The aim of this paper was to systematically review the published evidence on the relationship between the type of childcare and risk of childhood overweight or obesity. The databases PubMed, MEDLINE, Cochrane Library and EMBASE were searched using combinations of the various search terms to identify eligible observational studies published between 2000 and May 2016 in English. Fifteen publications from 7 countries matched the inclusion criteria. The most commonly reported childcare arrangements were centre-based (e.g. crèche) and informal care (e.g. relatives, neighbours, friends). Informal care was most frequently associated with an increased risk of childhood overweight and obesity. Associations were also found for other lifestyle variables such as low maternal education, high birth-weight, maternal employment, ethnicity, maternal overweight/obesity and father's Body Mass Index (BMI).
Conclusion: The relationship between childcare and childhood overweight/obesity is multi-faceted with many aspects linked to childhood adiposity, in particular the age of initiation to care, type of care (i.e. informal care) and shorter breastfeeding duration were related with infant adiposity.
What is known: • Lifestyle factors during early years affect health outcomes in adulthood, particularly in children with low birth weight. • Pre-school stage influences children's body composition and growth. What is new: • This is the first systematic review of observational studies examining the association between childcare and childhood overweight and obesity in preschool children. • 'Informal' care is linked to early introduction to solid foods, less physical activity and obesity.
Keywords: Adiposity; Childcare; Childhood obesity; Childhood overweight; Review.