Diet and Diverticular Disease: What is the Connection?
To understand the connection between diet and diverticular disease, we first need to understand what it is, and how it can affect you.
What is Diverticular Disease?
Diverticular disease includes both diverticulitis and diverticulosis. Diverticulosis is a condition in which small pouches, called diverticula, form in the lining of the large intestine (colon). Diverticulitis is when the diverticula become inflamed or infected, which can also lead to bleeding diverticula.
Symptoms of Diverticular Disease
Diverticulitis is a common condition, especially in older adults, and often is not accompanied by symptoms, or is ‘asymptomatic.’ Some common symptoms include abdominal pain cramps or irregular bowel habits, however it is thought that these symptoms may be due to a low fiber diet, a common cause of diverticula, rather than diverticulitis itself.
The symptoms of diverticulosis can vary, but common symptoms include:
- Abdominal pain, usually on the lower left side
- Constipation or diarrhea
- Nausea and vomiting
- Fever and chills
- Bloating and gas
- Loss of appetite
- Abdominal tenderness when touched
- Sometimes rectal bleeding (blood in the stool)
It’s important to note that not everyone with diverticular disease will experience all these symptoms, and some people may not have any symptoms at all. If you have severe abdominal pain or a high fever, seek medical attention.
If you have found that you are experiencing one or more of these symptoms, talk to your doctor about your concerns.
What Causes Diverticular Disease?
The exact cause of diverticula and progression to diverticulosis is not well understood, but several risk factors are thought to contribute to its development. These include:
Low-Fibre diet1: Here is where you can see that diet and diverticulitis are closely linked. A diet low in fibre can lead to constipation and increased pressure in the colon, which can cause the formation of diverticula.
Age: Diverticulitis is more common in older adults, likely due to the weakening of the muscles in the colon with age.
Genetics: Some research suggests that a family history of diverticulitis may increase the risk of developing the condition.
Obesity: Being overweight or obese may increase the risk of developing diverticular disease.
Lack of physical activity: People who are sedentary may be at a higher risk of developing diverticular disease.
Medications: Certain medications, such as nonsteroidal anti-inflammatory drugs (NSAIDs) and steroids, may increase the risk of diverticular disease.
In most cases, it is a combination of these factors that can lead to the development of diverticulitis, so it is important to take preventative measures now, by ensuring you are getting enough daily fibre in your diet.
The Connection Between Diet and Diverticulitis
While more research needs to be done to fully understand the cause of diverticulitis, it is thought to be related to a low-fibre diet. Some research has shown that people who eat a diet that is low in fibre are more likely to develop diverticulitis than those who eat a diet that is high in fibre.1
How diet affects the development and progression of diverticulitis:
As mentioned above, a low fibre diet is thought to be one of the risk factors associated with developing diverticular disease. Health Canada recommends Canadian women need 25 grams of fibre per day and men need 38 grams of fibre per day. Most Canadians are only getting about half that much. Working with a doctor or dietitian, it is recommended that you ensure you are regularly consuming the recommended amount of daily dietary fibre, to help prevent diverticulosis and other potential health complications as you age.
The role of fibre in preventing diverticulitis:
Fibre is an important nutrient that helps to prevent constipation and help to regulate the movement of food through the colon. Some studies show that a high fibre diet can help prevent the formation of diverticula by adding bulk to the stool, making it easier to pass, and reducing the pressure in the colon1.
Working with your doctor to find a diet that is right for you when managing diverticular disease:
Depending on whether you are experiencing symptoms or not, your doctor may recommend changes to your diet to help manage diverticular disease. Below are some examples of recommendations your doctor might make, depending on whether you are experiencing a flare (diverticulitis).
Whether in a flare or note, it is always important to work with and follow the recommendations of your healthcare practitioner, such as your doctor or dietitian.
Potential diet recommendations for people with diverticulitis who are not in flare:
Outside of a flare up, people with diverticulosis should work with their doctor or dietitian to build a diet plan that prioritizes fibre. For many of the same reasons mentioned above on how fiber can help prevent diverticulitis, consuming a high fibre diet can also help prevent flare-ups from occurring in the case that a patient has already been diagnosed with this condition.
List of high-fibre foods:
- Fruits: Berries, apples, pears, and oranges are all high in fibre and provide important vitamins and minerals.
- Vegetables: Leafy greens, broccoli, Brussels sprouts, and artichokes are all high in fibre and low in calories.
- Whole grains: Whole wheat, oats, quinoa, and brown rice are all good sources of fibre.
- Legumes: Beans, lentils, and chickpeas are all high in fibre and provide protein.
- Nuts and seeds: Almonds, flaxseed, chia seeds, and sunflower seeds are all high in fibre and provide healthy fats.
- High-Fibre cereals: Look for cereals that are high in fibre like All-Bran, fibre One, and oatmeal
Foods to avoid if you have diverticulosis
If you have diverticular disease but are not actively experiencing a flare, the good news is, you can return for the most part to an unrestricted diet. There aren’t any foods that should be avoided unless your doctor instructs you otherwise.
It’s worth noting that in the past, doctors had recommended that people with diverticular disease avoid certain foods such as nuts, corn, popcorn, and seeds, for fear that they would get stuck in the diverticula and lead to inflammation. However, recent research has shown that there is no scientific evidence to support this recommendation1. In fact, nuts and seeds are components of many high-fibre foods, which are recommended for people with diverticular disease.
Potential diet recommendations for people experiencing a diverticulitis flare:
If you’re experiencing severe symptoms, your doctor may recommend a temporary liquid diet to help alleviate the inflammation. This can include water, fruit juices, broth, and ice pops.
As you begin to feel better, you can gradually re-introduce solid foods into your diet. Your doctor might recommend you follow a low residue diet for a short period of time until your symptoms have completely cleared up.
Some doctors may also recommend a low fodmap diet (a diet commonly prescribed to patients who suffer from Irritable Bowel Syndrome (IBS) for patients experiencing a diverticulitis flare, as some research suggests that high fodmap foods can contribute to pressure in the colon2, which theoretically could possibly inflamed and irritate diverticula if they are present. The type of diet your doctor will recommend will vary from person to person.
If you’re having difficulty structuring a diet on your own, consult your doctor or a dietitian. They can set up a meal plan that works for you.
Probiotics and Diverticulitis:
There has been some preliminary research done that indicate that certain strains of probiotics may be beneficial for patients who suffer from diverticular disease . However, more research needs to be done before a definitive answer on whether or not probiotics may have a positive impact on the condition are needed.
However, it has been shown that a diet that is rich in probiotics can help to promote a healthy balance of gut bacteria, which may help to prevent inflammation and infection. Talk to your doctor and ask if they feel probiotics might be right for you.
Some research has shown that diet plays a role in the prevention and management of diverticulitis1.
For preventing diverticulitis, current research suggests that a high-fibre diet, rich in fruits, vegetables, whole grains, and legumes, can help to promote regular bowel movements, reduce pressure on the colon, and may reduce the risk of diverticula and diverticulitis.
For patients in flare, healthcare professionals may recommend temporarily following a liquid based or low fibre diet like the low residue diet.
Further studies need to be done to fully understand the role that diet plays in preventing and treating diverticular disease. Working closely with your healthcare professional to determine what is best for you is always recommended!
This article was reviewed by Lisa Spiret, MSc, RD
Co-Owner, NutriProCan Dietitians
- Carabotti M, Falangone F, Cuomo R, Annibale B. Role of Dietary Habits in the Prevention of Diverticular Disease Complications: A Systematic Review. Nutrients. 2021 Apr 14;13(4):1288. doi: 10.3390/nu13041288. PMID: 33919755; PMCID: PMC8070710.
- Uno Y, van Velkinburgh JC. Logical hypothesis: Low FODMAP diet to prevent diverticulitis. World J Gastrointest Pharmacol Ther. 2016 Nov 6;7(4):503-512. doi: 10.4292/wjgpt.v7.i4.503. PMID: 27867683; PMCID: PMC5095569.