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Urbanization is considered one of the key drivers of the global rise in obesity [68]. The percentage of a country’s population living in urban areas is one of the strongest positive correlates of BMI among both women and men [57,58,69]. Living in urban areas is associated with a greater probability of being overweight, even after controlling for education, but the association between urban residence and overweight is weaker in countries with higher per capita GDP levels [59]. For example, a study in Peru has shown that urban residents and rural‐to‐urban migrants have a higher level of obesity than the rural population [70]. These differences are mostly associated with transportation, food access, open spaces, mass media, and sedentary jobs (mostly associated with mechanization), resulting in less physical activity, more sedentary time, and overall higher levels of overweight and obesity.

Within urban areas, it is increasingly evident that there is a difference in obesity levels between low‐ and high‐income neighborhoods, with residents of the former showing higher levels of obesity [71]. One of the underlying drivers of this disparity is the food environment. Areas can be classified as “food deserts,” defined as a lack of access to affordable, nutritious foods, or “food swamps,” defined as areas with a high density of fast‐food restaurants and junk food [72]. In both food deserts and food swamps, residents are at greater risk of obesity due to unhealthy diets. A recent review has shown a positive association between access to green spaces and physical activity and a negative association between access to green space and screen time, BMI, and weight among children [73].

Nonetheless, a recent global study has shown that more than 55% of the global increase in the average BMI observed over the past three decades is due to an increase in BMI in rural areas [74]. This disparity is due to a faster increase in BMI in rural areas when compared to urban areas in low‐ and middle‐income countries. As a consequence of current trends, the urban–rural gap is closing, especially for women, and in high‐income countries, the mean BMI is higher in rural areas.

Several studies have also explored spatial patterning of obesity within a given country. For example, in the United States, adults living in medium or small metropolitan areas have a higher prevalence of obesity compared to those living in large metropolitan areas, even after adjustment for age, race and Hispanic origin, education level, and smoking status [75]. Women living in non‐metropolitan areas also had a higher prevalence of obesity compared to women living in large metropolitan areas, even after adjustment for the aforementioned factors [75]. A comparative urban–rural analysis in the prevalence of central obesity in China showed that in 2011, both central and general obesity in rural adults exceeded that in urban adults [76].