Inter- and intra- generational transmission of obesity: Evaluating parent and child obesity in a new health behavior dataset

Introduction: Childhood obesity contributes to an elevated risk of later-life obesity and is associated comorbid conditions. While research has demonstrated a clear association between parent and offspring obesity, contributions of social context and sibling composition have not been well-specified. In this paper, we ask how different children within the same family may be affected by parental obesity with a detailed focus on the food environment. Methods: A 2011 web survey of Americans' health behaviors was conducted wherein adults were asked about their own food-related behaviors and their children's health. Data on adult BMI was available for 3663 adults with at least one child under 18 years old, and child obesity is calculated using z-scores. We fit a series of regression models in which the outcome of interest is child obesity status, with parent and sibling obesity as key independent variables. Models adjust for adult (age, frequency of fast-food meals, television/computer meals, stress eating, grocery store proximity, physical activity, subjective social status) and child characteristics (age, fast-food consumption, extra-curricular sports). Results: In households with one child, having an obese parent makes it more likely that the child will be obese (OR: 2.66, SE:0.33, p<0.001). In households with multiple children, having an obese elder sibling is comparatively more predictive of youngest-child obesity (2 children: OR:5.89, SE: 1.22, p<0.001; 3 children: OR:11.2, SE:4.88, p<0.001). Female child obesity is more strongly associated with parent obesity in all sibling configurations. Discussion: These findings suggest that considering offspring composition and elder sibling involvement in childhood obesity interventions may be constructive.