The mechanisms by which financial strain affects health are not well understood. In this paper, we conduct a longitudinal mediation analysis of the Dutch National Bank Household Survey. To quantify the relative importance of biological and nonbiological pathways from financial strain to health, we consider smoking, heavy drinking and being overweight as plausible behavioural responses to financial strain but find that only 4.9% of the response of self-reported health to financial strain is mediated by these behaviours. Further analysis indicates that although financial strain increases impulsivity this has little effect on unhealthy behaviours. Economic stresses therefore appear to be distinct from other forms of stress in the relatively minor influence of nonbiological pathways to ill-health.