To apply FFQ, knowledge about portion sizes is relevant. According to increased energy and nutrient requirements, average portion sizes of foods are supposed to increase during growth. We provide empirically derived portion sizes for 4- to 18-year-olds in different age groups to facilitate analyses of FFQ data in children and adolescents.

Using data from the dynamic DOrtmund Nutritional and Anthropometric Longitudinally Designed cohort study, quantile regression for smoothing percentiles was used to derive portion sizes as a function of age from which age- and food group-specific portion sizes were calculated as median food group intake (g).

Dortmund, Germany.

Data from 3-day weighed dietary records (WDR) of 1,325 participants (♀: 653) were analysed. Participants provided in total 9,828 WDR (on average 7·5 per participant) between 1985 and 2022. WDR were grouped into five age groups, whereby each age group covered 3 years of age.

In total, 11 955 food items were reported and categorised into sixteen major food groups with seventy-one sub-groups. Portion sizes tended to increase with age, except for milk- and plant-based alternatives. Comparing 4- to 6-year-olds to 16- to 18-year-olds, portion size increased between 22·2 % (processed meat: 18 g v. 22 g) and 173·3 % (savoury snacks: 15 g v. 41 g).

We provide empirically derived portion sizes for children and adolescents. These data are useful to establish dietary assessment methods based on estimates of portion sizes, such as FFQ, for children and adolescents.