Q & A with Hangover Researcher Dr. Joris Verster

Toast! is based on clinical science, and when it comes to the science of alcohol and alcohol hangovers, Dr. Joris Verster is the leading authority. The author of dozens of publications on those topics, Dr. Verster is the founder of the Alcohol Hangover Research Group and principal investigator at the Division of Pharmacology at Utrecht University. Dr. Verster also serves as a scientific advisor for Toast!, and recently answered a series of questions from Toast! users.

The following Q&A was conducted by email with Dr. Joris Verster.

1: Is there a particular spirit that causes more severe hangovers? For example, tequila, and gin seem to be for me. I understand many factors go into a hangover, just want to see if a category or way alcohol is distilled has an influence.

Dr. Verster: Yes, there are differences between types of drinks and their impact on hangover severity. This difference is not caused by the amount of alcohol (ethanol) in the beverages, as this is standardized in many countries (e.g., in The Netherlands a standard unit of wine, beer or spirits all contain 10 gram alcohol). Instead, the effect is caused by so-called ‘congeners’. Congeners are other alcohols and substances that are formed during the distillation process of spirits. They give the drink its distinct flavor, color, and taste. The congeners can however aggravate hangover severity. Drinks with a high congener content such as tequila or cognac therefore can produce more severe hangovers than drinks with a low congener content such as vodka.

2: Are hangovers different for everyone?

Dr. Verster: Yes, the alcohol hangovers is a very personal experience. The alcohol hangover is defined as the combination of mental and physical symptoms that are experienced the day after an episode of heavy alcohol consumption, starting when blood alcohol concentration (BAC) approaches zero. However, there are a great number of hangover symptoms (a literature search identified around 50 symptoms!), including headache, sleepiness, apathy, and nausea. The presence and severity of these symptoms is hard to predict. They differ between drinkers, but also individual drinkers report that the presence and severity hangover symptoms vary from occasion to occasion.

3: Why are hangovers still so commonly blamed on dehydration?

Dr. Verster: The alcohol hangover is a very popular topic among drinkers, scientific research on the causes, consequences, and treatment of the alcohol hangover is limited. As a result, on the Internet several unproven theories on the pathology of the hangover are advocated, as well as many hangover treatments marketed without any scientific proof of their efficacy or safety.

One of the unproven theories is that hangovers are caused by dehydration. Indeed, thirst and dry mouth are often reported the day after a heavy drinking session. However, although drinking water may relieve these symptoms, other alcohol hangover symptoms persists. There is also no scientific evidence that drinking water during the drinking session or before going to bed will prevent having a next day hangover. It is therefore unlikely that hangovers are simply caused by dehydration. Current research suggests that its more likely that the immune system is involved in the development of alcohol hangovers.

4: What was the most surprising, for you, finding you've discovered while researching alcohol/hangovers?

Dr. Verster: When I started doing research on hangovers I was most surprised that so few researchers were conducting research in this area. While many researchers investigate the acute effects of alcohol consumption (e.g. intoxication), next day effects were largely neglected.

The socioeconomic and health consequences of the alcohol hangover are significantly underestimated by both the research community and policymakers. Absenteeism and presenteeism at work come at a high cost, and impairment of daily activities such as driving a car increases the risk of accidents and injury. The general public is well-informed about the negative alcohol intoxication effects, but often unaware about the negative impact of alcohol hangover effects.


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