@jackiem95 The amount of reduced caffeine is very little according to most studies. I do know my heart does not beat as fast with a dark roast as it does with a decaf. So I think it at least puts it in category of decaf... all decaf still has caffeine. I also know I have personally have less acid production with a darker roast. Most studies say about acid: Dark Roasts – a study published in 2010 found that dark roast coffee is easier on the stomach than light roasts because it produces an ingredient that prevents hydrochloric acid from building up in the stomach. I mostly go by what my body tells me and not studies .. everyone is different 😀

@jackiem95 @fourof5zs I was told by a person who runs a coffee roastery that the dark roast has less acid because in the longer roasting process more of the acid is burned off. I never heard that there was a difference in caffeine, that's interesting. I wonder how cold brew compares. I use a Keurig and there are now cold brew cups with liquid in them that you can use in the machine. The resulting coffee is so smooth, it's really delicious. I find I don't need any creamer in it, whereas that is usually a must for me.
JK