Incredible but true, this is today's comment on a Kevin Drum post.
I have a problem with the argument that cortisol levels show that low social status is correlated with high stress, with the argument not the conclusion. How did levels of cortisol become the best measure of stress ? In the first place, there has to be some independent measurement of stress which lead to the conclusion that stress causes high cortisol levels. So we know cortisol levels are correlated with stress.