Diverticulosis/Diverticulitis: Causes, Symptoms, and Management
- Jitka Burger
- May 10, 2025
- 4 min read
Have you ever been told to avoid nuts, seeds, or popcorn because they could become trapped in diverticula and cause inflammation?
Good news: current research does not support this long-standing myth.
According to a study of 47,228 men followed for 18 years, consuming nuts and popcorn did not increase the risk of diverticulitis or diverticular bleeding. In fact, people who ate nuts at least twice per week had a 20% lower risk of diverticulitis, while popcorn consumption was associated with a 27% lower risk 1].
But let’s start at the beginning…
What Is Diverticulosis?
Diverticulosis occurs when small pouches called diverticula develop in the wall of the colon, most commonly in the lower left portion of the large intestine.
Most people with diverticulosis have no symptoms and may not even realize they have the condition until it is discovered during a colonoscopy or imaging study.
Why Do Diverticula Form?
Diverticula are thought to develop primarily because of increased pressure inside the colon.
This pressure is often associated with small, hard stools and constipation, which are commonly linked to low-fiber diets.
When stool lacks fiber:
it becomes smaller and harder,
moves more slowly through the intestines,
and requires more pressure to pass.
Over time, this pressure may weaken the colon wall and contribute to the formation of diverticula.
Risk Factors for Diverticulosis
Several factors may contribute to diverticular disease, including: 2], 3]
low fiber intake,
chronic constipation,
inadequate hydration,
lack of physical activity,
older age,
obesity,
diets high in highly processed foods.
Some studies suggest that diverticular disease is far less common in populations consuming traditional high-fiber diets.
However, researchers believe diverticular disease is likely influenced by multiple factors, including diet, genetics, aging, lifestyle, and the gut microbiome.
What Is Diverticulitis?
While diverticulosis often causes no symptoms, diverticulitis develops when diverticula become inflamed or infected, often after stool becomes trapped inside the pouches.
Diverticulitis can range from mild to severe and may occasionally lead to serious complications.
Symptoms of Diverticulitis
Common symptoms include:
abdominal pain, often in the lower left side,
bloating and cramping,
constipation or diarrhea,
fever and chills,
nausea and vomiting,
rectal bleeding.
Severe abdominal pain, fever, or rectal bleeding require prompt medical attention.
Diagnosing Diverticulitis
Doctors may use several tests to diagnose diverticulitis, including: 4]
blood tests,
stool tests,
ultrasound,
CT scan,
colonoscopy.
Management and Prevention
Managing diverticulosis and diverticulitis typically involves dietary and lifestyle changes aimed at reducing pressure in the colon and promoting healthy bowel movements.
Helpful Strategies
Increase fiber intake
Drink plenty of water
Exercise regularly
Limit highly processed foods
Avoid excessive straining during bowel movements
Fiber-Rich Foods
Foods naturally rich in fiber include:
fruits,
vegetables,
legumes,
oats,
whole grains,
chia seeds,
flaxseeds.
Gradually increasing fiber intake while maintaining adequate hydration may help soften stool and reduce pressure in the colon.
Complicated Diverticulitis
More severe cases of diverticulitis may require antibiotics, hospitalization, or surgery. In some cases, the affected portion of the colon may need to be surgically removed.
Diverticulitis also contributes significantly to healthcare costs and hospitalizations in the United States 5].
Emergency Visits and Hospital Admissions: Approximately 371,000 emergency department visits and 200,000 inpatient admissions occur annually in the United States.
Economic Impact: Annual healthcare costs are estimated at 2.1–2.6 billion dollars. In 2015, total expenditures related to diverticulosis and diverticulitis exceeded 5.4 billion dollars.
Increasing Incidence: The rate of diverticulitis continues to rise, contributing to increasing healthcare utilization and costs.
When to Seek Medical Attention
Seek immediate medical attention if you experience:
severe abdominal pain,
fever,
vomiting,
or rectal bleeding.
These symptoms may indicate diverticulitis or another serious gastrointestinal condition.
Conclusion
Diverticulosis is very common and often causes no symptoms. However, in some people it can progress to diverticulitis, which may become painful and potentially serious.
Although diverticula themselves usually do not disappear, dietary and lifestyle changes can significantly reduce the risk of inflammation, complications, and recurrent episodes.
A high-fiber, plant-based diet remains one of the most effective strategies for supporting colon health and helping prevent diverticular disease complications.
References:
1] Strate LL, Liu YL, Syngal S, Aldoori WH, Giovannucci EL. Nut, corn, and popcorn consumption and the incidence of diverticular disease. JAMA. 2008;300(8):907-914. doi:10.1001/jama.300.8.907
2] Painter NS, Burkitt DP. Diverticular disease of the colon: a deficiency disease of Western civilization. Br Med J. 1971;2(5759):450-454. doi:10.1136/bmj.2.5759.450
3] Crowe FL, Appleby PN, Allen NE, Key TJ. Diet and risk of diverticular disease in Oxford cohort of European Prospective Investigation into Cancer and Nutrition (EPIC): prospective study of British vegetarians and non-vegetarians. BMJ. 2011;343:d4131. Published 2011 Jul 19. doi:10.1136/bmj.d4131
Diet and risk of diverticular disease in Oxford cohort of European Prospective Investigation into Cancer and Nutrition (EPIC): prospective study of British vegetarians and non-vegetarians - PMC (nih.gov)
4] Destigter KK, Keating DP. Imaging update: acute colonic diverticulitis. Clin Colon Rectal Surg. 2009;22(3):147-155. doi:10.1055/s-0029-1236158
5] Peery AF, Crockett SD, Murphy CC, et al. Burden and Cost of Gastrointestinal, Liver, and Pancreatic Diseases in the United States: Update 2021. Gastroenterology. 2022;162(2):621-644. doi:10.1053/j.gastro.2021.10.017
