Brief Communication

Parents’ considerable underestimation of sugar and their child’s risk of overweight

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High sugar intake is associated with an increased risk of overweight. For parents, as their children’s nutritional gatekeepers, knowledge about sugar is a prerequisite for regulating sugar consumption. Yet little is known about parental ability to estimate the sugar content of foods and beverages and how this ability is associated with children’s body mass index (BMI). In 305 parent–child pairs, we investigated to what extent parents systematically under- or overestimate the sugar content of foods and beverages commonly found in children’s diets as well as potential associations with children’s z-BMI. Parents considerably underestimated the sugar content of most foods and beverages (e.g., 92% of parents underestimated the sugar content of yogurt by, on average, seven sugar cubes). After controlling for parental education and BMI, parental sugar underestimation was significantly associated with a higher risk of their child being overweight or obese (odds ratio = 2.01). There was a small dose–response relationship between the degree of underestimation and the child’s z-BMI. These findings suggest that providing easily accessible and practicable knowledge about sugar content through, for instance, nutritional labeling may improve parents’ intuition about sugar. This could help curtail sugar intake in children and thus be a preventive measure for overweight.

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We thank Kai Kolpatzik for helpful discussions about the design of this study.


This study did not receive financial support from any third party.

Author information


  1. Center for Adaptive Rationality, Max Planck Institute for Human Development, Berlin, Germany

    • Mattea Dallacker
    • , Ralph Hertwig
    •  & Jutta Mata
  2. Department of Health Psychology, University of Mannheim, Mannheim, Germany

    • Jutta Mata


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Conflict of interest

The authors declare that they have no conflict of interest.

Corresponding author

Correspondence to Mattea Dallacker.

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