Intergenerational transmission of the Body Mass Index (BMI) in children and adolescents: a panel study for Mexico

Alma Sobrevilla, University of Glasgow

Child obesity in Mexico has reached alarming levels in the last few years. In this paper we use data from the Mexican Family Life Survey (MxFLS) to study the parental transmission of a measure usually employed in the identification of overweight and obesity: the Body Mass Index (BMI). We find a strong correlation between the BMI of fathers and children, which seems to hold even after controlling for genetic predispositions and time-invariant habits. This father-child relationship tends to be stronger for families with a high socioeconomic status and for households with a small number of members. Regarding the maternal transmission of BMI we find that it is strong and highly significant under an OLS approach, but it is not robust to the inclusion of household or individual fixed effects. Also, children of working mothers tend to experience a higher level of maternal transmission, with respect to children whose mothers do not work. In general, both parental transmission coefficients seem to increase with the child’s age, however the marginal effect of age is not constant across the age distribution. There is also slight evidence of a role modelling process in which children tend to experience a higher transmission from the parent of the same sex. Finally, we find that obese and overweight parents are more prone to transmit their anthropometric status relative to normal weight parents, which suggests the presence of an intergenerational reinforcement process enhancing obesity among children and adolescents.