Can Frequent Laxative Use Increase Dementia Risk?
Our primary care doctors in Delray Beach have been receiving questions from some of our patients about a recent study showing that those who regularly use laxatives may have an increased risk of dementia.
First, let us assure you that the study in question did not prove that laxatives cause dementia. It only showed an association.
Researchers at the University of Cambridge and Harvard Medical School reviewed self-reported data from more than 500,000 adults ages 40 to 69 in the U.K. who are registered in the UK Biobank database.
None of the subjects had dementia at the start of the study, which lasted 10 years. Of those who reported using laxatives, 1.3 percent developed dementia over the course of the study. Of those who did not use laxatives, 0.4 percent went on to develop dementia. This represents a more than 50 percent increased risk of dementia in the laxative group.
And it turned out that using more than one type of laxative increased overall risk. Those who regularly used two or more types had a 90 percent higher risk of dementia.
The researchers also looked at the risk of different types of laxatives. Those who used the osmotic types, which draw extra water to the colon to soften stool, were 64 percent more likely than others to develop dementia. Other types of laxatives include stimulating and bulk-forming.
“Regular use of laxatives, even without short-term severe adverse events, may have the potential long-term risk of dementia, especially when it comes to osmotic laxatives and combination use of two or more types of laxatives,” study author Feng Sha, an associate professor at the Shenzhen Institute of Advanced Technology at the Chinese Academy of Sciences in China, said in a news release.
The researchers weren’t sure what might account for the apparent correlation between dementia and laxative use.
“Regular laxative use may change the microbiome of the gut, possibly affecting nerve signaling from the gut to the brain or increasing the production of intestinal toxins that may affect the brain,” Sha said, adding that laxatives may also disrupt the gut-brain axis, allowing some microorganisms to reach the brain.
Other experts weren’t convinced the study, published in February in the online issue of Neurology®, the medical journal of the American Academy of Neurology, had enough information to draw reliable conclusions.
“Laxatives do change the microbiome, but we don’t have data to suggest that those changes caused by the laxatives are the same changes that we see in the study of dementia,” Dr. Ali Rezaie, director of the GI Motility Program at Cedars-Sinai Medical Center, told CNN.
He said the study period was not long enough, the data were self-reported which might mean participants’ memories were faulty, and that there wasn’t enough information on possible mitigating factors like fiber intake and the severity of the participants’ constipation.
Even the study’s lead author noted the need for further research.
“This finding requires confirmation by further studies before more actions should be taken,” Sha said.
Regardless, regular use of over-the-counter (OTC) laxatives isn’t a good idea.
The Mayo Clinic cautions that regular use of laxatives may cause you to become dependent on them for a bowel movement. In addition, they may interact with some antibiotics, along with certain heart and bone medications.
Finally, they can be dangerous if your constipation is caused by a serious condition such as appendicitis or bowel obstruction.
At best, laxatives can disrupt the gut microbiome.
“Laxatives may also flush out some of the good microbes from the gut, disrupting the balance of good and bad bacteria,” Yuko Hara, director of aging and Alzheimer’s prevention at the Alzheimer’s Drug Discovery Foundation in New York City, told U.S. News.
Treating constipation starts with getting more fiber in your diet through fruits and vegetables or fiber supplements, Dr. Aditya Sreenivasan, a gastroenterologist at Lenox Hill Hospital in New York City, told U.S. News.
“You also need adequate water intake and exercise because when you don’t move, your bowels don’t move,” he explained.
“Try these three things to see if you can get off laxatives,” he said.
What Else Can Help
The Cleveland Clinic suggests these additional ways to relieve constipation.
- Drinking water
The National Academies of Science, Engineering, and Medicine recommends the following daily fluid intake:
125 ounces (3.7 liters) for men
91 ounces (2.7 liters) for women
“Drinking lots of water, especially warm or hot water in the morning, can help you have a bowel movement,” Samita Garg, M.D. says.
2. Drinking coffee
Caffeinated coffee is especially notable for its laxative effect.
“Coffee can stimulate colonic contractions and the gastrocolic reflex, which cause increased movement of the lower GI tract in response to the stretch of the stomach from eating or drinking,” Garg says.
3. Increasing magnesium
In addition, foods high in magnesium will also help stimulate the bowels. Most of these are also high in beneficial fiber. These include:
- dark leafy greens
- nuts, especially almonds, cashews, and peanuts
- dark chocolate
- legumes, especially black beans
- potatoes with skin
The average adult should get between 25 and 31 grams of fiber per day, the Mayo Clinic says.
If none of these changes help, or if you’ve had changes to your bowel habits, be sure to let us know.