Improvements in School Food Offerings over Time: Variation by School Characteristics.

The 2010 Healthy, Hunger-Free Kids Act (HHFKA) improved the nutritional quality of food served in schools. This longitudinal study examined school food offerings over time from school year 2010-11 to 2017-18 in public schools (n = 148) in four New Jersey cities. Six food indices were used to assess the number of healthy and unhealthy items offered as part of the National School Lunch Program (NSLP), in vending machines, and à la carte (i.e., competitive foods). Multilevel, multivariable linear regression with quadratic terms was used to model the trends over time. Interaction terms were added to examine whether the time trends varied by school-level factors, such as proportion of students eligible for free or reduced-price meals (FRPMs), race/ethnicity of enrolled students, and school level. Over the study period, healthy items offered in the NSLP increased ( < 0.001), while unhealthy items in the NSLP decreased ( < 0.001). Significantly different rates of declines in NSLP unhealthy offering were observed among schools at the two extremes of FRPM eligibility ( < 0.05). The trends for healthy and unhealthy foods offered in competitive foods showed significant non-linear trends, and differences were observed for school-level race/ethnicity, with worse outcomes for schools with majority Black student enrollment.