For most people, the concept of going on a diet is reserved for losing weight or trying to become more healthy. Yet some diets have a totally different purpose that can be related to a certain health affliction or the need to prepare for a particular surgery or medical procedure. Examples of this include gluten-free and low-FODMAP diets, but one that often gets overlooked is known as a low residue diet. 

What is a Low Residue Diet?  

A low residue diet is also sometimes also referred to as a low fiber diet, though the two terms aren’t necessarily interchangeable. The primary purpose of the diet is to reduce the number of bowel movements a person has during a given day or week. In addition to having fewer bowel movements, a low residue diet typically also seeks to reduce the size of stools that are passed. Traditionally this type of diet is meant for a short duration, often in preparation for an upcoming medical procedure. 

In terms of digestion, “residue” refers to the various bits of undigested food and waste material that enter the colon after food has been through the small intestine. Since dietary fiber is the plant-based part of food that doesn’t get digested by the gastrointestinal system, it does make up a large portion of typical stools. Yet there are other foods, such as dairy products, that can also leave residue that will eventually be part of the stool.   

Conditions That May Require a Low Residue Diet 

As noted above, neither a low residue diet nor a low fiber diet are meant to be long-term solutions; in fact, too many Americans have too little fiber in their diet in general, and this is associated with a number of negative health outcomes (including overweight and obesity). Instead, this kind of diet is a temporary change to your eating habits that is intended to substantially reduce the volume of feces that is moving through the digestive tract. 

There are numerous reasons why it might be beneficial to reduce the quantity and size of your bowel movements, but for most people the purpose is either to prepare for a procedure or to make it easier on the gastrointestinal tract when certain conditions are present. Below are some of the more common reasons why your doctor might recommend a low residue diet: 

Preparation 

  • Abdominal Surgery: For almost any kind of abdominal or gastrointestinal surgery, fasting or a low residue diet is recommended in order to keep the digestive tract as free from material as possible. 
  • Colonoscopy: Since the primary purpose of a colonoscopy is to clearly view the inside of the colon, a low residue diet ensures that the colon is clear of significant amounts of waste material that might make it more difficult for the doctor to fully examine the colon. 
  • Hemorrhoid Treatment: Most hemorrhoid treatments involve easing symptoms until the condition resolves itself, so it then becomes important for stools to be smaller and softer through either a low fiber diet or stool softening medication.
  • Cancer Treatment: Some types of cancer treatment can be particularly harsh on the digestive system, so a low residue diet can help reduce irritation and lower the risk of bowel obstructions.  

Recovery

  • Inflammatory Bowel Disease (IBD): This group of conditions is characterized by inflammation in the large intestine and small intestine. A low residue diet is sometimes necessary during acute stages of the disease; relevant subsets of IBD include Crohn’s disease and ulcerative colitis. 
  • Diverticulitis: Similar to IBD, diverticulitis involves inflammation of the small colonic pouches called diverticula. A low residue diet can be used to rest the bowels after considerable inflammation. 
  • Gastroparesis: Also known as delayed gastric emptying, this condition causes weak peristaltic contractions in the stomach that lead to slower bowel motility and thus a greater chance of constipation.  

What is Involved in a Low Residue Diet?   

The main purpose of this diet is to reduce the amount of material traveling through the digestive tract; as noted, passing smaller and less frequent stools can be very helpful, especially when there is inflammation present in the colon. It can also ease the discomfort associated with diarrhea, bloating, gas, and cramping. Generally speaking, participation in the diet means limiting or eliminating any foods that are high in fiber or are likely to cause excess residue in the colon. Below is a list of foods to avoid and foods that are appropriate for the diet: 

Foods to Avoid

  • whole grains, oatmeal, granola, shredded wheat
  • seeds, nuts, chunky peanut butter 
  • beans, lentils, peas 
  • brown rice, wild rice, quinoa  
  • popcorn 
  • dried fruit, coconut, apricots 
  • cheese, milk, milk products (especially if you’re lactose intolerant) 
  • skins and seeds of most fruits and vegetables

Acceptable Foods

  • meat, poultry
  • fish, shellfish 
  • ham, bacon, cold cuts  
  • eggs
  • tofu 
  • white rice 
  • white bread
  • pasta, plain tomato sauce (seedless) 
  • some canned veggies such as carrots or green beans 
  • well-cooked potatoes, beets
  • cereals with less than 2 grams of dietary fiber (corn flakes)
  • fruit juices and vegetable juices 
  • baked goods made with refined rye or wheat flour 
  • applesauce 
  • certain fruits, including ripe bananas, cantaloupe, honeydew, and canned peaches 
  • oils, butter, margarine 
  • creamy peanut butter
  • salad dressing
  • condiments like ketchup and mayonnaise 
  • hard candy, ice cream, sherbet

To really maximize the effectiveness of the diet, it’s important to make sure that all foods are prepared so that they are tender, soft, and easy for the digestive system to break down; poaching, simmering, stewing, and braising are examples of preferred cooking methods. The nature of the diet can also potentially lead to constipation, so it’s similarly important to drink plenty of water and other fluids so that the digestive tract remains sufficiently hydrated. 

Make a Gastroenterologist Appointment

A low residue diet should only be used in consultation with a doctor or dietitian when the need arises; in general, it is better to have a high fiber diet in your regular life. But when a sensitive bowel condition crops up, a low residue diet can be instrumental in helping to resolve it. Depending on the procedure or medical condition, you might need to stay on the diet from a few days to a few weeks before fiber and other foods can be reincorporated.  At Cary Gastro, we are always passionate about providing excellent digestive healthcare for all of our patients. If you have been having abnormal bowel movements or other gastrointestinal symptoms, it may be time to talk with a gastroenterologist. For more information on the conditions we treat, or to speak with a doctor, please contact us today to request an appointment.