For most of us, drinking a cup of coffee is about getting that jolt of caffeine. But are you drinking the right roast to maximize your buzz consumption? Chances are, probably.
There's a common misconception that dark roast has more caffeine than light roast because it's darker. Other folks believe that light roast has more caffeine than dark roast because caffeine is lost when beans are roasted. Both of those schools of thought are wrong because all roasts of the same bean have basically the same amount of caffeine. Caffeine is actually extremely stable during the roasting process. The effect of roasting on caffeine is so minimal it can really only be observed in a controlled laboratory setting.
Light roast, dark roast, medium roast, it will all pretty much get you equally caffeinated. Unless, that is, you're drinking different species.
There are two main coffee species that are cultivated in the world: Arabica and Robusta. Arabica is more expensive and tastier. Robusta is harsher and cheaper. But Robusta generally has more caffeine. An average morning cup of Robusta coffee (about 12 oz.) could contain anywhere between 232 to 800 milligrams. And an average cup of Arabica would contain somewhere between 84 and 580 milligrams -- that's about half the caffeine content of Robusta. The higher caffeine content actually makes Robusta less pleasant to drink.
So our takeaway is: pick the roast based on your taste preference -- light roast has a brighter flavor and is more acidic, dark roast is smoother -- and don't try to judge its caffeine content from its roast.