A series of three studies involving Australian and Irish university students found that sleep characteristics mediate the relationship between social class and both physical and mental health. The results suggest that students from higher social class backgrounds may, in part, have better health due to superior sleep patterns compared to their peers from lower class backgrounds. The study was published in the British Journal of Psychology. ...
Maybe I missed something, but I did not see that this was about poverty specifically. I suspect something like this runs across the spectrum not just poverty though of course it is probably worse in that case. For example in organizations, it is fairly well know that the over achievers can suppress the performance of people around them. This too has to be stressful.
3-year-old children don’t work in organisations. This research is on babies and very small children, who are still undergoing brain development.
Poverty is far from the only stressful thing in the world, I agree.