Fortification masks nutrient dilution due to added sugars in the diet of children and adolescents.

High intakes of added sugars have often been suspected of lowering nutrient density, especially in the diet of children and adolescents. Because fortified foods, which currently contribute considerably to the intake of vitamins and minerals, are often also sweetened with added sugars, they could counteract this nutrient dilution. Data from the DOrtmund Nutritional and Anthropometric Longitudinally Designed (DONALD)-Study were used to assess the effects of added sugars, fortified food and energy intakes, time and age on nutrient densities. A total of 4993 3-d weighed dietary records from 849 children and adolescents 2-18 y old, collected between 1985 and 2001 were analyzed using a mixed linear model, in which the means of the data and the covariance structure specific to the DONALD-Study was modeled. In general, nutrient densities in the diets of children and adolescents were above recommended nutrient densities. Added sugars intake [in percentage of energy intake (E%)] was positively associated with energy intake (MJ/d; P < 0.05) and intake of fortified food (E%; P < 0.0001). Positive effects of fortification on nutrient densities (usually P < 0.0001) exceeded the negative effects of added sugars intake (usually P < 0.01) for most nutrients, in some cases even twofold. Associations between energy intake and nutrient densities were negative and, with the exception of thiamin in 2- to 3-y-olds, statistically significant. Time and age trends were heterogeneous. Our data did not show significant nutrient dilution because of added sugars. The positive effect of fortification on nutrient densities was greater than the negative effect of added sugars. Therefore, fortification should more often be considered in dietary analyses.