How often a person has a bowel movement—influenced by what they eat or drink or other lifestyle factors—affects their gut microbiome’s overall makeup, ultimately influencing disease risk. A recent study found that infrequent bowel movements drive the accumulation of toxic metabolites that impair kidney function.

The study involved more than 1,000 healthy adults. Researchers collected information about the participants' bowel movement frequency and lifestyles. They categorized the participants according to the frequency of their bowel movements: diarrhea, high-normal (one to three daily), low-normal (three to six weekly), or constipation. Then, they analyzed their gut microbial makeup and measured proteins and metabolites in their blood.

They found that participants with lower bowel movement frequency tended to be female, young, or thin and had gut microbial populations that mirrored those of people with Parkinson’s disease—who often have constipation. They also had high levels of blood metabolites associated with kidney dysfunction, neuroinflammation, cognitive decline, and vascular disease. These participants were more likely to report low fruit and vegetable intake, high snack intake, and anxiety and/or depression.

Frequent bowel movements may reduce the overall diversity of microbes in the gut, increasing the risk of inflammation and poor health. However, infrequent bowel movements may increase levels of toxic microbial metabolites in the urine, driving chronic kidney disease and neurodegenerative disorders.

These findings suggest that bowel movement infrequency alters gut microbial populations and increases the production of harmful metabolites. Fruits and vegetables contain bioactive compounds and dietary fiber that benefit gut health and promote regular bowel activity. This smoothie is a tasty way to get more fruits and vegetables into your diet.

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