Epidemiology and Risk Factors of Childhood Obesity

Childhood obesity affects millions worldwide and represents one of the most pressing public health challenges of the twenty-first century. Its epidemiology is characterised by marked disparities across geographic regions, socioeconomic strata and ethnic groups. While high-income countries continue to report stabilising yet elevated rates of childhood obesity, the most rapid increases are observed in low- and middle-income settings undergoing urbanisation and nutritional transition. Globally, the proportion of children with overweight or obesity has risen steadily over recent decades, driven by complex interactions between genetic predisposition and environmental influences. Risk factors are multifactorial and interrelated. Dietary factors such as excess consumption of energy-dense, nutrient-poor foods combine with reductions in physical activity and increases in sedentary behaviour to fuel positive energy balance. Social determinants including household income, parental education and neighbourhood infrastructure mediate access to healthy foods and opportunities for active play. Early-life exposures—from intrauterine nutrition to infant feeding practices—further programme long-term adiposity trajectories. Psychosocial stress, disrupted sleep patterns and marketing of unhealthy foods compound these effects. The consequences of childhood obesity extend beyond immediate health impacts to include elevated risk of type 2 diabetes, cardiovascular disease and psychosocial morbidity in adulthood. Mitigating this epidemic requires integrated strategies spanning policy, community interventions and clinical care, with attention to equity and sustainability.

Research from Nature Portfolio

A systematic review and meta-analysis conducted in 2024 has provided updated prevalence estimates of overweight and obesity among children in South Asian countries. By synthesising data from nearly half a million participants, this study revealed that approximately one in five young people in the region now present with overweight or obesity. Subgroup analyses identified marked heterogeneity between countries, with prevalence particularly high in urban settings. Temporal trends indicate a consistent upward trajectory over the past two decades. The findings highlight the need for region-specific surveillance and culturally tailored prevention programmes that address both undernutrition and overnutrition in transitional societies.

Epidemiology and Risk Factors of Childhood Obesity publication trend

The graph below shows the total number of articles in epidemiology and risk factors of childhood obesity across all publications each year (not limited to Nature Index journals).

Technical terms

Body Mass Index (BMI): A ratio of weight to height squared used to classify underweight, healthy weight, overweight and obesity.

Prevalence: The proportion of a population affected by a condition at a given time.

Meta-analysis: A statistical method that combines results from multiple studies to derive pooled estimates.

Sedentary behaviour: Low-energy activities such as sitting or screen time associated with minimal physical movement.

Metabolic syndrome: A cluster of conditions including raised blood pressure, dyslipidaemia and insulin resistance that increase cardiovascular risk.

References

1. Trends estimation of obesity prevalence among South Asian young population: a systematic review and meta-analysis. Scientific Reports (2024).
2. Is Childhood Overweight/Obesity Perceived as a Health Problem by Mothers of Preschool Aged Children in Bangladesh? A Community Level Cross-Sectional Study. International Journal of Environmental Research and Public Health (2019).
3. Association of Anthropometric Indices With Metabolic Phenotypes of Obesity in Children and Adolescents: The CASPIAN-V Study. Frontiers in Endocrinology (2019).
4. Cardiovascular Implications in Idiopathic and Syndromic Obesity in Childhood: An Update. Frontiers in Endocrinology (2020).