Using a panel dataset of 70 countries spanning 42 years (1970-2011), we investigate the distinct effects of economic and social globalisation on national trends in markers of diet quality (supplies of animal protein, free fat and sugar, prevalence of diabetes, average body mass index). Our key methodological contribution is the application of the grouped fixed-effects estimator, which extends linear fixed-effects models to include both time-invariant and time-varying unobserved heterogeneity, under the assumption that both the latter and the former follow group-specific patterns. We find that increasing social globalization has a significant impact on the supplies of animal protein and sugar available for human consumption. Specific components of social globalisation like personal contacts with foreigners and above all information flows drive these results. Economic globalisation has no effect on dietary outcomes, and has a negative impact on health. These findings suggest that the social and cultural aspects of globalisation should deserve greater attention in studies of the nutrition transition.