Study finds correlation between oral microbiome, alcohol metabolism, and hangover severity

Hangovers are common among people who drink alcohol. Previous research showing that a hangover's combination of both mental and physical misery can occur after a single episode of alcohol consumption also revealed that a rapid breakdown of alcohol into acetaldehyde is associated with less severe hangovers. Findings from an investigation of the metabolic influence of oral microbiota on hangover severity will be shared at the 46^th annual scientific meeting of the Research Society on Alcohol (RSA) in Bellevue, Washington.

"We have been evaluating the causes and consequences of the alcohol hangover for more than 20 years," said Joris C. Verster, associate professor at Utrecht University, the Netherlands. "For this study, we looked at the microbiome, which refers to the community of microorganisms, such as bacteria, that live in the human body. More specifically, we evaluated the abundance of bacteria strains in the mouth, some of which are known to influence alcohol metabolism by accelerating the breakdown of alcohol into acetaldehyde."

Verster will discuss these findings at the RSA meeting on Sunday, 25 June 2023.

Verster and his colleagues conducted a naturalistic study, during which 15 healthy young adults had an unsupervised night of alcohol consumption. The next day, the "hangover day," participants were assessed for hangover severity, and saliva samples were collected. Another day was the "control day," during which no alcohol was consumed. Saliva samples were again collected. Partial correlations – controlling for estimated peak blood alcohol concentrations – between the abundance of oral microbiota and hangover severity were computed.

"Naturalistic study designs have an advantage in that they can closely mimic a real-life drinking occasion," said Verster. "On the hangover day, we found a significant correlation between the abundance of the Rothia bacterial strain and] having less severe hangovers. This finding is in line with the known capacity of Rothia to convert alcohol into acetaldehyde. We know that alcohol can freely cross the blood brain barrier to cause a hangover, while acetaldehyde cannot. Thus, we can assume that a quick conversion of alcohol into acetaldehyde prevents large amounts of alcohol to enter the brain, and as such, reduces hangover severity."

Alas, there are currently no hangover treatments marketed for which the efficacy and safety have been demonstrated," said Verster. "The best way to prevent a hangover is to moderate alcohol consumption."

Verster will present these findings, "The oral microbiome, alcohol metabolism, and hangover severity," during the RSA 2023 meeting in Bellevue, Washington on Sunday, 25 June 2023. More information can be found at RSoA on Twitter @RSAposts.