The association of excessive growth with development of general and central obesity at 7 years of age in every period after birth in Chilean children

• Among Chilean children, most new cases of obesity/overweight occur in infancy.
• Overweight after infancy increases risk of obesity (general and central) at 7 y.
• There is tracking of overweight and obesity after birth.
• There is no evidence of critical periods in early life for developing obesity at 7 y.

ObjectiveTo determine whether overweight or obesity between 0 and 6 y increases the probability of developing general/central obesity at 7 y.MethodsWeight, height, and waist circumference were assessed between 0 and 6 y in 628 Chilean children. Body mass index, incidence of overweight (IOW), incidence of obesity (IOB), and prevalence at birth and 0 to 6, 6 to 24, 24 to 48, and 48 to 72 mo and odds ratio (OR) and 95% confidence interval (95% CI) for developing obesity/central obesity at 84 mo were calculated by sex.ResultsIOW was highest at 6 to 24 mo (20.3% and 21.1% for girls and boys, respectively); IOB was highest at 6 to 24 and 24 to 48 mo (11% and 10%, respectively). OR for developing obesity at 7 y was significant if overweight was present 24 to 48 mo in girls and 6 to 24 mo in boys OR 2.47 [95% CI, 1.5–4] and OR 2.26 [95% CI, 1.30–3.92], respectively, and much higher for children who were obese, OR 6.1 (95% CI, 3.03–12.21) for girls 6 to 24 mo and OR 6.57 (95% CI, 2.55–16.86) for boys 0 to 6 mo. IOW or IOB was not associated with obesity at 84 mo, except for the previous period. Overweight also increased the risk of central obesity very early on, after 6 mo in girls and after birth in boys OR 3.8 [95% CI, 2.3–6.2] and OR 2.5 [95% CI, 2.04–3] at 6 to 24 and 0 to 6 mo, respectively, whereas obesity in all periods was associated with a significantly higher OR of presenting central obesity at 7 y.ConclusionThere is tracking not only of obesity but also of overweight after birth for developing general or central obesity at 7 y. Prevention should begin very early on.