The continuous aging of the EU population poses important challenges to the sustainability of welfare states. Part of the solution is to ensure that people not only live longer but also better (i.e., can function independently while remaining free of disease and disability), which may be achieved through better nutrition. In order to test that proposition, we develop a behavioural model of diet quality choice and health determination. The simultaneous equation model, which accounts for the endogeneity of dietary and other lifestyle choices, is applied to a sample of older people from Italy and allows for the possibility of bi-directional causality between diet and health.