What is Diverticulitis? Strategic Guide for Foods to Eat and Foods to Avoid!

Medically reviewed by June 27, 2024| Written by

What is Diverticulitis? Strategic Guide for Foods to Eat and Foods to Avoid!

To understand diverticulitis, we first need to learn some new vocabulary – at least I had to! 

  • Diverticulum: a small pocket that protrudes outward from the wall of the large intestine.  
  • Diverticula: multiple protruding pockets. 

Diverticulosisis a medical condition in which a person develops protruding pockets on their colon wall. But it’s calleddiverticulitis when these same pockets become inflamed for any reason. 

Normally, the wall of the colon is smooth with no protrusions. But these often develop in people aged 50 or above. A diverticulum develops when the colon wall becomes weak and gives way. Diverticula usually appears in the lower part of the colon. 

Most people are unaware that they have the condition until they develop pain and visit a doctor to find out what the reason for the pain is. Only about10% to 25% of patients with diverticulosis develop diverticulitis. 

There are four types of diverticulitis:Acute, Chronic, Uncomplicated, and Complicated.

  • Acute diverticulitis develops suddenly but also goes away quickly if treated. 
  • Some people will have repeat episodes, while others develop chronic inflammation. 
  • People mostly develop uncomplicated diverticulitis which only manifests as inflammation or infection and so, can be easily treated. 
  • Complicated diverticulitis, the inflammation causes secondary problems such as abscesses, tearing of the diverticula, or intestinal obstruction.

Can you guess what you can do to prevent diverticulitis? Don't worry if you can't. You'll find out as you read the article.

What Does a Diverticulitis Attack Feel Like? 

A diverticulitis attack is characterized by sharp, severe abdominal pain. It usually comes on suddenly but may also start as mild pain worsening over several days. The pain is usually felt in the lower left side of the abdomen but people of Asian descent may feel pain on the right side of the abdomen. 

The abdominal pain can be accompanied by:

In severe cases, complications can arise, including: 

  1. Intensified abdominal pain becomes more widespread.
  2. A high fever may indicate a more serious infection.
  3. Abscesses in the abdomen - which are very painful and can increase fever.
  4. If the diverticulum ruptures, then it may cause peritonitis - a serious and extremely painful infection of the abdominal cavity lining.
  5. Intestinal obstruction because of inflammation, resulting in severe pain, bloating, and vomiting,
  6. Blockage or inflammation can increase the pressure in the intestines, resulting in intestinal ulcers. When an ulcer pushes through the thickness of the intestinal wall, it can create an opening that connects to another organ i.e. Fistula formation.

What is the Main Cause of Diverticulitis?

The cause behind diverticulitis is still not completely understood. Ongoing research has highlighted several contributing factors: 

1. Diverticulosis

Diverticulosis or the presence of diverticula (protruding pockets of the large intestine) increases the risk of diverticulitis. 

2. Chronic Inflammation

Several studies have associated diverticulitis with a chronic inflammatory state. The risk factors for diseases like cardiovascular disease and diabetes are the same as those for diverticulitis, such as obesity, physical inactivity, and a Western diet.

3. Altered Microbiomes

Changes in the gut microbiota are implicated in the origin and development of many intestinal disorders. Several studies have examined the intestinal microbiomes of patients with diverticulitis and found the composition of the intestinal microbiome in patients with diverticular disease is different from those without the disease.

4. Fecal Impaction or Blockage

Diverticulitis occurs when a diverticulum becomes blocked by fecal matter, undigested food particles, or other material, creating a favorable environment for bacterial growth - leading to infection and inflammation.

5. Genetics

Two large Scandinavian twin or family studies have shown that genetic factors increase the risk for diverticular disease. Statistical modeling estimated that genetic factors accountedfor 40-50% of the risk for diverticular disease.

6. Low-Fiber Diet

Most evidence suggests that the functional alterations in cells or tissues characteristic of the disease are the response to a lifelong consumption ofa low-residue diet. However, scientists stress that other factors like genetics may influence the impact of a low-fiber diet. 

7. Medications

Several medications have been associated with an increased risk of diverticulitis. Studies have found a consistent positive association betweennonsteroidal anti-inflammatory drug (NSAIDs) use and diverticulitis.

Can Diverticulitis be Cured? 

Effective treatments for the condition may involve antibiotics, diet recommendations, lifestyle changes, and surgery in severe cases. 

1. Antibiotics and Painkillers

In uncomplicated diverticulitis, the diverticula and the surrounding intestinal lining are inflamed but there are no abscesses with pus. About 80% of all diverticulitis cases are uncomplicated. They usually don’t require antibiotics as95% of these cases resolve on their own within a week. 

Doctors may prescribe painkillers butnot NSAIDs like ibuprofen or diclofenac because they can increase the likelihood of complications such as intestinal perforations.

Earlier, physicians used to treat acute diverticulitis with antibiotics, and surgery was advised for recurrent cases. However, ongoing research has led to a less aggressive medical approach to this disease. For instance, doctors are advised to useantibiotics only if they must. 

About 80% of all cases of complicated diverticulitis clear up within a few weeks of treatment with antibiotics. However, 20 out of every 100 patients require surgery and antibiotics are used to keep the infection from spreading.

2. Dietary Recommendations 

Some doctors prescribe a liquid diet of soups, broth, clear juices, and jelly during the acute phase of diverticulitis. The idea is to provide enough hydration and electrolytes while allowing the bowel to rest simultaneously.

After a few days on the liquid diet, low-fiber foods like white bread, white rice, and so on are introduced. But it's crucial to reintroduce fiber-rich foods into the diet.

A high-fiber diet which includes whole grains, fruits, vegetables, and legumes; prevents constipation and promotes regular bowel movements. Ultimately, this reduces pressure on the intestine which may otherwise contribute to diverticular issues.

3. Lifestyle Recommendations

Diet and lifestyle modification can prevent diverticulitis. Lifestyle risks for the development of diverticulitis include eating excessive red meat, a low-fiber diet, lack of exercise, smoking, and being overweight. A study that involved these factors found that following a low-risk lifestyle decreased the risk of diverticulitisby nearly 75%. 

What Foods Trigger Diverticulitis? 

Some people with diverticulitis find their symptoms seem to worsen when they eat certain foods. Avoiding these foods can be an excellent way to limit diverticulitis flare-ups. Since individuals react differently to foods, it's impossible to come up with a list of foods that all patients with diverticulitis should avoid. 

However, the following foods are associated with diverticulitis.

1. Red Meat

Avoiding red meat is a universal recommendation for people with acute diverticulitis. Several studies have linked red meat consumption with the condition.

Researchers in one study recommendless than 51 grams per day of red meat. This level is considered low risk for the development of diverticulitis. Red meat takes a long time to digest as it spends several hours moving through the colon. 

Also, red meat is a low-fiber food and can lead toconstipation. Constipation can cause pressure in the bowels, which can lead to the development of diverticula.

Another study also found an association between red meat intake,particularly unprocessed red meat, and an increased risk of diverticulitis. The scientists found that substituting even one serving of unprocessed red meat daily with poultry or fish decreased the risk of diverticulitis.

2. Refined Grains and High-Fat Dairy

One large study compared a typical Western diet high in red meat,refined grains, and high-fat dairy with a healthier diet high in fruits, vegetables, and whole grains. The conclusion was that a typical Western diet poses a risk for diverticulitis.

Refined grains and high-fat dairy are low in fiber. Low-fiber foods often cause constipation, which can increase pressure within the digestive tract, and therefore, an increased risk for the development of diverticula. 

3. What about Nuts and Seeds?

In the past, doctors used to tell patients not to eat seeds, corn, and nuts, as these foods are high in fiber, which can become stuck in diverticular pouches, leading to inflammation. However, recent research doesn't support the notion that these foods cause or worsen diverticulitis.

How Does Fiber Calm Down diverticulitis?

For many years, doctors advised patients to restrict their fiber intake and eat a restricted diet during an episode of diverticulitis. However, there is little evidence to support this practice, so it's being revisited.

Dietary fiber is found in whole grains, nuts, seeds, fruits, legumes, and vegetables. Some of this fiber is insoluble. It absorbs water and becomes part of feces - making the stools bulkier, softer, and easier to pass. This avoids pressure on the intestine walls because the person doesn't need to strain to pass a stool. Straining weakens the colon walls, which may lead to the formation of diverticula.

Findings from the Nurses' Health Study show that women who consume the most dietary fiber have alower chance of getting diverticulitis. Specifically, eating whole fruits (like apples, pears, and prunes) and cereal fibers is associated with a lower risk, while eating vegetables may not have the same effect.

Asystematic review published in 2018 included 5 studies investigating the role of dietary fiber during uncomplicated diverticulitis and an acute flare-up. The researchers commented that the current evidence for dietary management of acute, uncomplicated diverticulitis is limited and of low quality. They suggested more research is needed.

Despite this, the review suggests using regular diets instead of restricted diets for acute, uncomplicated diverticulitis. 

Furthermore, after a person has recovered, a high-fiber diet is strongly recommended. It could either be with or without fiber supplements, depending on an individual's nutrient needs. 

This is where a plant-basedfiber powder may come in handy, especially if you are looking to increase your fiber intake gradually. 

Do You Want High or Low Fiber for Diverticulitis?

In case of uncomplicated diverticulitis, you can follow your regular diet, which should include high-fiber foods.

During an acute episode, before recovery, a low-fiber diet is recommended. Your doctor may suggest a temporary hold on fiber intake while the condition is ongoing. If you have a mild, uncomplicated flare-up, your doctor may recommend avoiding solids for a short period so as to give your bowel some rest. 

During that time, you may drink clear liquids, follow a liquid diet, or eat only low-fiber food. 

As soon as the condition resolves, you must gradually revert to a high-fiber diet. Remember, in the long term, a high-fiber diet is good for the gut and may prevent future flare-ups.

You may feel bloated and gassy if you are not used to a high-fiber diet, but don't give up too soon. The discomfort usually disappears after some time. 

If you are not into high-fiber cereals, try whole-wheat bread. Also, all fruits and vegetables are high in fiber. Aim to increase your daily intake by about 5 grams per week until you reach the goal for your age and gender. 

What Foods are Best for Diverticulitis?

In case of a severe diverticulitis flare-up, it's best to follow a liquid diet. Then, gradually move on to a solid but low-fiber diet. On a low-fiber diet, you can enjoy the following foods:

  • White bread, white rice, and white crackers.
  • Cornflakes and puffed rice cereals.
  • Potatoes, mashed, baked, or roasted.
  • Eggs, any way you like them.
  • Tofu, chicken, lean ground turkey, and steamed fish.
  • Enjoy fruits but not with their skins at this stage.
  • Cottage cheese and Greek yogurt.

After the flare-up, you can start eating a fiber-rich diet. 


What Happens if Diverticulitis Goes Untreated?

Untreated diverticulitis can lead to serious complications that require surgery, such as abscesses, peritonitis, and scarring that leads to blockage of the intestine.

What's the Worst Thing for Diverticulitis?

A high-fat, low-fiber diet is the worst thing for diverticulitis. The key culprits are processed meat, red meat, fried foods, and full-fat dairy products.