Five studies involving 47,341 U.S. participants of European descent have spotted a mutation in your genetic makeup that may determine whether or not you want that extra cup of coffee during the day.
The genes in question are known as CYP1A2, which is involved with the body’s caffeine metabolism, and AHR, which regulates CYP1A2. Scientists found that people with high-consumption variants of either gene on both chromosomes consumed on average about 40 mg more caffeine per day than people who didn’t have the mutation on either chromosome.
Forty milligrams is not a huge amount, equivalent to a can of soda or a third of a cup of coffee. The researchers measured all sources from which participants got caffeine, including soda, tea and chocolate, but about 80% came from coffee.
The authors acknowledge that the influence of these genes on caffeine intake is small, accounting for less than 1% of the variation in coffee consumption in the reviewed studies. But the results suggest that there may be many other genes that contribute to how much caffeine people consume, and may help researchers better understand the effects of the drug on the body.