1) People who say they don't stress 2) People who say they stress but don't believe it's harmful 3) People who say they stress and believe it's harmful
I find the (3) group is the one actually stressing, feeling all the anxiety etc.
The (2) group just talks about feeling stressed, but they just mean that they had lots of responsibilities etc, they didn't suffer actual stress (the mental issues associated with it) like the (3) group.