Upon analysis, Staller and his team found that study participants following the Mediterranean or plant-based diets had a lower risk for developing chronic constipation.

“This finding highlights the potential for long-term adherence to diets rich in vegetables, nuts, and healthy fats to lower the risk of chronic constipation, independent of total fiber intake,” Staller said.

“It supports using whole dietary patterns, not just isolated nutrients, as preventive strategies. These diets may work by modulating the gut microbiome, increasing short-chain fatty acid production, and reducing systemic inflammation — all of which contribute to improved gut motility and function,” he said.

Additionally, researchers discovered that participants who followed the Western or inflammatory diet were more likely to develop chronic constipation.

What diets increase risk of constipation?

“Our data suggest that diets high in processed foods, red meats, and refined grains — common in Western and inflammatory diets — may increase the risk of chronic constipation. Although the mechanism by which these effects occur was not studied, these diets may promote gut inflammation and negatively affect gut microbiota, emphasizing the importance of limiting such dietary patterns for better gastrointestinal health.”
— Kyle Staller, MD, MPH

“We have hypothesized that the benefits of the Mediterranean diet may be mediated through its impact on the gut microbiome,” Staller continued.

“We would like to examine the microbiome profile among those consuming a Mediterranean diet who do not develop constipation with aging and compare it to those consuming a Western diet who do develop constipation. If these studies support a mechanistic rationale for the Mediterranean diet, we would pilot a feeding study to see if the Mediterranean diet can treat older adults who have already developed chronic constipation,” he added.

MNT had the opportunity to speak with Ashkan Farhadi, MD, a board certified gastroenterologist at MemorialCare Orange Coast Medical Center in Fountain Valley, CA, and author of The Rhymes of Happiness: Weaving Science, Art and Poetry in the Pursuit of Happiness, about this study, who commented this research helps validate what doctors know what to be right with data to back it up.

“When we get older, most of the movement in the body gets slower, and that does not exclude the colon,” Farhadi explained. “Many studies have shown as we grow older, the transit time in the colon is reduced in speed and frequencies. And it’s not surprising that people get more constipated as they get older.”

“The other factor that is also important in this equation is [a] busy lifestyle,” he continued. “One of the most common factors for constipation [i]s when you are busy, basically you ignore the urge, and after a while the colon gets tired sending messages and people get constipated.”

“To counter that, there are a couple of measures — one of them that is very important is diet,” Farhadi added. “And this study is a strong, important, fact-based piece of information that we can use to help to counter that constipation.”

MNT asked Monique Richard, MS, RDN, LDN, a registered dietitian nutritionist and owner of Nutrition-In-Sight, for her top tips on how readers can keep their bowel movement more “regular” and help lower their risk for chronic constipation.

“Constipation isn’t just about fiber — it’s about rhythm, hydration, movement, and microbiome love,” Richard explained. “Meeting with a registered dietitian nutritionist (RDN) can also explore the variables that could be addressed, including gut bacteria composition and metabolic pathways, as well as nutrient depletion, hydration status, and other physiological interference.”

For general tips in reducing constipation, Richard recommends:

• Incorporating a variety of three to five servings of whole grains daily, such as oats, amaranth, quinoa, millet, rice, buckwheat, and sorghum.
• Choose four to six servings daily of varying fruits and vegetables based on what’s local and in season.
• Hydrate throughout the day with water, herbal, or black and green teas.
• Add healthy fats when cooking, as snacks, or as toppers to a meal, such as olive oil to a saute, nuts, or nut butters with fruit for a snack, or topping a salad with sesame seeds or toasted walnuts
• Nourish the gut microbiota with foods rich in polyphenols such as berries, cocoa powder, and herbs and spices such as oregano, peppermint, sage, clove, and rosemary.
• The intestinal tract thrives with fresh oxygen flow and blood exchange — go for a walk, practice yoga, or participate in movement that you enjoy and can participate in on a regular basis, to help keep you regular.
• Low magnesium intake is associated with constipation, especially in older adults. Incorporate foods rich in magnesium, such as pumpkin seeds, almonds, dark leafy greens, avocado, and bananas.
• Prunes and kiwi can be a delightful way to prevent constipation — add a couple for a snack with some nuts or seeds.
• Make a meal with beans a few times a week; add lentils to sides and main meals; snack on roasted garbanzo beans or hummus.
• Be consistent with meal time — bodies thrive on a schedule that lets them rest and digest with plenty of time in between to clean up and disseminate nutrients. Try to keep mealtime around the same times every day for breakfast, lunch, and dinner, and plenty of time for rest between dinner and bedtime.

“Real food, regular meals, and rest are non-negotiables in supporting gut health and effective elimination,” Richard added. “The quality of input affects the output and everything in between.”