Obesity and the built environment: the case of Tehran

Abstract

Due to the high rates of obesity in Iran, this study aimed to investigate the relationship between density, accessibility to public transport and green spaces, obesity, and related diseases in Babol. Data were collected from 1200 participants, and logistic regression was employed to analyse health indicators such as body mass index (BMI), blood pressure, and diabetes, alongside environmental indicators including population density, residential density, accessibility to bus and taxi stations, the number of stations, and green space area. The study found that living in areas with a density of over 120 people per square kilometre reduces the likelihood of being overweight or obese compared with areas with a density of 100 to 120 people. Access to green spaces within a 200-metre radius did not show a significant association with diseases. There was a weak negative relationship between the number of public transportation stations at different distances and BMI, indicating lower levels of overweight and obesity. Changing from neighbourhoods with lower residential densities to higher residential densities reduced the likelihood of developing heart disease and diabetes by about 74% and 44.4%, respectively. The presence of green spaces in neighbourhoods had a weak correlation with the reduction of obesity and related diseases. Increasing the number of taxi and bus stations from one to three within a 400-metre radius significantly reduced the likelihood of developing high blood pressure by approximately 70% and diabetes by 56.5% within a 200-metre radius. Living within a distance of less than 150 metres from the nearest public transportation station or nodal points was associated with a 51.3% lower probability of developing high blood pressure compared with living within a distance of 300 to 500 metres from public transportation stations. Based on the findings, the paper presents possible implications for policy and practice.