The double burden of overweight or obesity and anemia among women married as children in India: A case of the Simpson's paradox

Background: Child marriage, defined as marriage before age 18 years, could impact women's nutritional status through biological as well as environmental and socioeconomic attributes affecting diet and lifestyle behaviors. This study aims to examine whether women married as children have a differential risk of individual level double burden of overweight/obesity and anemia at adult age compared to women married as adults. Methods: Using nationally representative data from India we estimated multinomial logistic regressions to obtain relative risk ratios (RRR) in favor of mutually exclusive anemia and overweight/ obesity conditions among women aged 20–49 years. We estimated the model for full sample and for sub-samples by household wealth groups. Results: We find that women who were married as children had a lower relative risk (RRR=0.941) of the double burden of anemia and overweight/obesity in the full sample. However, when sociodemographic correlates were accounted for and assessed in sub-groups by wealth groups, they had a higher relative risk (ARRR ranging from 1.079 to 1.204) of the double burden compared to women married as adults. Conclusion: Our results thus portray a classic case of the Simpson's paradox by documenting a reversal of association between child marriage and occurrence of the double burden of malnutrition in the subgroup level than that in the general population. This finding provides a critical policy insight for effective public health interventions to improve women's health and wellbeing, particularly in low resource settings.