BACKGROUND: Malnutrition is a risk factor for childhood development disorders. Although undernutrition is recognized as a public health problem, the impact of overweight/obesity on childhood development remains unknown. The objective is to determine the effects of undernutrition, overweight, and obesity on development in children aged between 1 and 59 months in rural/urban areas of Mexico. METHODS: The Childhood Development Evaluation (EDI, for its acronym in Spanish) test was administered to children 1-59 months of age who visited primary care units in Guanajuato State, Mexico, between 2013 and 2015. The World Health Organization classification (weight/height ratio) was used for nutritional status. Logistic regression adjusted by sex, age, rural/urban, and level of marginalization, used to calculate odds ratios (OR) to stablish the association between nutritional status and developmental outcomes. RESULTS: 34,972 participants were included. 50.3% were male, 39.5% had a very low level of marginalization, 58.6% lived in urban areas, and 55.0% were beneficiaries of a conditional cash transfer program. Age distribution: 31.9% between 1 and 12 months old
17.5% between 13 and 24 months old
16.3% between 25 and 36 months old
and 34.3% between 37 and 59 months old. Overall 85.8% of participants had normal nutritional status, whereas 9.1% were identified as malnourished, and 5.0% were classified as overweight or obese. 79.1% had typical development. The OR for atypical development was 1.820 (95% confidence interval [95% CI], 1.671-1.981) for mild undernutrition
2.796 (95% CI: 2.195-3.562) for moderate undernutrition
14.903 (95% CI: 8.149-27.257) for severe undernutrition
and 1.160 (95% CI: 1.030-1.307) for overweight/obesity. CONCLUSION: Undernutrition and overweight/obesity are factors that increase the risk of developmental problems in children <
5 years of age.