A low residue diet limits high fiber foods. It may help reduce the frequency and size of bowel movements. This type of diet may be helpful for people with certain conditions, such as Crohn’s disease.

A low residue diet also limits dairy products that can result in high colonic residue.

A medical professional may prescribe a low residue diet to people who experience various forms of gastrointestinal issues or to prepare for diagnostics for said issues.

This article explains the components of a low residue diet. It also goes over how it works, its uses, and the risks and benefits of this type of diet.

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A low residue diet excludes or limits foods that contribute to stool weight, such as high fiber foods, including whole grains, fruits with the peel, and vegetables.

Doctors who recommend this diet intend it to be both diagnostic and therapeutic for people who:

  • are preparing for a colonoscopy
  • have inflammatory bowel disease (IBD), such as Crohn’s
  • are preparing for or recovering from bowel surgery
  • have infectious colitis
  • have acute diverticulitis

The intentionTrusted Source of a low residue diet is to help clear or heal the colon by allowing time for bowel rest.

Healthcare professionals often use the terms “low residue diet” and “low fiber diet” interchangeably.

However, a low residue diet also involves limiting dairy products. Dairy contains little fiber but contributes considerably to gut residue and fecal bulking.

A low residue diet limits dietary fiber to 10–15 grams per day.

The goal is to reduce bowel activity and promote intestinal healing by minimizing the intake of indigestible material.

These indigestible materials include:

Fiber

Fiber, also known as roughage or crude fiber, is a carbohydrate the body cannot break down into sugar molecules. It helps the body regulate sugar and hunger. There are two types of fiber:

  • Soluble fiber dissolves in water. It is found in foods such as oatmeal, nuts, lentils, chia seeds, apples, and blueberries. Soluble fiber can help lower glucose levels and lower blood cholesterol.
  • Insoluble fiber is found in whole grains, legumes, leafy greens, nuts, seeds, and fruit. Insoluble fiber is indigestible, so it helps food move through the digestive system, encouraging bowel regularity and preventing constipation.

Residue

“Residue” refers to food that is low in crude fiber but contributes to waste. Foods that contribute to residue that are low in fiber include:

  • meats
  • fats
  • dairy products

A low residue diet aims to produce fewer and smaller bowel movements to help clear the intestinal tract.

However, low residue diets were removed from the American Academy of Nutrition and Dietetics Nutrition Care manual in 2012.

Healthcare professionals no longer recommend a low residue diet for Crohn’s disease, ulcerative colitis, bowel resection, and ileostomy.

However, some medical professionals may still recommend low fiber therapy in the following cases:

IBD: Crohn’s and ulcerative colitis

Doctors may prescribe a temporary low fiber or low residue diet to people experiencing an active IBD flare to ease symptoms such as:

  • rectal pain
  • diarrhea
  • cramping
  • bloating
  • gas
  • bleeding

Colonoscopy preparation

Endoscopists typically recommend a temporary low fiber diet to people 24 hours before a colonoscopy.

Some endoscopists might recommend a 3-day low fiber diet, but there is no evidenceTrusted Source to support it improves colonoscopy results.

Bowel surgery

People preparing for colon surgery, such as an ileostomy, colostomy, or bowel resection, may need to follow a low residue or liquid-only diet before the procedure.

They may also have to follow this diet after surgery to help speed healing.

While there is little high quality evidence to support the effectiveness of a low residue diet for colon surgery preparation and healing, some healthcare professionalsTrusted Source may still recommend it based on their clinical experience.

One 2014 studyTrusted Source included 111 people undergoing colorectal surgery. Participants who followed a low residue diet instead of a liquid diet after colon surgery had a quicker return to typical bowel function and shorter hospital stays.

Diverticulitis and IBS

Healthcare professionals may recommend a temporary low residue or low fiber diet to people with diverticulitis experiencing flare-ups.

However, people with diverticulitis should eat a high fiber, low fat diet when they are not experiencing a period of inflammation.

Additionally, healthcare professionals may suggestTrusted Source a low residue diet to people with irritable bowel syndrome (IBS) to help ease discomfort. However, it is more common for doctors to recommend a low FODMAP diet.

The potential benefits of a low residue diet include:

  • allows for “bowel rest” and may speed healing
  • might help decrease painful symptoms of IBD, such as:
    • bloating
    • gas
    • rectal or intestinal bleeding
    • diarrhea
    • cramps

Possible risks of a low residue diet include:

  • Constipation: Insoluble fiber moves waste through the intestine. A lack of it can result in constipation.
  • Nutrient deficiency: Eating a diet low in fruits, vegetables, and whole grains may make it difficult to receive sufficient nutrition. There is extensive evidenceTrusted Source showing that a diet high in fiber-rich and plant-based foods is beneficial for health.
  • Limited supporting evidence: As mentioned earlier, there is also little high quality evidence to support the effectiveness of a low residue diet.
  • Evidence against effectiveness: An older 2-year controlled studyTrusted Source in Italy found that the long-term implementation of a low residue diet made no difference when evaluating flare-up rates, intestinal obstructions, a need for surgery, and hospital admission.

People should only follow a low residue diet if a qualified medical professional prescribes it.

Recommendations from healthcare professionals on what to eat when following a low residue diet may vary. Acceptable foods may include:

  • refined breakfast cereals
  • products made from white flour, such as white bread and pasta
  • well-cooked white rice and rice noodles
  • eggs
  • plain tofu, textured vegetable protein, and seitan
  • boneless fish
  • lean meat
  • seafood
  • vegetable juices or clear soups free of seeds or skins
  • fruit juice
  • avocado
  • skinless stewed or canned fruit
  • sieved pureed fruit
  • plain cakes
  • custard

High residue foods include:

  • whole grain cereals
  • nuts and seeds
  • all milk, milk alternatives, and dairy products
  • brown rice, quinoa, and whole wheat pasta
  • small, boned fish, such as whitebait
  • vegetable stalks, skins, seeds, and peels
  • fruits with seeds or pips
  • smoothies with seeds or skins
  • corn
  • legumes and pulses
  • potato skins
  • peanut butter

Evidence suggests that dairy contributes to higher amounts of residue than other foods, potentially due to lactose malabsorption.

A sample menu for someone following a low residue diet might include the following:

Breakfast

  • 2 slices of toasted white bread with smashed avocado
  • 2 poached eggs
  • 1 small glass of fruit juice

Lunch

  • couscous with tofu or lean chicken breast
  • simple salad dressing
  • 1 small glass of clear vegetable broth or vegetable juice

Dinner

  • skinless and boneless salmon fillets baked in lemon juice and olive oil
  • mashed or pureed potatoes with the skins removed
    • Note: Mash the potatoes with olive oil to avoid adding dairy.
  • 1 small glass of vegetable juice

Dessert

  • 1 chocolate chip cookie

There is minimal evidence to support the effectiveness of a low residue diet.

People should only follow a low residue diet under the supervision of a healthcare professional to ensure they get adequate nutrition.