Obesity has become a global health crisis, affecting people of all ages, regions, and socio-economic backgrounds. While individual behaviour and genetic factors contribute to obesity, the role of economic complexity in the evolution of obesity rates has not yet been empirically studied. Using a large panel of 110 countries over the period 1976-2015, this article estimates the linear and non-linear links between obesity and economic complexity. According to baseline results, an improvement in economic complexity will lead to an increase in obesity up to a certain threshold. Beyond this turning point, any further increase in economic complexity will significantly contribute to obesity reduction. The issue of simultaneity is tackled using the two-stage instrumental variable method. Our findings support the Obesity Kuznets Curve (OKC) pattern, which suggests that economic progress and obesity have an inverted U-shaped relationship. Our results suggest that greater embeddedness of knowledge in the products produced and exported by a country increases the likelihood of obesity in society, at least up to a threshold. From these results, some important policy implications are discussed.