If you are one of those people who absolutely has to have your morning cup of coffee, there’s a good chance your genes are to blame.
Scientists have discovered people who have two versions of the genes CYP1A2 and AHR are much more likely to crave caffeine, The Daily Mail reported.
Those people are able to break down caffeine faster; therefore they can tolerate it better.
“It’s really an incredible story,” said Dr. Neil Caporaso, the study’s senior author of the National Cancer Institute. “People don’t suspect, but genetics plays a big role in a lot of behaviors, such as smoking and alcohol consumption. And now it turns out that it has a big part in how much caffeine we drink.”
Researchers from the Harvard School of Public Health looked at the genes of more than 47,000 middle-aged adults in the U.S. who were asked questions about their caffeine intake (coffee, tea, soda and chocolate).
The people with those specific genes tended to drink an average of 40 milligrams more caffeine a day, which equals a can of soda or a third of a cup of coffee, compared to those who did not have versions of those genes.