I know how they say cotton kills, etc.. I have been wearing cotton long johns in the military, skiing, etc.. and they have kept me warm in some pretty cold conditions. I have had them soaking wet in the cold with sweating because of being overdressed while skiing one time. I never had felt cold, the edge of the sleeve actual turned into a chunk of ice,I crushed it up and everything was fine but those were when I stayed active and I never noticed how wet it was until I went in the lodge to get something to eat later on that night. If I had cut my layers down it would not have gotten that bad, but I was on a mountain skiing and no where to put the cloths. There is something to be said about the old cotton long johns, cheap, warm and my father and his father and so on have been wearing them for decades and they lived long lives. I've used them over 40 years and even in -25 below and I'm still here. But they are a pain to get the water out once wet, but with a good fire has helped.