Parent-Child association in body weight status.

BACKGROUND: The prevalence of overweight and obesity among children and adults has risen in Canada. Studies suggest that parent obesity is a risk factor for overweight and obesity in children. This analysis examines associations between biological parent and child body mass index (BMI) in a nationally representative sample of Canadian children.

DATA AND METHODS: The analysis is based on data collected for 1,563 children aged 6 to 10 in the first three cycles of the Canadian Health Measures Survey (2007 to 2013). BMI was calculated using measured height and weight. Pearson correlation, logistic, and linear regression analyses examined associations between biological parent and child BMI and obesity status, controlling for other risk factors.

RESULTS: Biological parent and child BMI were correlated. When risk factors were taken into account, a child's average BMI increased as their parent's BMI increased. Parent BMI explained 2% of the variance in boys' BMI and 12% of the variance in girls' BMI. Boys and girls with a biological parent who was obese were at increased risk of being overweight or obese. Girls were also at increased risk of being overweight or obese if a biological parent was overweight.

INTERPRETATION: Children's body weight status is associated with that of at least one of their biological parents. Having an obese parent increases the risk of overweight or obesity among children in Canada.