Healthy lifestyle in the first 1000 days and childhood overweight and obesity in 4 European cohorts

BACKGROUND: The high prevalence of overweight and obesity in young children suggests the involvement of early life exposures. Based on the Developmental Origins of Health and Disease paradigm, we investigated associations of healthy lifestyle (HL) behaviours around the first 1000 days of life with adiposity and weight status throughout childhood. METHODS: Cohort-specific analyses were conducted in four European birth cohorts (EDEN, Elfe, France; Generation R, the Netherlands; Lifeways, Ireland), implementing a harmonized data and analysis approach. Composite HL scores were calculated during pregnancy (maternal/parental) and infancy periods based on parental diet quality, BMI, smoking status, alcohol consumption; and for infant score breastfeeding, age of solid food introduction and exposure to passive smoking. Associations with child BMI (measure of overweight and obesity) and waist-to-height ratio (WHtR, measure of abdominal obesity) at age 5 and 9 were assessed using linear (BMI z-scores and WHtR) and logistic regression (IOTF categories). RESULTS: Current results are based on the Lifeways data; other cohort-specific analyses are ongoing. Depending on the period, up to 50% of the sample had unfavourable lifestyle factors, determined by a HL score of less than half of the possible points. Lower maternal and parental pregnancy HL scores, indicating lower adherence to HL factors, were associated with a higher child BMI at age 5 and 9. Associations with WHtR were non-significant. A low infancy HL score was strongly and consistently associated with both a higher child BMI and WHtR at age 5 and 9. CONCLUSIONS: A low adherence to HL factors around the first 1000 days of life was associated with a higher risk of childhood obesity. If confirmed in the other birth cohorts, these findings will inform the development of future early family-based lifestyle obesity prevention interventions. KEY MESSAGES: • Low adherence to healthy lifestyle behaviours around the first 1000 days of life is associated with a higher risk of childhood obesity and abdominal adiposity. • If confirmed in the other cohorts, these results call for further research exploring family and multi-behavioural approaches to prevention of childhood obesity.