Socioeconomic inequalities in the food environment and body composition among school-aged children: a fixed-effects analysis

BACKGROUND: There is limited evidence regarding socioeconomic inequalities of exposure to the food environment and its contribution to childhood obesity. METHODS: We used data from 4235 children from the Generation R Study in Rotterdam, The Netherlands. We included 11,277 person-observations of BMI and 6240 person-observations of DXA-derived FMI and FFMI between ages 4–14 years. Linear regression models evaluated changes in relative and absolute exposure to fast-food outlets and the healthiness of the food environment within 400 m of home by maternal education. Individual-level fixed-effects models assessed whether changes in the food environment were associated with changes in BMI, FMI and FFMI. RESULTS: Children of lower educated mothers were exposed to more fast-food outlets at all time-points. Over a median 7.1 years, absolute (+0.6 outlets; 95% CI: 0.4–0.8) and relative (+2.0%-points; 95% CI: 0.7–3.4) fast-food exposure increased more for children of lower versus higher educated mothers. The food environment became more unhealthy over time, with no differences in healthiness trends by maternal education. Changes in the food environment were not associated with subsequent changes in BMI, FMI or FFMI overall. Among children of lower educated mothers without initial fast-food exposure, the introduction of fast-food outlets was associated with small increases in BMI. CONCLUSIONS: Findings indicate widening inequalities in exposure to fast-food within an already poor food environment. Additional access to fast-food outlets does not appear to further impact BMI in contexts with ubiquitous fast-food availability.

Famke J. M. Mölenberg, Joreintje D. Mackenbach, Maartje P. Poelman, Susana Santos, Alex Burdorf, Frank J. van Lenthe