It seems that medieval English peasants were generally much healthier than most people today. Or at least their diets were generally better: lots of vegetables and some fruit, plus a fair amount of fish and meat when they could get it. Which, apparently was oftener than one might suppose. Of course they had to work pretty hard, and sometimes they went "short"(generally in July, just before harvest time), and nobody seemed to live terribly long. But they didn't get things like coronary disease --- probably in part because people in medieval times got lots of exercise of one kind and another.
I note all of this, because, as I have mentioned, my Great Science Fiction Masterpiece With Neandertals is set in medieval England. Furthermore, it's set in a particularly "healthy" period for most people, namely the so-called "medieval climatic optimum" which lasted from about 800 to 1300 CE. Oh, maybe that's a little generous for the length of time, but, interestingly, this time period more or less coincides with the so-called "Viking era", which, as the Gentle Reader might guess, was the time when people in various parts of Europe became familiar, one way or another, with the Scandinavian people. Which is also, in a way, an important background to my Great Science Fiction Masterpiece With Neandertals. But if the Vikings invaded England, and formed the so-called Danelaw, at least the people already there were a healthy lot.