New Study: Here’s How Often You Should Poop To Reduce Your Alzheimer’s Risk

Updated: Jan. 27, 2024

Compelling new research from Harvard suggests your time on the toilet might influence your brain health.

Maybe you’ve heard someone say they do their best thinking in the bathroom…and as comical as it might sound, science shows there may actually be a link. A new preliminary study conducted by Harvard researchers sheds light on the intriguing connection between the frequency of bowel movements and cognition.

More fascinating proof of the gut-brain relationship

First, a little background: The human gut, which some medical practitioners refer to as the “second brain,” is home to trillions of bacteria that play a vital role in many bodily functions, including digestion, immune response, and even mood regulation. A regular number-two ensures a healthy balance of these gut bacteria.

According to the National Institutes of Health, about 16% of adults have symptoms of constipation—a percentage that increases to 33% for groups aged 60 years and older. Factors like fiber-deficient diets, reduced physical activity, and certain medications can compound the problem.

When constipation becomes chronic—defined as having bowel movements less often than every three days—it’s not just a mere discomfort. This is associated with long-term health challenges, ranging from inflammation and hormonal imbalances to mental health concerns like anxiety and depression. A well-functioning digestive system ensures the efficient elimination of waste products, including those that can be toxic or harmful to brain function.

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The research breakdown

The Harvard research was presented at the Alzheimer’s Association International Conference in Amsterdam, Netherlands, in July 2023 by study author Chaoran Ma, MD, PhD, assistant professor of nutrition at the University of Massachusetts Amherst and former research fellow at Harvard. Dr. Ma led a team who explored the gut-brain axis by evaluating data from three cohort studies that tracked more than 110,000 participants’ bowel movement frequency and their cognitive functions. What emerged from the data was remarkable.

Those with infrequent bowel habits had cognitive abilities that equated to three years more of chronological cognitive aging. Meaning: If you’re constipated (experiencing bowel movements every three days or less), your cognitive function might decline, akin to aging your brain by three more years. This bowel movement infrequency was linked with 73% higher odds of subjective cognitive decline.

It wasn’t just about the number of trips to the restroom—the research further reveals some fascinating microbiological details: An uptick in bowel movements (more than twice a day) also hinted at an increased risk of cognitive decline. Participants who lacked certain gut microbes, especially those producing butyrate and those digesting dietary fibers, were in double jeopardy of reduced bowel movement frequency and cognitive function.

If you don’t experience daily bowel movements, making extra sure you’re getting proper nutrition may be something to think about.

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The takeaway for you

Dong Wang, MD, ScD, the study’s senior investigator and assistant professor of medicine at Harvard, offered a clear message: “These results stress the importance of clinicians discussing gut health, especially constipation, with their older patients.” He emphasizes that to maintain a healthy gut and, by extension, a healthy mind, one should “adopt diets enriched with high-fiber and high-polyphenol foods like fruits, vegetables, and whole grains; consider fiber supplementation; ensure ample daily water intake; and engage in regular physical activity.”

While the research continues, growing evidence highlights the significant role of gut health in fostering a keen, active mind. As you strive for mental clarity, remember that it might begin with good gut health.

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