How long ring fingers can point to a love of alcohol

There is evidence that alcohol consumption is influenced by prenatal sex steroids so experts from Swansea University and colleagues from the Medical University of Lodz decided to use a sample of students for their research into the subject.

Their findings have just been published by the online journal American Journal of Human Biology. They found relationships between high alcohol consumption and long 4^th digits relative to 2^nd digits. This showed that high prenatal testosterone relative to oestrogen is linked to high student alcohol consumption.

Professor John Manning, of Swansea's Applied Sports, Technology, Exercise and Medicine (A-STEM) research team, said: "Alcohol consumption is a major social and economic problem. Therefore, it is important to understand why alcohol use shows considerable differences across individuals."

The study used a sample of 258 participants -- 169 of them female -- and it revealed consumption rates varied between the sexes. In comparison to women, men show higher alcohol consumption and higher mortality from alcohol abuse.

He said: "A pattern like this suggests an involvement of sex hormones, such as testosterone and oestrogen. Digit ratio (2D:4D: the relative lengths of the 2^nd [index] and 4^th [ring] fingers) is thought to be an index of early testosterone (long 4^th digit) and oestrogen (long 2^nd digit).

"It is known that alcohol-dependent patients have very long 4^th digits relative to their 2^nd digits, suggesting high testosterone relative to estrogen exposure before birth. As expected, the associations were stronger for men than women."

Now the researchers hope their conclusions will bring a better understanding of the factors underlying the pattern of alcohol consumption, from abstinence to occasional use to harmful dependence.

This is the latest paper which has highlighted Professor Manning's work in the field of digit ratios. Previous research has examined how digit ratio may provide vital information concerning outcomes after contracting Covid-19, as well as oxygen consumption in footballers.