Nutrition education and behavioral interventions in youth team-sport and related development settings: a systematic review of nutrition knowledge, dietary behaviors, hydration, body composition, and performance

TL;DR

This PRISMA-registered systematic review synthesized 27 unique intervention studies (1,799 athlete participants) of nutrition education, hydration education, counseling, digital tools, and multicomponent programs in youth team-sport and related development settings. Nutrition and sports nutrition knowledge improved most consistently, while effects on dietary intake, body composition, biochemical markers, and performance were mixed; hydration showed the clearest short-term objective changes when education was paired with practical cues, fluid access, feedback, or individualized prescriptions.

Key findings

• Nutrition/sports nutrition knowledge was the outcome with the most consistent favorable changes across workbook, classroom, digital, counseling, and dietitian-led programs. Examples: Nascimento et al. reported adolescent total knowledge rising from 73.6 ± 15.0 to 84.6 ± 11.0 (p < 0.05); Stewart et al. reported knowledge increasing at 6 weeks (13.22 ± 4.41 to 21.56 ± 9.29; p < 0.01) but not at 12 weeks (14.50 ± 5.18 to 15.42 ± 3.95; p = 0.38); IDEHA-F found higher post-intervention knowledge in the intervention vs. control group (3.42 vs. 2.53/5; p < 0.001) but did not measure baseline knowledge.
• Knowledge gains did not reliably translate into dietary change. Zeng et al. improved knowledge without significant change in dietary behavior or adjusted Dietary Balance Index; Aytekin and Koç increased knowledge without significant Diet Quality Index change; Vicente et al. and Veloso-Pulgar and Farran-Codina improved knowledge without significant change in Mediterranean diet adherence, intake, or body composition.
• Hydration interventions produced the clearest short-term objective signals. Kavouras et al. improved urine specific gravity/osmolality and 600-m run performance with a lecture plus urine-color charts and improved water access; Atkins et al. improved urine specific gravity and water intake at 3 days but effects were attenuated at 24 days; Cleary et al. found a one-time education session alone insufficient to maintain body mass, whereas an individualized sweat-rate-based prescription was.
• Body composition, biochemical, and performance findings were inconsistent and often confounded by growth, maturation, co-interventions (e.g., FIFA 11+, vitamin D supplementation, controlled dietary modification), or lack of a comparator.

Methods

• Systematic review following PRISMA 2020, registered in PROSPERO (CRD420261441507); searches of PubMed/MEDLINE, Scopus, Web of Science Core Collection, SPORTDiscus/EBSCO, and Cochrane CENTRAL from inception to 31 July 2026 (abstract states 3 July 2026), with no date or language restrictions.
• Two reviewers independently screened, extracted data, and assessed risk of bias (RoB 2 for randomized trials; ROBINS-I or adapted ROBINS-I for non-randomized and before-after studies). Narrative synthesis was used because meta-analysis was not feasible.
• Searches identified 370 records (56 PubMed, 151 Scopus, 87 Web of Science, 41 SPORTDiscus/EBSCO, 35 Cochrane CENTRAL) per the Results section; after 165 duplicates removed, 205 records were screened, 46 full texts assessed, and 27 unique studies included (1,799 participants; 1,781 child/adolescent; female participants 32.2% of those with reported sex, 537/1,668). Note: the abstract reports 419 records, which is inconsistent with the Results section.

Limitations

• Stated: heterogeneity, small samples, short follow-up, incomplete intervention reporting, predominance of pilot and non-randomized designs, and inability to perform meta-analysis; formal GRADE ratings were not generated, so conclusions are descriptive rather than graded recommendations. Some studies were mixed-sport, recreational, school, or older development-phase contexts and thus indirect for competitive youth team sport. Several interventions combined education with training, supplementation, dietary modification, or environmental support, limiting causal attribution. The electronic search strategy used named sports and an outcome block, which may have reduced sensitivity, and one report could not be retrieved.
• Stated risk-of-bias findings: RoB 2 judgments of randomized studies were overall "some concerns"; ROBINS-I judgments for non-randomized and pre-post studies ranged from moderate to serious, with Nascimento et al. and Stewart et al. judged at serious overall risk.
• Evident from the text: dietary assessment relied on self-report (24-h recalls, food records, food-frequency/screening questionnaires, photographic records, diet-quality indices), which the authors note is vulnerable to reactivity, recall and social-desirability bias, and under-reporting; no included study used a formal multidimensional measure of nutritional health literacy; several body-composition findings were statistically significant but not interpretable given uncontrolled growth and maturation.