That overwhelming drive to consume mass quantities of very strong coffee might actually have a biological component, because scientists in Italy say they’ve identified a gene that makes people inclined to drink lots of coffee.
According to The Local, scientists analyzed the coffee-drinking habits and DNA from 1,100 Italian volunteers. After crunching the numbers, researchers say they’ve found a gene that is correlated with increased coffee consumption. The subjects who had the gene on average drank one less cup of coffee every day than the subjects who did not have the gene.
Scientists theorize that the gene makes people metabolize caffeine more slowly, so they get a sustained caffeine boost from less coffee. People without the gene reportedly metabolize caffeine more quickly, so they go back and drink more coffee to make up for it.
After the Italian study, researchers conducted a similar experiment in the Netherlands and got the same results.