Since the 1950s, life expectancy in Europe and the United States has improved at a steady pace, driven mostly by gains at older ages. However, these lives are punctuated by more chronic disease than ever before, contributing to substantial morbidity and disability. Using the Future Elderly Model, we simulate longevity and disability over the remaining lifetime for cohorts of older Europeans and Americans. The model simulates total longevity and disability over the course of a lifetime for representative cohorts of older Europeans and Americans. We then consider two counterfactual scenarios. In the first, we reduce the presence of the chronic illness at age 50, if present (i.e., the impact of removing stock). In the second, we reduce the incidence of chronic disease after age 50, among those developing disease after this age (i.e., the impact of removing flow). We then assess the impact on the treated and the average effect on the overall cohort, in terms of life-years (LYs) and disability-free life-years (DFLYs). We study Europe and the US to understand how differences in older age prevalence and incidence between the two regions influence the burden of disease, as well as the trade-offs between treatment and prevention by disease. We see that investment in both treatment and prevention for cancer, diabetes, and heart disease show tremendous promise for breaking Europe and the United States out of the expensive equilibrium we now find ourselves in as a result of demographic gains.