Coffee is one of the most widely consumed beverages in the world – in part for the stimulant effect of the caffeine. Researchers have recently begun questioning whether coffee drinking habits could be partly explained by genetic influences.
To investigate this question, over 1,200 people in Italy who had detailed genetic information available were asked about their daily coffee drinking habits.
People with a particular gene variant called PDSS2 drank one cup less a day on average compared to those people without the variation. The PDSS2 gene codes for an enzyme necessary for the production of coenzyme Q10, an important protein in mitochondria, which are important for energy production.
PDSS2 is also thought to play a role in the expression of genes involved in caffeine metabolism. So people with the PDSS2 gene variant have reduced capacity to metabolise caffeine. Slower caffeine metabolism means it stays in the body for longer, so less coffee is needed to get the same caffeine ‘hit’. At least that’s the hypothesis.
This research adds to previous work linking genetic influences on caffeine metabolism. A perceived need for coffee in order to being able to function as a human first thing in the morning could be a combination of both habit and potentially your genes.