Research: genes determine people's coffee needs vary from country to country

Why are some people able to drink several cups of coffee a day while others can't stand one? A study published recently in the British journal Scientific Reports shows that genes determine people's demand for coffee.

Researchers from the University of Edinburgh and colleagues in Italy and the Netherlands first investigated Italian genes and coffee drinking, with 370 people from one village in southern Italy and 843 from six villages in northeastern Italy.

The results showed that coffee consumption was associated with a gene called PDSS2. People with the DNA variant drank about one cup less coffee a day on average than others.

The researchers then looked at the genes and coffee consumption of 1731 Dutch people and found similar results.

The report also said that because Italians and Dutch coffee drinking habits are different, the degree of genetic influence on coffee consumption in the two countries is slightly different.

The researchers analyzed that changes in this particular gene may inhibit the ability of cells to break down caffeine, causing caffeine to stay in the body longer. People with the variant have a lower tolerance to caffeine and drink less coffee