Diverticulosis Diet: Should Nuts, Seeds, and Popcorn Be Avoided?

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Diverticulosis involves abnormal outpouchings from the wall of our colon, affecting most people by the time they reach their 60s whether they know it or not. In as many as 10 to 25 percent of individuals, these outpouchings can become inflamed and turn the diverticulosis into diverticulitis, resulting in hundreds of thousands of ER visits and hospitalizations, and sometimes even leading to perforation of the colon, which may have a fatality rate as high as one in five. But it wasn’t always like this.

Diverticulosis only became a problem in the 20th century. What is now a massive epidemic didn’t even start showing up in medical textbooks until 1920. Diverticulosis appeared to be a deficiency disease of Western civilization. Just like scurvy is a deficiency disease caused by a lack of vitamin C, diverticulosis may be a deficiency disease caused by a lack of fiber.

Bowel movements should be effortless, but when we don’t get enough fiber-containing foods in our diet, like whole grains and beans, we have to strain to push unnaturally firm stools. The pressure necessary to force along small, hard stools may essentially blow pouches out of the wall of our colon, like when you squeeze one of those gel stress balls.

As we got better and better at refining grains and stripping away the fiber, diverticulosis rates shot up to epidemic levels. What about populations like those in rural Africa, where they were eating up to the triple digit grams a day that we as a species were meant to get, based on Paleolithic diet estimates and Paleopoo fossilized feces? Diverticulosis remained almost completely absent in areas that continued to center their diets around whole plant foods, the only foods where fiber is found in abundance. So, just like heart disease is the number one killer in the United States, and was virtually unknown in rural Africa, diverticulosis was also virtually unknown––whereas it’s the most common disease of the colon here and around the Westernized world.

Migration studies prove it’s not just some genetic racial difference either. The prevalence of diverticulosis was one percent in Japan. At the same time, it was 50 times higher in Japanese people who started eating and living like Americans. Higher fiber intake may also explain why vegetarians may be up to nearly three times less likely to be affected by this condition.

Today, increasing fiber intake is accepted as the overriding dietary recommendation for people afflicted with diverticulosis. But what about the common advice from doctors telling patients with the condition not to eat nuts, seeds, and corn?

The rationale was that these foods could get lodged in one of the outpouching pockets and trigger inflammation, but the myth that we should avoid eating nuts, corn, popcorn, and seeds to prevent episodes of diverticulitis has been debunked with modern data. In fact, Harvard researchers looked into this and actually found protective associations between nut and popcorn consumption and the risk of diverticulitis. So, doctors should be telling patients with diverticulosis that they can eat nuts, corn, and popcorn without fear––advice echoed by Harvard, by the Mayo Clinic, and the Cleveland Clinic, where the avoidance advice was identified as the #1 myth. A healthy high-fiber diet is actually the best medicine against diverticulitis, and nuts and seeds certainly fit the bill. In fact, increasing dietary fiber intake should be seen as a major public health issue that may have a dramatic beneficial effect in diet-related diseases and deaths in general. In other words: eat more plants.

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Motion graphics by Avo Media

• beans
• bowel movements
• colon health
• diverticulitis
• fiber
• grains
• heart disease
• inflammation
• nuts
• popcorn
• seeds