Use of an Antibacterial Mouthwash Alters the Gut Microbiome, Reduces Nutrient Absorption and Attenuates Diet-induced Obesity

Prolonged use of antibacterial mouthwash is linked to increased risk of systemic disease. We aimed to investigate if disturbing the oral microbiota would impact the lower gut microbiome with functional effects in diet-induced obesity. Mice were exposed to oral chlorhexidine and fed a Western diet. Food intake and weight gain were monitored, and metabolic function, blood pressure and microbiota were analyzed.


Chlorhexidine reduced oral bacteria and altered parts of the gut microbiota known to be associated with metabolic pathways. Chlorhexidine reduced weight gain, body fat, steatosis, and plasma insulin without changing caloric intake, while increasing colon triglycerides and proteins demonstrating reduced absorption of these nutrients. The mechanisms behind these effects as well as the link between the oral microbiome and small intestinal function need to be pinpointed.


While short-term effects of chlorhexidine in this model appear beneficial, potential long-term disruptions in the oral and gut microbiota and possible malabsorption should be considered.



Published: 07 Nov 2023

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