Identifying Early Metabolic Risks of Obesity in Mexican Children and Adolescents from a Semi-Rural Community in Mexico: Beyond BMI and into Biochemical and Nutritional Markers

<b>Background:</b> Childhood and adolescent obesity often coexist with micronutrient deficiencies and metabolic alterations, particularly in marginalized communities. <b>Objectives:</b> This cross-sectional study evaluated the biochemical, anthropometric, and dietary characteristics of 55 children and adolescents (ages 4-13) from Tlaltizapán, Mexico, to identify the early metabolic risk factors associated with excess weight. <b>Methods:</b> Nutritional intake was assessed through six-day dietary recalls and analyzed for adequacy against the national reference values. Anthropometric and biochemical indicators-including the BMI-for-age Z-score, waist-to-height ratio (WHtR), lipid profile, and plasma amino acid levels-were stratified by age and weight status. <b>Results:</b> Overall, 36.4% of participants were overweight or obese. Alarmingly, 89.4% of children and 94.1% of adolescents had low HDL levels, regardless of their BMIs. Several participants with a normal BMI showed elevated WHtR, triceps skinfold, and plasma branched-chain amino acids, suggesting hidden metabolic risks. The dietary analysis revealed an excess intake of sugars, proteins, and fats, alongside insufficient fiber, vitamins, and minerals. The adolescents had poorer adherence to dietary recommendations than children. <b>Conclusions:</b> These findings underscore the limitations of BMI alone and support the use of WHtR, skinfolds, and biochemical markers to detect preclinical obesity. Urgent, targeted nutritional strategies are needed in semi-rural areas to address the double burden of obesity and undernutrition.