In the last few decades, the prevalence of obesity has expanded rapidly and now constitutes a grave public health concern across the developed world. Obesity is negatively associated with, among other factors, education and healthcare quality, which are factors that governments can and do influence through welfare policies. This study investigated to what extent the change in the prevalence of obesity is lower in more generous welfare states. Based on pooled time series cross‐section regressions for 15 developed countries over 25 years, we found that the more generous are transfer payments, health policy and education policy, the lower is the increase of obesity prevalence. These findings have important implications for public policy formation and the public health and welfare state literatures.