Changing food patterns in developing countries: Income is related to Body Mass Index (BMI) and nutritional status among the urban and rural population of Dhaka, Bangladesh

Background: The emerging co-existence of underweight and overweight is one of the major international public health concerns. In developing countries traditional dietary patterns are increasingly replaced by western food patterns. Rapid urbanization and the increasing numbers of megacities influence the poverty structure as well as the distribution and accessibility of food. The objective of this study is to show the interdependence between raised income and improved dietary patterns and nutritional intake in Dhaka. Method: Baseline data from a prospective cohort study, conducted in Dhaka and adjacent rural areas in March 2008 was used. The sample size comprised 1,062 men and women aged 15–90 years. Bivariate, cluster, linear and multinomial logistic regression analyses were performed. To estimate associations of income and nutritional condition, the Body-Mass-Index (BMI) was applied as a proxy factor. Results: On average study participants spent 60% of their monthly individual income on food. 70% of the respondents had a normal BMI, 21% and 9% were underweight and (pre-)obese. Linear regression proved a positive association between income and BMI (regression coefficient 0.044; p<0.001). Men had a 1.5 (95% CI 0.92–0.98) higher chance of being underweight compared to women. Education was positively associated with obesity (school OR 1.99; 95% CI 1.08–3.64, university OR 8.31; 95% CI 2.85–24.26). Obesity was associated with having an own kitchen and being younger than 45 years; while sharing a communal kitchen and being older than 45 years were significantly associated with underweight. Discussion: In our study income is positively associated with BMI, so raising the income might contribute to the improvement in nutritional condition. In contradiction to literature, men are more likely to be underweight compared to women, which might be explained by differences in labor. Nutrition next to hygiene is an important health determinant in developing countries therefore further long-term research on dietary patterns is needed.