We also measured leptin concentrations in these tree groups of subjects. In the city dwellers the powerful relationship between body mass index (BMI) and leptin concentrations was at a higher level of intercept of those in the villages meaning that at any levels of BMI leptin concentrations were around twice as high in town dwellers as villages. This may simply mean that BMI in a village farmers represents muscle mass rather than fat mass and that urbanization is associated with the much higher proportion of total body fat at any level of BMI.