Influence of Siblings on Child Health Behaviors and Obesity: A Systematic Review

Family structure plays an important role in childhood obesity but the association between having siblings and childhood obesity is not well established. The purpose of this systematic review was to examine the relationship between sibling factors and child health behaviors and child obesity. CINAHL, Cochrane Reviews, PsycINFO and PubMed were searched to identify relevant publications between 2000 and 2016. Of 141 identified studies, 22 peer-reviewed, primary research reports satisfied inclusion criteria and were included in the review. Findings indicated that children without siblings are more likely to be overweight or obese. Having fewer siblings was associated with decreased physical activity, inadequate sleep, and unhealthy dietary habits. The relationship between the number of siblings and childhood obesity persisted over time. All but two studies reported an association between birth order and childhood obesity. Youngest siblings were at a higher risk of becoming overweight or obese than their older siblings. Overall, the findings emphasize the importance of sibling factors in the development of childhood obesity. Further studies are needed to understand the dynamics underlying the effect of siblings on child’s health-related behaviors in order to develop effective childhood obesity prevention programs. Healthcare professionals should focus on family structure and at-risk children when intervening to prevent childhood obesity.