Cereals made with rice flour or are gluten-free
• Oatmeal
• White pasta
• White rice

Oatmeal contains fiber, but it's the soluble kind of fiber, meaning it absorbs water and passes through the digestive tract more slowly than the insoluble type you're trying to avoid.

Look for grains with less than one-half gram of fiber per serving, and avoid whole grains of all kinds during a flare.

Raw Fruit, Vegetables, and Nuts

In general, raw fruit should be avoided during a Crohn's flare. Berries, oranges, and fruits with seeds and more fiber—like prunes, raisins, and figs—can be particularly difficult to digest.

Raw vegetables, vegetables with a peel, and cruciferous vegetables—broccoli, cauliflower, cabbage, Brussel sprouts, bok choy, and arugula—should be avoided during a flare because some of them can cause gas and they're harder to digest compared to cooked vegetables.

Whole nuts should be avoided, but creamy peanut butter may be ok—just check with a healthcare provider to be sure.

High Fat Foods

These foods can sometimes be difficult to digest even in remission, so may need to be avoided most of the time, but definitely during a flare-up. High-fat foods include:

• Butter
• Cream
• Coconut and coconut oil
• Mayonnaise
• Fatty meats
• Fried and greasy foods
• Smoked meats like hot dogs, bacon, deli meat, sausage, and bologna
• Ice Cream
• Cakes, pastries, cookies

Other Things To Consider

Along with finding which foods are best for you to include or avoid, there are a few other factors worth knowing about.

Trial and Error

A low-fiber diet is very individualized—you may be able to tolerate some foods and not others, said Gazzaniga-Moloo. And what one person with Crohn's disease tolerates may be very different for another person.

You may also need to avoid alcohol, caffeinated beverages, and spicy foods.

"If someone finds a food that bothers them, they can try to cook it, choose a lower fat option, or with dairy, go for a lactose-free version," Gazzaniga-Moloo said.

Vitamin Supplements

If you eat a wide variety of foods on this diet, you should be able to get most of the vitamins and minerals you need each day. But Gazzaniga-Moloo said it could be difficult to get vitamin B12, calcium, folic acid, and iron, so you may need to take a vitamin-mineral supplement.

This diet will also slow down your bowel movements, so drinking more water and other liquids that you tolerate can help to prevent constipation.

A Quick Review

When it comes to treating a Crohn's disease flare-up, the food plan that works best is often unique to each person, and some trial and error may be necessary. In general, a low-fiber diet can help in the short term with the plan to add more variety and nutrient-rich foods as symptoms resolve.

It may be helpful to talk with a healthcare provider and a registered dietitian, when possible, who can tailor your food plan to meet your individual health and nutrition needs.