Large, unpredictable and not fully insurable health-care costs represent a source of background risk that might deter households’ financial risk taking. Using panel data from the Health and Retirement Study, we test whether universal health insurance, like Medicare for over-65 Americans, shields against this risk promoting stockholding. We adopt a fixed-effects estimation strategy, thereby taking into account household-level heterogeneity in health status and private insurance coverage. We find that, before Medicare eligibility, households in poor health, who face a higher risk of medical expenses, are less likely to hold stocks than their healthier counterparts. Yet, this gap is mostly eliminated by Medicare. Notably, the offsetting is primarily experienced by households in poor health and without private health insurance over the observation period.

Health risk is increasingly viewed as an important form of background risk that affects household portfolio decisions. However, its role might be mediated by the presence of a protective full-coverage national health service that could reduce households’ probability of incurring current and future out-of-pocket medical expenditures. We use SHARE data to study the influence of current health status and future health risk on the decision to hold risky assets, across ten European countries with different health systems, each offering a different degree of protection against out-of-pocket medical expenditures. We find robust empirical evidence that perceived health status matters more than objective health status and, consistent with the theory of background risk, health risk affects portfolio choices only in countries with less protective health care systems. Furthermore, portfolio decisions consistent with background risk models are observed only with respect to middle-aged and highly-educated investors.