According to the results of a new study, the length of one’s fingers may be closely linked to their drinking habits. The study, carried out by researchers from Swansea University and the Medical University of Lodz, was published in the American Journal of Human Biology. Its findings showed that people with longer ring fingers relative to index fingers, which indicates high prenatal testosterone exposure, are more likely to consume alcohol.
The study’s participants included 258 university students who completed the alcohol use disorders identification survey which asked questions about their alcohol consumption habits. Moreover, this research also found that this relationship was more pronounced in men, who generally demonstrate higher alcohol consumption and related risks compared to women.
“Alcohol consumption is a major social and economic problem. Therefore, it is important to understand why alcohol use shows considerable differences across individuals,” said Professor John Manning, of Swansea’s Applied Sports, Technology, Exercise and Medicine (A-STEM) research team in a press release. “A pattern like this suggests an involvement of sex hormones, such as testosterone and estrogen. It is known that alcohol-dependent patients have very long 4th digits relative to their 2nd digits, suggesting high testosterone relative to estrogen exposure before birth. As expected, the associations were stronger for men than women.”
It is currently thought that estrogen and testosterone exposure in utero is reflected in the relative lengths of our index and ring fingers (second and fourth fingers), but this theory has also been contested by some scientists. Several other research studies have already shown a potential relationship between long ring fingers relative to index fingers and higher alcohol consumption. In addition, a large-scale online survey of self-measured finger lengths also revealed that national averages and individual values of digit ratios can predict alcohol consumption. Some previous research has already shown that the hormone testosterone creates changes in the brain and other organs in the fetus, which are activated in males by the spike in testosterone at puberty.
The study’s authors suggest that their findings could improve our understanding of how prenatal hormone exposure can influence behaviour, potentially helping to guide interventions for alcohol-related issues.
