Does school lunch equalize? An examination of dietary quality and socioeconomic disparities in Germany

An adequate diet is essential for children’s cognitive, physical, and educational development, yet children from lower socioeconomic backgrounds are more likely to have poorer dietary quality, reinforcing social inequalities. This study examines whether the offer of school lunch can mitigate the effect of socioeconomic status on children’s total daily dietary quality. Using food frequency data from the second wave of the German KiGGS study (2014–2017), we construct an updated Healthy Nutrition Score for Kids and Youth (HuSKY) to capture overall dietary quality in a single measure. We focus on children between 6 and 13 years and proxy school lunch using attendance at after-school care facilities that typically offer school lunch. To address potential selection bias between children with and without such a lunch offer, we apply propensity score matching. We then estimate a mixed-effects model on the matched sample (n = 2,212) to analyze the effects of socioeconomic status, school lunch offer, and their interaction on total daily dietary quality. Our results corroborate that dietary quality is higher among children with higher socioeconomic status and is also positively associated with receiving a school lunch offer. Beyond supporting prior findings, we find that the positive association between socioeconomic status and dietary quality is substantially weaker among children receiving a school lunch offer. Accordingly, we conclude that school lunch may help reduce socioeconomic disparities in dietary quality. Future research should examine whether these improvements help reduce broader inequalities in health, education, and income. Policymakers should consider these potential benefits in the ongoing debate surrounding (free) school lunch provision.