Coffee is one of the most widely consumed―and socially acceptable―stimulants in the world. For many of us, not a day goes by without consuming one or several cups of java. So, understanding its long-term effects on health is important. Previously, a number of studies have suggested that coffee consumption may reduce the risk of cardiovascular disease (CVD). More recently, a team of researchers set out to validate these findings. Specifically, they wanted to see if the health-protective benefits might not be related to genetics, instead: the presence of the CYP1A2 gene, which codes for an enzyme involved in caffeine metabolism.
In this prospective cohort study, researchers examined the genetic data and daily coffee consumption of 347,077 individuals aged 37-73 years over a 4-year period. They found that, compared with light coffee drinkers (1-2 cups/day), adults who did not consume coffee, consumed decaffeinated coffee, or consumed more than 6 cups/day had an increased risk of CVD (11%, 7%, and 22% respectively). Luckily, for coffee lovers, the authors observed no change in CVD risk based on genotype, suggesting that the health benefits of coffee consumption are NOT affected by an individual’s ability to metabolize caffeine. Phew!
As evidenced by the above study, the benefits of coffee consumption occur along a U-shaped curve, with those on either far-side of the curve (people who do not drink coffee/only drink decaf and people who drink >6 cups/day) missing out on the cardio-protective benefits that caffeinated coffee provides and increasing their risk of CVD in the process. People in the middle (between 1-5 cups/day) of the curve appear to reap some benefits.
How much coffee exactly is ideal? That’s where things become a bit more challenging. These studies are performed in a lot of different countries, where cups are brewed at different strengths and in different sizes. Additionally, some of the data they collect is controlled while other data is self-reported. So, while we certainly can’t draw any definitive conclusions, after a lot of reading/cross-checking/puzzling, here is where we came out: if your objective is to maximize the health benefits of coffee, moderate consumption of 1-2 cups (8-16 fl oz) feels like a good bet. But on those especially tough days, an extra cup probably won’t do too much harm.
Go Deeper: Learn more about the other health benefits and risks of coffee we discovered on our quest here.