Efficiency analyses have been widely used in the literature to rank countries regarding their health system performance. However, little place has been given to the environmental aspect in that literature. Therefore, two countries with the same characteristics could experience completely different healthcare system outcomes just because they do not have the same level of pollution, which is a major determinant of inhabitants' health. This paper analyses the effect of the environmental quality on the OECD countries' health system outcome, measured by the life expectancy at birth. Using a stochastic frontier model, we show that the longevity league table of OECD countries changes significantly whether the environmental index is taken into account or not. This, once again, underlines the critical importance of the environment when addressing health issues.