A raft of studies are pointing to the worrying effects of poverty on worse physical and mental health. A new American study showed that being unemployed, even for a short period of time, increases the risk of heart attacks, and that having multiple job losses massively ups that risk. . This was a big study, of over 13,000 Americans between 50 and 70 over nearly a decade. The risk of acute myocardial infarction after job losses were very high, as great as seen in smoking, high blood pressure and type 2 diabetes.
These processes seem to start very early. Rather frighteningly, a new study has even found that child poverty as well as stress as an adult, and living in poor neighbourhoods, can all have an effect on one’s gene expression, particularly in relation future immune responses. . This study showed that people who had experienced childhood poverty had different gene methylation from those who hadn't, despite the fact everyone in the cohort had achieved the same socioeconomic status later in life. Early poverty left a detectable and lasting molecular mark on an individual's DNA.
The ways in which these processes become enacted throughout the lifespan are complex and subtle. Another new study by Amedeo D'Angiulli of Carleton University in Ottawa, Canada  showed that children from lower socio-economic circumstances are less able to screen out stimuli than those from better economic circumstances. Their very brain waves are different, for examples poorer children having higher theta waves. They also had higher cortisol levels, maybe less surprisingly. It is likely that living in poorer environments leads one to be more vigilant, relying more on basic survival mechanisms. and so be less able to relax and concentrate than more privileged children. This in turn as we know will have an effect on immune functioning. Indeed rather shockingly by only about 6 months we have learnt that infants from lower socio-economic circumstances are less able to concentrate and are more stressed, on average , both in free play and in attentional tasks. The effects of poverty and deprivation start very young and last a lifetime, indeed they affect how long a lifetime is.
 Gallo WT, ‘Evolution of research on the effect of unemployment on acute myocardial infarction risk: Comment on “the cumulative effect of unemployment on risks for acute myocardial infarction”’, Arch Intern Med, pp. 1–2, Nov. 2012.
 L. L. Lam, E. Emberly, H. B. Fraser, S. M. Neumann, E. Chen, G. E. Miller, and M. S. Kobor, ‘Factors underlying variable DNA methylation in a human community cohort’, Proceedings of the National Academy of Sciences, vol. 109, no. Supplement 2, pp. 17253–17260, 2012.
 A. D’angiulli, P. M. Van Roon, J. Weinberg, T. F. Oberlander, R. E. Grunau, C. Hertzman, and S. Maggi, ‘Frontal EEG/ERP correlates of attentional processes, cortisol and motivational states in adolescents from lower and higher socioeconomic status’, Frontiers in Human Neuroscience, vol. 6, 2012.
 M. W. Clearfield and K. E. Jedd, ‘The Effects of Socio‐Economic Status on Infant Attention’, Infant and Child Development, 2012.