Diverticular Disease - Symptoms, Diagnosis and Treatment

What is diverticular disease ? It is the formation of little pouches of gastrointestinal lining which bulge through the muscle of the colon wall. It is a bit like having lots of little hernias in your large intestine.

The intestinal walls are made up of many different layers. The inner most layers, the mucosa and the sub mucosa are delicate and weak and the muscle layers underneath are stronger and contract in order to push your stool along to the back passage and then out through the anus when you have a bowel movement.

Think of it a bit like a bicycle tire, with an inner tube and an outer tube. The muscular layers normally keep the delicate inner layer in position.

As we age however, the intestinal wall weakens and pressure against the wall can cause the inner layer to push through the muscle layer forming pouches called diverticula.

This is far more likely to happen if we have constipation, as when the stools are hard they exert far more force against the intestinal wall than when they are soft.

Diverticular disease - interior of the colon with openings to diverticulaThis is an illustration showing the openings leading to the diverticula. Photographs of a real bowel with diverticular disease look just like this.

Is a Diverticulum Like a Polyp?

No. Polyps are growths which stick out into the lumen (open space in the middle of the bowel) and can be pre-cancerous. Diverticula point the other way as they are just normal tissue pushed into the bowel wall to form a sac.

Who gets Diverticular Disease?

Diverticular disease is associated with age. As we age our intestinal wall becomes weaker and so we are more prone to this problem. It has been found that about 5% of forty year olds have diverticula pouches and about 50%-70% of 80 year olds.

For reasons that are not clearly understood you are also more at risk if you:

  • Smoke
  • Are overweight
  • Have a family history of diverticular disease
  • Take non-steroidal anti-inflammatory drugs (NSAIDs)
  • Do not exercise

Men and women are just as likely to get it but men tend to show signs at an earlier age.

It is very common in industrialized western countries but much less common in Africa and Asia.

Is Diverticular Disease Dangerous?

Many people with diverticular disease do not even know that they have it as they have no symptoms (asymptomatic diverticulosis) and often they only discover they have these pouches during a routine colonoscopy for something else. About 25% of people will have symptoms (symptomatic diverticulosis) which include:

  • Lower abdominal pain (particularly left sided)
  • Diarrhea
  • Constipation
  • Bloating and gas
  • Bleeding (slight-hemorrhage)

Left sided abdominal pain is more common than right because the most common location for diverticula is in the sigmoid colon which is on the left hand side of the body.

If you are of Asian descent however you are more likely for genetic reasons to have diverticula in the ascending colon which would give you pain on the right side.

It has recently been found that people with symptomatic diverticulosis have chronic inflammation similar to inflammatory bowel disease.

About 30% of people go on to have one or more episodes of diverticulitis. This is where the pouches become inflamed and infected and need treatment with antibiotics and a fasting diet to rest the intestines.

Twenty percent of people who have diverticulitis or inflammation of their diverticula will go on to develop complications, a fistula, perforation, peritonitis, obstruction and abscesses which may mean a hospital stay and even surgery.

So in answer to our question is diverticular disease dangerous? For most people it isn't but for a small percentage of people it can be, if a complication or diverticular bleeding occurs.

Diverticular Bleeding

Diverticular bleeding only occurs in about 5% of people with diverticular disease but when it happens it can be very spectacular and frightening. However, because diverticular disease is widespread in the population it is something which is commonly seen at the ER.

It happens because normally a diverticulum forms in a place where a blood vessel enters the bowel causing a weakness.

The blood vessel can become looped over the dome of the pouch. Pressure on the pouch weakens the blood vessel. Sometimes fecaliths (a hard concrete like mass of feces) can cause damage, with ulcers and erosions leading to perforation of the blood vessel.

It usually comes on suddenly and the bleeding can be very profuse with the passing of lots of bright red or darker red blood, usually with clots. It is usually painless.

If this happens to you it is important to call for emergency help immediately. When you reach the emergency room you will often require a blood transfusion. The good news is that in 80% of cases the bleeding will stop spontaneously.

If the bleeding does not stop then a colonoscopy will be done to find the source of the bleeding and stop it by injecting drugs directly into the bleeding blood vessel, using clips or bands or by cauterizing it. 

If the bleeding cannot be found on colonoscopy then a specialist x-rays will be done. In rare cases surgery may be needed.

The chance of diverticular bleeding increases with age and with obesity.

What Causes Diverticular Disease?

The exact cause is not clearly understood and research is ongoing but it is known that a history of constipation will make it more likely that you will develop this problem.

When you have constipation your stools are very hard and moving slowly or may even be stationary for a while, in fact sometimes they may be like small rocks or pebbles.

If there is a weak spot in the intestinal wall (usually where a blood vessel enters) as these hard 'rocks' and 'pebbles' push against it, maybe for quite some time, eventually the pressure will be too much and the lining will be pushed through the muscle to form a pouch or diverticulum.

As the incidence of diverticular disease is much lower in Africans than Europeans it has long been thought that their diet which is much higher in fiber protects the Africans, especially as African Americans have an incidence equal to white Americans. 

A study in 2012 published in the journal Gastroenterology however contradicted this as it found that the tested subjects had more diverticula if they ate a high fiber diet.

This is only one study though and more research needs to be done.

Another theory is that Africans tend to squat to open their bowels which automatically lessens the pressure in the colon and makes it easier to go.

To mimic this squatting position when having a bowel movement it is a good idea to put your feet up on something like a small stool, step or even a pile of books so the knees are higher than the hips and lean forward slightly.

How is it Diagnosed?

Tests are needed if you have symptomatic diverticular disease as the symptoms can overlap with many other problems like irritable bowel syndrome, appendicitis, ovarian cyst and cancer of the colon for example, so making a diagnosis using signs and symptoms alone can be difficult.

Although there is no specific blood test, blood tests would be done to look for signs of inflammation and anemia and to rule out things like celiac disease.

A special type of CT scan called a pneumocolon or colonography is one way of diagnosing the presence of diverticula. After your bowels are cleared by using a laxative, air is pumped into your rectum using a tube. This special x-ray gives a detailed picture of your colon and any diverticula present.

Sometimes a colonoscopy is done. This involves inserting a camera on the end of a tube so that the doctor can see the walls of the colon and notice anything abnormal. If you have diverticula he or she would be able to see the openings in the colon wall and rule out anything like colon cancer.

Occasionally a barium enema x-ray would be done but only if the other tests prove difficult for any reason as it is not as accurate. 

What Can I Do?

If you have a diagnosis of diverticular disease then the most important thing is to try and prevent any flare ups of diverticulitis.

The best way to do this is to try and keep your stools soft and bulky so that small bits of hard poop do not break off and get trapped in the pouches leading to inflammation and infection.

Preventing Constipation

To stop constipation taking hold:

  • Drink lots of liquids
  • Exercise - walking helps to get the bowels moving
  • Increase the fiber in your diet gradually
  • Do not take certain medications like codeine which have a constipating effect (check with your pharmacist if you take regular medication)
  • If you get the signal to open your bowels, do not delay, the signal will weaken if you put off going
  • Adjust your position when opening your bowels (Have your knees higher than your hips)  
  • Do not take traditional laxatives as they irritate the intestines, change the tone and feeling and are habit forming
  • Take bulking agents occasionally if you have to but not regularly as it is better to adjust your diet

A word about diverticular disease and diet. At the moment increasing the amount of fiber in your diet is recommended but this should be done gradually to avoid symptoms like excessive gas. This means eating more foods such as:

  • Vegetables
  • Fresh and dried fruit
  • Legumes like beans
  • Whole grains like brown rice and wholemeal bread
  • Nuts
Diverticular disease - fruit, vegetables and nuts

It used to be thought that eating certain foods like nuts, sweetcorn, popcorn, peas or fruits containing pips like strawberries and tomatoes would cause small particles to become trapped in the pouches and cause inflammation.

Doctors no longer give this advice but anecdotally some people still believe that their symptoms are made worse if they eat things which are not wholly digested and can get trapped in this way.

Bulking agents, (like Metamucil made from psyllium husk for example), increase the volume of the stool which becomes soft and gel like making it easier to go.

They should always be swallowed with extra water as there have been reports of obstruction and choking if fluid intake is not adequate.

Psyllium husk is now being added to many foods in the US to try and improve their health profile but think about the other ingredients as well. That carrot cake also has a lot of sugar and fat in it!

Pain Relief

To relieve abdominal pain take Tylenol (Paracetamol).

Do not take aspirin and ibuprofen as these drugs cause irritation in the gastrointestinal tract.

Many pain relief medications like codeine do cause constipation so be careful to check before taking anything.

If your pain gets worse seek medical attention in case it is something else and not your diverticular disease.

If You Have Diarrhea

Some people with diverticular disease suffer with diarrhea. If you have this symptom be very careful using standard anti-diarrhea medication like loperamide (Imodium) as this can easily tip you over into having constipation.

Try keeping a food diary to see if you are reacting to any particular food.

Try eating more foods containing soluble fiber. You can get more information about this in the article Foods To Stop Diarrhea.

Be careful to drink enough to replace fluids if you have frequent diarrhea. Oral rehydration therapy maybe needed if it is severe. See here for more information about dehydration.

Try taking probiotics (see below).


It has recently been discovered that people with symptomatic diverticulosis are more likely to have dysbiosis (imbalance of the gut flora).

It has therefore been proposed that restoring the correct balance to the gut flora by taking high quality probiotics and adding prebiotic foods to the diet could reduce inflammation in the gut and the diverticula.

My favorite prebiotic food is finely shredded raw leek added to sandwiches or salad!

Scientists are still undecided whether probiotic supplements can permanently colonize the colon as it can be hard to find them in fecal samples once you stop taking them but new findings have found that some strains have adhered to the lining (mucosa) of the gut when a sample is taken directly.

If your immune system is suppressed because you have had an organ transplant or you are receiving chemotherapy for example you should not take probiotics.

Living With Diverticular Disease

Unfortunately diverticular disease is not something which resolves but by careful management it is possible to reduce the diverticular disease symptoms and prevent complications.

My mother-in-law lived with this problem for years and she learned how to manage it to lessen the chance of symptoms happening.

Eating a constipation preventing diet is important but re-balancing your friendly gut bacteria could prove to be a therapy of the future.

If you have the symptoms of diverticular disease but are not sure what is going on please seek medical attention as these symptoms could be signs of other things like irritable bowel syndrome or colon cancer.

Please see below for more information about diverticulitis symptoms, complications and treatment.

Diverticulitis Symptoms and Complications

Diverticulitis symptoms - know when it is happening and when to call for medical help.

Go to Diverticulitis Symptoms and Complications

Diverticulitis Treatment Options - Home or Away?

Find out about the different options for treatment whether at home or as an in patient.

Go to Diverticulitis Treatment Options - Home or Away?

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