A low-fiber diet contains foods low in fiber that a person can easily digest and absorb, such as white bread or rice, pressed fruit juice, and vegetables with no skins or seeds.

Fiber is a substance in plant-based foods that remains undigested as it passes through the small intestine. For most people, fiber is useful for helping stools forms and pass through the digestive system. It also supports the health of the microbiome.

But for those with digestive conditions such as inflammatory bowel disease (IBD), too much fiber can sometimes make symptoms worse during a flare-up. People preparing for a colonoscopy may also need to follow a low-fiber diet, depending on their doctor’s recommendations.

In this article, we look at what foods to include and those to avoid when following a low-fiber diet.

Most adults need fiber to keep their digestive system healthy. However, a high-fiber diet may exacerbate the symptoms of some medical conditions.

A person may find it helpful to eat a low-fiber diet if they:

That said, there is currently no strong evidence that low-fiber or low-residue diets help to shorten the duration of an IBD flare-up. Evidence-based dietary advice for IBD is generally limited, as it has been difficult for scientists to study.

The charity Crohn’s and Colitis UK recommend eating a balanced diet with fiber when well, and adjusting it when having a flare-up. This may involve:

  • eating soft, easy-to-digest foods in as much variety as possible
  • using calorie-dense foods to avoid weight loss
  • drinking enough water
  • asking a doctor about taking multivitamins if getting a balanced diet is not possible

Foods to avoid on a low-fiber diet may include:

The following foods may be part of a low-fiber diet, depending on individual symptoms and tolerance:

  • baked goods made with white flour, such as white bread, pita, naan, flour tortilla, noodles, pasta, crumpets, and crackers
  • products made with white rice, such as rice puffs, rice cakes, rice noodles, or rice crackers
  • cooked potatoes with skins removed
  • small amounts of fruits with pits and skin removed, such as ripe banana, melons, and tinned fruit
  • smooth fruit juice
  • smooth peanut butter
  • vegetables without peel, seeds, or stalks
  • sieved soups or broths
  • smooth tomato sauce
  • meat, fish, eggs, and tofu
  • dairy products, if they do not cause additional symptoms

Even if a person is only following a low-fiber diet for a for a short time, it is still important to try to eat a variety of foods. This can help a person get the nutrients and calories they need.

Below are some ideas for things people on a low-fiber diet could eat at each meal of the day:

Breakfast

  • low-fiber cereal, such as rice puffs, with milk
  • white sourdough toast with jelly or smooth nut butter
  • crumpets
  • poached eggs

Mid-morning snack

  • smooth yogurt or kefir
  • applesauce with cinnamon
  • one small ripe banana

Lunch

  • turkey sandwich on white bread
  • chicken noodle soup with a small bread roll
  • white pasta with tuna and mayonnaise

Mid-afternoon snack

Dinner

  • tofu stir fry with rice or noodles
  • baked salmon with pasta and low-fiber vegetables
  • chicken with mashed potato
  • omelet

Below are some tips for starting a low-fiber diet:

  • Start slowly: When introducing new foods, add only one at a time, starting with a small quantity and working upwards. This will help a person identify foods that make their symptoms worse, and what portion size is okay for them. It may help to keep a food diary during this time to record the results.
  • Cook from scratch: Where possible, it can help to prepare food from scratch so that a person knows exactly what ingredients it contains. When purchasing preprepared or packaged foods, check the ingredients label for anything that may trigger symptoms.
  • Avoid bits: In general, it may help to avoid foods with pieces in them, such as fruit yogurts, marmalades, and crunchy peanut butter.
  • Preparation is key: In addition to food choices, food preparation can also help make things lower in fiber. For example, peeling fruits and vegetables and sieving lumpy soups may make them easier to tolerate.
  • Little and often: For those having an IBD flare-up, it may help to eat more frequent, smaller meals to get enough calories.

Fiber is one component of food that may aggravate symptoms in some people with IBD, but it may not be the only component that has this effect. Other things that may worsen an IBD flare-up include caffeine and alcohol.

It may help to work with a dietitian to identify a person’s individual triggers, while also ensuring a person eats as varied and nutritious a diet as possible. A dietitian can put together a tailored meal plan to suit the person’s individual needs.

If a person is unsure about what types of foods they should be eating before a colonoscopy or surgery, they should contact their doctor. The doctor should be able to provide information about what to eat and avoid.

If a person has eaten something high in fiber by mistake, they should also tell the doctor about this.

For those with IBD, if eating or digestion continues to be painful without improvement, it is important to speak with a doctor. Seek immediate help if a person:

  • vomits blood
  • has severe abdominal pain
  • has a high temperature and rapid heartbeat
  • is bleeding from the anus and it does not stop
  • has signs of dehydration, such as a dry mouth, lack of sweat or tears, confusion, or loss of consciousness
  • has signs of severe malnourishment
  • has a blocked stoma

Some types of bowel obstruction are serious and potentially life-threatening. If a person suspects a bowel obstruction but has not yet had a diagnosis, they should also seek immediate medical attention. The potential symptoms of a bowel obstruction include:

  • inability to pass any stool
  • severe abdominal pain
  • vomiting

Low-fiber diets contain a variety of foods that are low in soluble or insoluble fiber. Foods to avoid include whole grains, whole wheat breads and pasta, beans and pulses, and vegetables or fruit with seeds and skins.

Foods that may be okay to eat include low-fiber, peeled fruits and vegetables, white breads and pasta, rice, meat, fish, and eggs.

With careful planning, it is still possible to get all the essential nutrients from low-fiber foods, but people who need to follow this diet for any length of time should get support from a dietitian if they can.