I love a cup (or four cups) of coffee in the morning. I enjoy the taste, I enjoy the ritual of grinding beans, and, yes, I enjoy the kick I get from the caffeine. It's just a nice way to start the day. 

But, as with all nice things, coffee is sometimes misunderstood. This offends me—both as a coffee drinker and as a fan of science—so I thought I'd look into a few common coffee myths and dig up some actual science. 

Dark roast isn't stronger

Many people think that dark roasts are stronger, and have more caffeine, than light roasts. And this makes an intuitive sort of sense—dark roast has a stronger taste, so why wouldn't it also have more caffeine. It's not true, though. 

The difference between dark and light roast is, as the name implies, how much the coffee beans are roasted. A 2017 paper published in Nature by Megan Fuller and Niny Z. Rao of Thomas Jefferson University compared the caffeine concentration in coffee brewed using the same mass of medium and dark roasted coffee, all Arabica beans grown in the Kona Region of Hawaii. The results showed a "higher concentration in medium roast samples" than in dark.