Peer-reviewed article
Patterns of Growth in Childhood in Relation to Adult Schooling Attainment and Intelligence Quotient in 6 Birth Cohorts in Low- and Middle-Income Countries: Evidence from the Consortium of Health-Oriented Research in Transitioning Societies (COHORTS)
Natalia Elvira Poveda, Fernando Pires Hartwig, Cesar Gomes Victora, Linda S. Adair, Fernando C. Barros et al. ·
Summary
Written by AI, not yet AICS's view · claude-haiku-4-5-20251001This study analyzed data from nearly 10,000 children across six birth cohorts in Brazil, Guatemala, India, the Philippines, and South Africa to understand how childhood growth relates to adult outcomes. Researchers measured children's height and weight at birth, age 2, mid-childhood, and adulthood, then examined links to adult schooling attainment and intelligence quotient (IQ). The key finding is that linear growth (height) in the first 1000 days of life strongly predicts both educational achievement and IQ in adulthood, but growth in later childhood does not have this association.
Key points
- Weight and length at birth were positively associated with both adult schooling attainment and IQ
- Linear growth from birth to age 2 showed the strongest associations with schooling attainment and adult IQ
- Growth (linear and relative weight changes) after age 2 through mid-childhood and into adulthood was not associated with schooling attainment or IQ
- Changes in relative weight across the entire life course were not associated with either schooling or IQ outcomes
- Findings were consistent across 5 low- and middle-income countries
Limitations
This is an observational study that establishes associations but cannot prove causation; other factors not measured in this analysis (such as socioeconomic status, parental education, or early childhood stimulation) may explain both growth patterns and adult outcomes.
Abstract
Background: Growth faltering has been associated with poor intellectual performance.The relative strengths of associations between growth in early and in later childhood remain underexplored.Objectives: We examined the association between growth in childhood and adult human capital in 5 low-and middleincome countries (LMICs). Methods:We analyzed data from 9503 participants in 6 prospective birth cohorts from 5 LMICs (Brazil, Guatemala, India, the Philippines, and South Africa).We used linear and quasi-Poisson regression models to assess the associations between measures of height and relative weight at 4 age intervals [birth, age ∼2 y, midchildhood (MC), adulthood] and 2 dimensions of adult human capital [schooling attainment and Intelligence Quotient (IQ)].Results: Meta-analysis of site-and sex-specific estimates showed statistically significant associations between size at birth and height at ∼2 y and the 2 outcomes (P < 0.001).Weight and length at birth and linear growth from birth to ∼2 y of age (1 z-score difference) were positively associated with schooling attainment (β: 0.13; 95% CI: 0.08, 0.19, β: 0.17; 95% CI: 0.07, 0.32, and β: 0.25, 95% CI: 0.10, 0.40, respectively) and adult IQ (β: 0.74, 95% CI: 0.35, 1.14, β: 0.73, 95% CI: 0.35, 1.10, and β: 1.52, 95% CI: 0.96, 2.08, respectively).Linear growth from age 2 y to MC and from MC to adulthood was not associated with higher school attainment or IQ.Change in relative weight in early childhood, MC, and adulthood was not associated with either outcome.Conclusions: Linear growth in the first 1000 d is a predictor of schooling attainment and IQ in adulthood in LMICs.Linear growth in later periods was not associated with either of these outcomes.Changes in relative weight across the life course were not associated with schooling and IQ in adulthood.