Effects of lifestyle-based interventions to improve Mediterranean diet adherence among the young population: a meta-analysis of randomized controlled trials.

Context: Despite the large number of studies published to date, the effect of lifestyle-based interventions on improving adherence to the Mediterranean diet (MedDiet) in young people has not been meta-analyzed.

Objective: The aim of the present systematic review and meta-analysis was two-fold: (1) to determine the pooled intervention effects of lifestyle-based interventions on improving adherence to the MedDiet in a young population aged 3 years-18 years and (2) to examine the potential factors related to those intervention effects.

Data sources: A systematic search of the MEDLINE (via PubMed), Scopus, Cochrane Library, and Web of Science databases was performed from their inception until June 15, 2023.

Data extraction: Different meta-analyses were independently performed to observe the effect of lifestyle-based interventions on adherence to the MedDiet (according to the Mediterranean Diet Quality Index in children and adolescents [KIDMED]).

Data analysis: Compared with the control group, the intervention group showed a small increase in KIDMED score (d = .27; 95% confidence interval [CI], .11 to .43; P < .001; I2 = 89.7%). Similarly, participants in the lifestyle-based intervention groups had a 14% higher probability of achieving optimal adherence to the MedDiet (risk difference = .14; 95% CI, .02 to .26; P = .023; I2 = 96.8%). Greater improvements in achieving optimal adherence to the MedDiet were found in interventions delivered out of school (risk difference = .24, 95% CI, .04 to .44; I2 = 88.4%), those aimed at parents or at both children and parents (risk difference = .20, 95% CI, .07 to .34; I2 = 98.2%), and those including only participants with overweight/obesity (risk difference = .34, 95% CI, .15 to .52; I2 = .0%).

Conclusion: Healthy lifestyle-based interventions seem to be effective in increasing adherence to the MedDiet and in achieving optimal adherence to this dietary pattern among children and adolescents.

Systematic review registration: PROSPERO registration no. CRD2022369409.