Objective: To verify the efficacy of school-based interventions aimed at reducing sugar-sweetened beverage (SSB) consumption among adolescents in order to develop or improve public health interventions.Design: Systematic review of interventions targeting adolescents and/or the school environment.Setting: The following databases were investigated: MEDLINE/PubMed, PsycINFO, CINAHL and EMBASE. Proquest Dissertations and Theses was also investigated for unpublished trials.Subjects: Adolescents were defined as individuals between the ages of 12 and 17 years.Results: A total of thirty-six studies detailing thirty-six different interventions tested among independent samples (n152 001) were included in the review. Twenty interventions were classified as educational/behavioural and ten were classified as legislative/environmental interventions. Only six interventions targeted both individuals and their environment. Over 70 % of all interventions, regardless of whether they targeted individuals, their environment or both, were effective in decreasing SSB consumption. Legislative/environmental studies had the highest success rate (90·0 %). Educational/behavioural interventions only and interventions that combined educational/behavioural and legislative/environmental approaches were almost equally effective in reducing SSB consumption with success rates of 65·0 and 66·7 %, respectively. Among the interventions that had an educational/behavioural component, 61·5 % were theory-based. The behaviour change techniques most frequently used in interventions were providing information about the health consequences of performing the behaviour (72·2 %), restructuring the physical environment (47·2 %), behavioural goal setting (36·1 %), self-monitoring of behaviour (33·3 %), threat to health (30·6 %) and providing general social support (30·6 %).Conclusions: School-based interventions show promising results to reduce SSB consumption among adolescents. A number of recommendations are made to improve future studies.
Genome-wide association studies (GWASs) have identified several genes associated with obesity. The mechanisms through which these genes affect body weight are not fully characterized. Recent studies suggest that eating behavior (EB) traits could be involved, but only a few EB traits were investigated. This study aimed to investigate whether genetic susceptibility to obesity is mediated by EB traits (cognitive restraint, disinhibition, hunger) and their subscales. We hypothesized that EB traits, and their subscales, partly mediate this association. Adult individuals (n = 768) who participated in the Quebec Family Study were included in this cross-sectional study. A genetic risk score (GRS) of obesity was calculated based on the 97 genetic variants recently identified in a GWAS meta-analysis of body mass index (BMI). EB traits and their subscales were assessed with the use of the Three-Factor Eating Questionnaire. Regression analyses with age and sex as covariates were used to investigate the associations between GRS, EB traits, BMI, and WC and whether the association between GRS and obesity is mediated by EB traits, which represents the indirect effect of GRS on obesity. The GRS of obesity was positively associated with BMI (β = 0.19 ± 0.04, P < 0.0001) and WC (β = 0.46 ± 0.10, P < 0.0001). Regression analyses also revealed that the association between GRS of obesity and BMI was partly mediated by disinhibition and susceptibility to hunger (βindirect = 0.09 ± 0.03, P = 0.0007, and βindirect = 0.04 ± 0.02, P = 0.02, respectively). Habitual and situational susceptibility to disinhibition (βindirect = 0.08 ± 0.03, P = 0.002 and βindirect = 0.05 ± 0.02, P = 0.003, respectively) as well as internal and external locus of hunger (βindirect = 0.03 ± 0.02, P = 0.03 for both) were also found to mediate the association between GRS of obesity and BMI. The same trends were observed with WC. The results of this study indicate that the genetic susceptibility to obesity is partly mediated through undesirable EB traits, which suggests that they could be targeted in obesity treatment and prevention. This trial was registered at clinicaltrials.gov as NCT03355729.