Americans drink a surprising amount of coffee—with somewhere in the neighborhood of about 64 percent of people drinking at least a cup a day and averaging out to about two to three cups of coffee per person. So it’s not so surprising that we’re also interested in knowing the health effects of coffee. The resulting constant flood of opinions can actually make things more confusing—such as coffee may help you live longer, but maybe not everyone, and maybe depending on what kind of coffee you drink. Overall, however, the general consensus seems to be that coffee has some sort of effect on our health. So how does that happen?
New preliminary research out of Erasmus University Medical Center in the Netherlands suggests that coffee may have an epigenetic effect on our bodies—meaning it doesn’t change our DNA, but it can change the way our genes express themselves. To use coffee as an analogy for these coffee findings, drinking a cup gives you a buzz that can change the way you act; in a similar fashion (but through different mechanisms), drinking coffee may also affect the way our genes act.
To reach their conclusion, the researchers conducted a meta-analysis of over 15,000 people across 15 different studies. “Collectively, this study indicates that coffee consumption is associated with differential DNA methylation levels,” the researchers write, “and that coffee-associated epigenetic variations may explain the mechanism of action of coffee consumption in conferring disease risk.”
Two important points, however: First, these findings are still preliminary and have not been fully peer reviewed. And second, understanding how coffee may affect our genes doesn’t necessarily imply that the effects are good or bad. For instance, knowing that caffeine is the ingredient in coffee that perks us up doesn’t imply that caffeine is good for us. Along those lines, the authors of the study conclude by writing, “Future studies [...] are warranted to validate our findings and to explore the biological relevance of the associated DNA methylation sites and genes in beneficial and harmful association with different health outcomes.”