'Globesization': ecological evidence on the relationship between fast food outlets and obesity among 26 advanced economies

The aim of this study was to investigate the relationship between the density of fast food restaurants and the prevalence of obesity by gender across affluent nations. Data on Subway’s restaurants per 100,000 people and proportions of men and women aged 15 years or older with a body mass index (BMI) higher or equal than 30 Kg/m2 were obtained for 26 of 34 advanced economies. Countries with the highest density of Subway restaurants such as the US (7.52 per 100,000) and Canada (7.43 per 100,000) tend also to have a higher prevalence of obesity in both men (31.3% and 23.2% respectively) and women (33.2% and 22.9% respectively). On the other hand, countries with a relatively low density of Subway restaurants such as Japan (0.13 per 100,000) and Norway (0.19 per 100,000) had a lower prevalence of obesity in both men (2.9% and 6.4% respectively) and women (3.3% and 5.9% respectively). Unadjusted linear regression models showed a significant correlation between the density of Subway’s outlets and the prevalence of adult obesity (β=.46; p=0.02 in men and β=.48; p=0.013 in women). When the data were weighted by population size, the association became substantially stronger in both men and women (β=.85; p=0.0001 and β=.84; p=0.0001, respectively). Covariate adjustment did not reduce the size of the associations. Our study raises serious concerns about that the diffusion of fast food outlets worldwide and calls for coordinated political actions to address what we term ‘globesization’, the ongoing globalization of the obesity epidemic