"Competitive" food and beverage policies and weight status: A systematic review of the evidence among sociodemographic subgroups

Abstract

Prior studies identified variable associations between competitive food and beverage policies (CF&B) and youth obesity, potentially due to differences across population subgroups. This review summarizes the evidence on associations between CF&B policies and childhood obesity within gender, grade level/ age, race/ethnicity, and/or socioeconomic levels. PubMed, EMBASE, CINAHL, and ERIC database searches identified studies published in English in Canada and the United States between January 1, 2000, and February 28, 2022. Of the 18 selected studies, six were cross-sectional, two correlational, nine were before/after designs, and one study utilized both a cross-sectional and pre-post design. Twelve studies reported findings stratified by a single sociodemographic factor, with grade level/age as the most frequently reported. Although the evidence varied, greater consistency in direction of associations and strengths of evidence were seen among middle school students. Six studies reported findings jointly by multiple sociodemographic subgroups with evidence suggesting CF&B associations with slower rate of increase or plateaus or declines in obesity among multiple subgroups, though the strengths of evidence varied. Over the past two decades, there have been relatively limited subgroup analyses on studies about CF&B policies and childhood obesity. Studies are needed with stronger designs and analyses disaggregated, particularly by race/ethnicities and socioeconomic factors, across places and time.

Keywords: demographic subgroups; nutrition policies; obesity.

Figure 1:

PRISMA 2020 flow diagram for systematic review, which included searches of databases, registers and other sources. From: Page MJ, McKenzie JE, Bossuyt PM, Boutron I, Hoffmann TC, Mulrow CD, et al. The PRISMA 2020 statement: an updated guideline for reporting systematic reviews. BMJ 2021;372:n71. doi: 10.1136/bmj.n71. For more information, visit: http://www.prisma-statement.org/

Figure 2:

Number and types of socio-demographic subgroup analyses reported in the selected studies.^{a a} Number does not add up to 18 studies because some studies reported results separately for more than one demographic subgroup, e.g., gender or race/ethnicity. ^b Multiple-sociodemographic subgroups include combinations of two or more social factors jointly or in stratified analyses by: grade and gender (Bauhoff, 2014; Sanchez-Vaznaugh et al, 2010); grade, gender and race/ethnicity (Matsuzaki et al, 2021; Sanchez-Vaznaugh et al, 2021), grade, gender and school-neighborhood income (Sanchez-Vaznaugh et al, 2015) and gender and urbanicity (Matsuzaki et al, 2022).