If you suddenly develop a fever, stomach pain, cramping, and nausea, you may assume you have a bad case of the flu.
But if the pain and cramping are localized to your lower left abdomen, you may want to head to the hospital. It could be diverticulitis, a rare but serious medical condition caused by inflammation in your large intestine and digestive tract.
While diverticulitis is rare, it’s become more common over the past several decades, and it’s potentially life-threatening if you do get it. The good news is that a healthy diet and other lifestyle changes may reduce your risk of developing diverticulitis.
Read on to find out what diverticulitis is, and how a high-fat diet like the keto diet may help you prevent it.
Diverticulitis is a rare condition caused by inflammation to your digestive tract — namely, your large intestine.
So, how does diverticulitis happen? It’s tough to talk about this condition without talking about a related condition called diverticulosis.
Diverticulosis is when a defect in the thick muscular layer of your colon causes the thin inner layers to bulge out, forming a sac-like pouch called a diverticulum (plural: diverticula).
It may sound scary, but diverticula are usually harmless. It’s normal to develop them as you age, and they don’t cause symptoms or problems in most people.
However, in rare cases, diverticula can become inflamed and infected, leading to diverticulitis. If left untreated, the inflamed diverticula can flare up, tear, and spread infection, which can be potentially life-threatening.
Risks of Diverticulitis
Complications of diverticulitis include[*]:
- Perforation: A small hole or tear in a diverticulum.
- Abscesses: A painful and swollen pocket of pus that causes abdominal pain, nausea, vomiting, and fever. Abscesses from diverticulitis can also be found in distant locations such as the liver, lungs, brain, and spine. If severe enough, abscesses need to be drained.
- Pylephlebitis: The inflammation of the renal portal vein, the blood vessel that carries blood from the gastrointestinal tract and spleen to the liver. Pylephlebitis can cause life-threatening blood clots.
- Bowel obstruction: Partial or total blockage of the movement of stool or food.
- Bleeding: Diverticula tend to occur in areas where blood vessels penetrate the muscular layer of the colonic wall. If a diverticulum gets infected, it can put you at risk for internal bleeding.
- Fistula: A fistula is an abnormal connection between organs. In diverticulitis, an abscess can breach the wall of a nearby organ, allowing bacteria and intestinal contents to enter organs such as the gallbladder, uterus, ureter, and vagina.
- Peritonitis: A diverticulum can rupture, resulting in a painful infection in the abdomen. Peritonitis is a life-threatening emergency that may require surgery.
The good news is that diverticulitis only affects between 1% and 5% of people with diverticulosis[*]. That means it’s highly unlikely that you will ever suffer from diverticulitis.
Diverticulosis (the precursor to diverticulitis) is common and usually harmless. It mainly affects people over the age of 40. An estimated 60% of all Americans will develop the condition by the time they reach age 60. And 71% will have it by age 85[*][*][*].
Diverticulitis can be severe in people of any age, but like diverticulosis, it tends to be more serious in older people, especially if you’re taking corticosteroids or other medications that suppress your immune system[*].
When it comes to gender differences, diverticulitis risk depends heavily on age.
Diverticular disease is becoming more and more common, but its exact cause is still unclear.
That said, there are three main theories about what causes diverticulitis.
#1: Low-Fiber Diet
Scientists think fiber deficiency is a major reason for the increase in diverticulitis over the last few decades.
The hypothesis linking diverticulosis and fiber originated in 1971 when two scientists saw that the condition was virtually nonexistent among Ugandans, who ate a fiber-rich diet[*].
Fiber softens stools and makes them easier to pass. If you don’t eat enough fiber, you may experience constipation and pressure in parts of your colon.
Muscles in the colon have to work much harder to pass hard stool, and the forceful contractions can cause diverticula to form.
This seems pretty cut-and-dry — if you eat more fiber, you prevent diverticulosis, and therefore prevent diverticulitis.
However, results from clinical trials have been inconsistent. Some studies found that a high-fiber diet was beneficial, while others showed that increased fiber intake had no effect on diverticulosis[*][*][*].
One 2014 study even showed that a high-fiber diet was actually associated with a higher, not lower, prevalence of diverticula[*].
This means that even if you eat a high-fiber diet, you can still develop diverticulosis.
Nonetheless, doctors and medical organizations continue to recommend high-fiber foods for patients with diverticulosis. While it may not be able to stop diverticula from forming, a high-fiber diet, along with an anti-inflammatory diet, could reduce your risk of diverticulitis[*].
Which brings us to chronic inflammation.
Chronic inflammation may also contribute to diverticulitis.
Inflammation isn’t inherently bad for you. You want inflammation at certain times — to attract white blood cells to a wound and help it heal, for example.
But if your inflammatory pathways are active all the time (chronic inflammation), you can run into health problems.
Many of the risk factors for diverticulitis are also notoriously associated with chronic, systemic inflammation. Here are a few:
- Obesity, high insulin levels, and poor blood sugar control[*][*][*][*]
- Smoking (particularly in complicated diverticulitis)[*][*][*]
- Western diet (high in bad fats and refined sugar, low in fiber)[*][*]
- Sedentary lifestyle[*][*][*]
- History of nonsteroidal anti-inflammatory drug (NSAID) use[*][*][*][*]
- History of opiate and corticosteroid use[*]
- Low vitamin D levels[*]
- Immunosuppression (ex: chemotherapy)[*]
People with diverticulitis have inflamed colons, and the degree of inflammation correlates with the severity of the condition[*].
Researchers suspect a cause-and-effect relationship: that inflammation causes changes in your colon, potentially causing diverticula to form at weak spots in your colon’s lining[*].
This means that the more inflamed your colon is, the more severe diverticular disease becomes. The good news is that there’s a lot you can do to prevent chronic inflammation.
Altered Gut Microbiome
The trillions of bacteria in your gut are work together in a careful balancing act.
Ideally, you have lots of good gut bacteria that help your body instead of hurting it. But if bad gut bacteria start taking over, you can develop an imbalance in your gut microbiome (called gut dysbiosis) that can lead to a variety of health problems, possibly including diverticulitis[*].
This is still a theory in its early stages, but researchers do know that small intestinal bacterial overgrowth (SIBO) — rapid growth of bad bacteria that overwhelm your small intestine — affects most patients with diverticulitis[*].
The theory is that tiny tears in the wall of a diverticulum allow pathogenic gut bacteria to get through your colon’s mucosal barrier and infect surrounding tissue[*].
On the other hand, good bacteria seem to be able to protect you from diverticulitis by decreasing inflammation and fighting off pathogens in your colon[*].
It’s difficult to determine a causal relationship between diverticulitis and any of the factors discussed above. That said, fixing the above issues is good for your health overall, and may protect you from diverticulitis as well.
Diverticulitis can be divided into two categories — acute diverticulitis and chronic diverticulitis.
- Tenderness of abdomen
- Stomach cramps
- Fever and chills
- High white blood cell count (leukocytosis)
- Change in bowel habits
- Nausea and vomiting
- Diarrhea (less common than constipation)
- Blood in stool
- Frequent and/or painful urination
Some people may have a single acute episode and never experience symptoms again. On the other hand, some people suffer from recurrent episodes that are separated by symptom-free periods.
While symptoms of acute diverticulitis are usually relieved by antibiotics and/or surgery, there are cases in which the symptoms never clear up completely. When this occurs, patients are diagnosed with chronic diverticulitis.
- Abdominal pain that persists for months, often without abdominal tenderness
- High white blood cell count
- Bowel obstruction
- Changes in bowel movements and stool appearance (usually narrower)
- Nausea and vomiting
- Mood changes, depression, anxiety
Doctors sometimes confuse diverticulitis with irritable bowel syndrome (IBS) because the symptoms are so similar.
It’s challenging to separate the two, especially because patients with acute diverticulitis may be at risk for developing IBS later on[*]. If you have IBS, you may want to get checked for diverticulitis.
#1: Reduce Inflammation
A ketogenic diet decreases chronic inflammation.
When your body enters ketosis — burning fat instead of carbs — it makes compounds called ketones. And there is mounting evidence that ketones are powerful superheroes in the fight against inflammation.
- Reducing the production of reactive oxygen species (ROS)
- Strengthening your mitochondria (the power plants of your cells)
- Triggering the growth of new mitochondria
- Increasing your body’s antioxidant production
- Increasing the availability of ATP (energy) within cells
- Turning off major inflammatory pathways
Keto helps you fight inflammation, which could decrease your risk of diverticulitis.
#2: Feed the Good Bacteria
Your diet and lifestyle choices can affect your gut microbiome. A high-carb, high-fat Western diet (think fast food) is linked to decreased microbial diversity, which is a sign of poor overall gut health[*][*][*].
The good news is that a keto diet supports your good gut bacteria. That’s because vegetables are your main sources of carbs in a keto diet.
Vegetables are rich in prebiotic fibers that feed good gut bacteria[*]. Fermented foods like sauerkraut and kimchi also strengthen your gut biome.
#3: Increase Workout Intensity
When you burn fat on a keto diet, you’ll enjoy a steady flow of energy since your body is not relying on sugar spikes. You can then use this boost of energy to increase the intensity of your workout and reduce your risk of diverticulitis.
One large study followed 9,072 men and 1,664 women over 7.7 years to observe the effect of running on the likelihood of developing diverticular disease.
Of the people who developed diverticular disease, researchers found that[*]:
- People who ran an average of over 8 km daily had a 48% lower risk than those who ran less than 2 km per day
- Each km-per-day increment in running distance was correlated with a 6.2% decrease in risk for diverticular disease
- People who ran faster than 4 m/s in a 10-km running distance had 70% lower risk compared to those who ran slower than 2.8 m/s
These results suggest that high-intensity cardio may help prevent diverticulitis. High-intensity training is also especially good for weight loss, which can decrease risk of diverticulitis if you’re overweight.
It’s worth mentioning that this study only examined the effects of running and jogging. Researchers don’t know yet how other types of workouts affect the risks of developing diverticular disease.
The Takeaway: Is a Keto Diet Good for Preventing Diverticulitis?
A well-formulated keto diet can be great for your health. Keto can help you manage several of the risk factors for diverticulitis, including obesity, chronic inflammation, gut dysbiosis, and high sugar intake.
But diet alone won’t help prevent diverticulitis. A combination of real food and healthy fats, regular exercise, a healthy gut microbiome, high-quality supplements, and strong mental health can help lower your risk even further.
Keep in mind that this is not medical advice. If you believe you’re at risk of developing diverticular disease, or if you’ve experienced recurrent diverticulitis attacks, work with your doctor to develop a treatment plan tailored to you.