Study suggests regular Laxative use linked to higher risk of Dementia

According to a new study published in the journal Neurology, older adults who regularly take laxatives could face a 51% higher risk of developing dementia than those who do not. Researchers from the University of Cambridge, Harvard Medical School, and other universities analyzed data from over 500,000 participants between the ages of 40 and 69 with no history of dementia.

Among those who said they took laxatives on most days of the week over the last four weeks, 1.3% had suffered from all-cause dementia or vascular dementia after an average of 9.8 years. Only 0.4% who did not use any laxatives had the same outcome.

Vascular dementia is a state that causes problems with reasoning, planning, judgment, memory & other thought processes caused by brain damage from impaired blood flow to your brain, as defined by the Mayo Clinic. The study found no association between laxative use and Alzheimer’s disease, making up most dementia cases.

The study also found that osmotic laxatives had the strongest link with dementia risk, with a 64% increase. Those who took various types of laxatives were found to have an even higher risk of dementia, with a 90% increase. Researchers rearranged the results to account for lifestyle factors, pre-existing medical conditions, medications, family history, and other socio-demographic attributes.

What the doctors say about it

According to Dr. Feng Sha, one of the study authors, regular use of over-the-counter laxatives could change the microbiome of the gut, affecting nerve signaling from the gut to the brain or increasing the production of intestinal toxins that may hamper brain activities. She suggests that medical professionals encourage people to treat constipation by making lifestyle changes such as drinking more water, increasing dietary fiber, and adding more activity to their daily lives.

While Dr. Laura Purdy, a board-certified family medicine physician, agrees that the study is high-level and only broadly looks at the association between dementia and laxative use, she believes more information is needed. She suggests that researchers should investigate which laxatives may contribute, how much use is risky, and what clinical recommendations should or shouldn’t be made regarding laxative use.

Dr. Marc Siegel, a professor of medicine at NYU Langone Medical Center, believes that the association between laxatives and all-cause dementia makes sense due to electrolyte disturbances with chronic laxative use and how laxatives draw chemicals out of the gut that works as neurotransmitters in the brain.

The study raises concerns for the millions of people who suffer from constipation in the US, leading to 2.5 million doctor visits yearly. The National Institute on Aging states that about one-third of older adults experience at least occasional constipation. The researchers proposed their hypothesis on the microbiome-gut-brain axis, which links the body’s intestinal functions with the brain’s cognitive centers.

If the findings are established, medical professionals could encourage people to treat constipation by making lifestyle changes such as drinking more water, increasing dietary fiber, and adding more activity rather than relying on regular laxative.