Experts at the International Congress on Obesity in Mexico City reveal that childhood obesity results from a complex interplay of genetic, environmental, and socioeconomic factors, with implications for earlier detection and broader interventions.
Experts at the International Congress on Obesity in Mexico City said childhood obesity is rarely the result of one factor alone, pointing instead to an overlap of genetics, family history, pregnancy-related influences, socioeconomic conditions and the built environment. Antje Körner, a paediatrician and professor of metabolic research at the University of Leipzig, said the condition develops through biological inheritance, epigenetic effects and the surroundings children encounter early in life, and that these pressures can build over time into insulin resistance, hypertension and cardiovascular disease at younger ages. She argued that care should involve more than paediatrics alone, with cardiology and other specialties contributing to earlier detection and treatment.
Körner also said research is broadening understanding of the genetic drivers of severe obesity. Her group has studied ectopic expression of the ASIP gene in adipose tissue, a finding that emerged after standard genetic tests failed to explain severe obesity in a 12-year-old girl. According to the work, ASIP can interfere with the melanocortin 4 receptor, a pathway central to appetite and energy balance. The research was later replicated in a much larger cohort, identifying a small number of carriers and helping to show that obesity diagnostics may need to look beyond single-letter DNA changes to larger chromosomal alterations.
Evidence presented at the meeting also reinforced the role of parental weight, especially maternal obesity, as a major predictor of childhood obesity. Körner said that risk is not explained only by household eating habits, because metabolic and epigenetic effects can be passed on before birth. Research cited in the related material shows that parental obesity raises familial risk and that a portion of childhood obesity is linked to inherited gene defects. Birth weight and fetal growth also matter, with studies suggesting that excess growth in the womb can raise the odds of later obesity. A Mexican analysis presented at the congress estimated that large-for-gestational-age births and macrosomia could account for about 4% of future childhood obesity cases and 5% of adult obesity cases in the country.
The meeting also turned attention to the food environment. Körner said deprivation often brings greater exposure to fast food, while better-resourced neighbourhoods tend to offer more varied diets. She added that urban design matters too, because limited green space can push children indoors and increase screen time. In Mexico, Alejandra Contreras Manzano of the National Institute of Public Health said stronger controls on ultraprocessed food sales could help, and her team is assessing how schools are applying rules on food and warning labels. Mexico’s national survey data show obesity remains common among schoolchildren and adolescents, underlining the scale of the challenge and the limits of approaches focused only on individual behaviour.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
