Ethnic differences in maternal underestimation of offspring's weight: the ABCD study

To determine the ethnic variation in maternal underestimation of their child's weight status and the explanatory role of socio-economic status (SES), acculturation and parental body mass index (BMI).

A multi-ethnic sample of 2769 normal or overweight/obese children (underweight children excluded) aged 5-7 years was examined (The Amsterdam Born Child and their Development study), comprising five ethnic subgroups: Dutch (n=1744), African descent (n=184), Turkish (n=86), Moroccan (n=161) and other non-Dutch (n=592). Data on mothers' perception of their child's weight status (5-point scale from 'too low' to 'too high'), SES, acculturation, parental BMI and the children's height and weight were collected. Underestimation was defined by comparing maternal perception with the actual weight status of her child (International Obesity Task Force guidelines). Ethnic differences in underestimation were calculated in the normal weight and overweight/obese categories.

Underestimation ranged from 3.6 (Dutch) to 15.7% (Moroccan) in normal-weight children, and from 73.0 (Dutch) to 92.3% (Turkish) in overweight/obese children. After correction for ethnic differences in child's BMI, higher odds ratios (ORs) for underestimation were found in the Turkish (normal weight: OR 6.83; 95% confidence interval (CI) 2.33-20.05 and overweight: OR 2.80; 95% CI 1.12-6.98) and Moroccan (normal weight: OR 11.55; 95% CI 5.28-25.26) groups (reference is the Dutch group). Maternal educational level and immigrant generation largely explained the ethnic differences, with a minor contribution of maternal age. After correction, ORs remained higher in the Moroccan group (OR 4.37; 95% CI 1.79-10.62) among the normal-weight children.

Mothers frequently underestimate the actual weight status of their child, especially mothers from Turkish or Moroccan origin. Having a lower SES, being first-generation immigrant and a young mother are important determinants in explaining these differences. As weight perceptions may affect weight gain and almost all mothers of overweight/obese children underestimate their child's weight, health professionals should help mothers (particularly those from ethnic minority groups) to acquire a realistic perception of their children's weight status.