Association of early childhood lifestyle patterns with overweight in preschoolers and timing of adiposity rebound

BACKGROUND: An unhealthy diet, excessive screen time, low levels of physical activity and suboptimal sleep are known risk factors for childhood overweight and obesity (OW/OB). These energy balance-related behaviors tend to co-occur and combine into "lifestyle patterns" (LPs) that may have a synergistic effect on OW/OB. However, few studies have examined these LPs before preschool age, and none investigated the possible involvement of parental feeding practices (e.g., breastfeeding and timing of complementary feeding), non-screen leisure activities and sleep quality. We aimed to identify such LPs during the first 2 years of life and assess their associations with OW/OB at age 5 years and age at adiposity rebound (AR). METHODS: Participants were children from the French nationwide ELFE (Etude Longitudinale Française depuis l'Enfance) birth cohort. We used principal component analysis of 18 items characterizing parental feeding practices and children's energy balance-related behaviors (n = 13,121) to derive LPs. We analyzed the associations of LPs with OW/OB at age 5 years (International Obesity Task Force definition; n = 8,388) and age at AR (in days; n = 7,845) using multivariable logistic and linear regression models, respectively. RESULTS: We identified three LPs: "Early complementary feeding, discretionary consumption, high screen time", "Balanced diet, non-screen leisure activities", and "Healthy feeding practices, low dairy consumption, suboptimal sleep" patterns. The first pattern was positively associated with OW/OB at age 5 years (OR [95% CI] = 1.09 [1.03, 1.16] per 1-SD increase) and inversely associated with age at AR (β [95% CI] = - 12.1 days [- 19.1; -5.0] per 1-SD increase). No association was observed for the second LP. For the third pattern, no clear evidence of associations was found, although the effect sizes were comparable to those of the first LP (OR = 1.07 [0.99; 1.15]; β = -7.6 days [- 15.5; 0.3] per 1-SD increase). CONCLUSION: These results emphasize the perinatal period as a critical window for the emergence of interrelated lifestyle behaviors associated with OW/OB. They highlight the need for interventional studies to evaluate the effectiveness of early, integrated, multi-behavioral strategies to prevent childhood obesity.