In 2018, researchers tested 50 students to see if alcohol could improve foreign-language speaking; the surprising finding won an Ig Nobel Prize

What happens when someone who is nervous about speaking a foreign language has a drink first? A small experiment involving 50 German-speaking Dutch learners found that a low dose of alcohol was linked to better observer-rated pronunciation, while the drinkers themselves did not think their language skills had improved. Years later, the unusual study earned its researchers the 2025 Ig Nobel Peace Prize.

The finding may sound like the beginning of a joke, but researchers from Maastricht University and collaborating institutions decided to test it scientifically. Their 2018 study examined whether a small amount of alcohol could affect the way people speak a language they had recently learned.

The study, titled “Dutch courage? Effects of acute alcohol consumption on self-ratings and observer ratings of foreign language skills,” was published in the Journal of Psychopharmacology by Fritz Renner, Inge Kersbergen, Matt Field and Jessica Werthmann.


The experiment found something unexpected: people who consumed a low dose of alcohol were judged by independent native speakers to have better overall Dutch, with the clearest improvement appearing in pronunciation.

The participants themselves, however, did not think they had become better speakers.

Why did researchers test alcohol and foreign-language skills?

The idea grew from a familiar observation: people sometimes feel more confident speaking another language after drinking.

Alcohol can reduce inhibition and anxiety, but it can also affect attention, memory and motor skills. That created an interesting scientific question. Does alcohol actually improve foreign-language performance, or does it merely make people feel more confident?

50 German speakers were asked to speak Dutch

The study involved 50 native German-speaking undergraduate psychology students at Maastricht University who had recently learned Dutch. Participants were randomly assigned to two groups. Twenty-five received an alcoholic drink containing vodka and bitter lemon, while 25 received water as a control.

The researchers targeted a blood alcohol concentration of approximately 0.4 g/kg. Maastricht University said that for a 70-kilogram man, the dose was roughly equivalent to 460 millilitres of 5% beer.

After consuming their drinks, participants had a standardized conversation in Dutch with an experimenter who did not know whether they had received alcohol or water. The conversations were recorded.

Native Dutch speakers judged their performance

The researchers then asked two native Dutch speakers, who were unaware of the participants' drinking condition, to assess the recordings. Participants also rated their own Dutch.

This allowed the researchers to compare self-perception with independent judgment and the difference was striking.

The alcohol group received a significantly better overall observer rating for their Dutch. Their mean score was 61.53, compared with 56.65 for the water group (p = .02).

Pronunciation was the biggest difference

The researchers assessed pronunciation, grammar, vocabulary and argumentation separately and the clearest significant difference was pronunciation.

The alcohol group received an average pronunciation score of 6.72, compared with 6.27 for the water group. The difference reached statistical significance with an effect size of 0.66.

The study did not show that alcohol makes people better at vocabulary or grammar. Its strongest finding concerned how well their Dutch pronunciation was perceived by listeners.

The drinkers did not think they had improved

If alcohol simply made participants overconfident, the drinking group should have rated its own Dutch much more highly. That did not happen.

Self-rated Dutch performance averaged 55.53 in the alcohol group and 53.59 in the control group. The difference was not statistically significant.

In other words, the participants did not walk away thinking, “I suddenly speak Dutch brilliantly”, instead, the independent listeners were the ones who detected the difference.

Why might alcohol have affected pronunciation?

The researchers suggested that reduced social anxiety and inhibition could be one possible explanation.

Speaking a foreign language can make learners self-conscious. They may worry about pronunciation, grammar or being judged. A small amount of alcohol could reduce some of that anxiety and allow them to speak more freely. But the study did not prove this mechanism.

The researchers themselves emphasized that more work would be needed to determine exactly why the difference occurred. They also warned that a higher level of alcohol consumption could produce very different results.

From unusual experiment to Ig Nobel Peace Prize

The study's unusual subject eventually earned its authors the 2025 Ig Nobel Peace Prize.

The Ig Nobel Prizes celebrate scientific achievements that are initially amusing but can prompt people to think about serious questions. The award citation recognized Renner, Kersbergen, Field and Werthmann for showing that drinking alcohol sometimes improves a person's ability to speak a foreign language.

The researchers' question itself reportedly grew from informal observations and jokes about whether people speak foreign languages better after drinking. Instead of settling the argument at the bar, they put it into a laboratory.