Website-based balanced nutritional education and its effect on knowledge and perception among early adolescents: a health belief model approach
DOI:
https://doi.org/10.22146/bkm.v42i07.29029Keywords:
balanced nutrition, early adolescent, health belief model, nutrition education, website mediaAbstract
Purpose: This study examined the effectiveness of a website-based balanced nutrition education program grounded in the Health Belief Model on the knowledge and perceptions of early adolescents, comparing it with conventional educational media.
Methods: This quasi-experimental, pre- test-posttest control group study was conducted in Sleman, Yogyakarta (February–May 2025). Junior high school students from SMPN 1 Mlati received the website-based nutrition intervention (three 30-minute sessions on days 1, 3, and 5), while those from SMPN 1 Seyegan served as the control group (conventional/printed media). Knowledge and perceptions were assessed using structured questionnaires before and after the intervention. Data were analyzed to evaluate within- and between- group changes.
Results: Both groups showed a significant increase in knowledge scores after the intervention (intervention: 39.90 to 48.43, Δ=8.53, p<0.001; control: 37.00 to 45.44, Δ=8.44, p<0.001). Perception scores also increased significantly in both groups (intervention: 48.28 to 52.27, Δ=3.99, p<0.001; control: 50.75 to 52.03, Δ=1.28, p=0.032). However, between-group analysis indicated no significant difference in knowledge improvement (p=0.911), whereas perception improvement was significantly greater in the intervention group (p=0.004). This finding suggests that website-based nutrition education serves as a more effective "cue to action" for fostering positive perceptions of balanced nutrition than conventional media.
Conclusion: Website-based balanced nutrition education is more effective at shaping students' perceptions than conventional media and holds potential as a theory-based school health promotion strategy.
References
Shapu RC, Ismail S, Ahmad N, Ying LP, Njodi IA. Knowledge, attitude, and practices of adolescent girls towards reducing malnutrition in Maiduguri Metropolitan Council, Borno State, Nigeria: a cross-sectional study. Nutrients. 2020;12(6):1681.
World Health Organization. Adolescent health. Geneva: WHO. Available from: [Website]
Zhou J, Li Y, Cai Y. Global burden of children and adolescents’ nutritional deficiencies from 1990 to 2021. Frontiers in Pediatrics. 2025;13:1583167.
United Nations Children’s Fund. Obesity exceeds underweight for the first time among school-age children and adolescents globally. 2025. Available from: [Website]
Kementerian Kesehatan Republik Indonesia. Survei Kesehatan Indonesia 2023. Jakarta: Kementerian Kesehatan RI; 2023.
Green EC, Murphy E, Gryboski K. Health Belief Model. In: Cockerham WC, Dingwall R, Quah S, editors. The Wiley Blackwell Encyclopedia of Health, Illness, Behavior, and Society [Internet]. Hoboken (NJ): John Wiley & Sons, Ltd.; 2026. Available from: [Website]
Tomé G, Matos M, Simões C, Diniz JA, Camacho I. How can peer group influence the behavior of adolescents: explanatory model. Global Journal of Health Science. 2012;4(2):26–35.
Siswati T, Kasdjono HS, Olfah Y, Paramashanti BA. How adolescents perceive stunting and anemia: a qualitative study in Yogyakarta’s stunting locus area, Indonesia. Aspirasi: Jurnal Masalah-Masalah Sosial. 2022;13(2):169–86.
Hargreaves D, Mates E, Menon P, Alderman H, Devakumar D, Fawzi W, et al. Strategies and interventions for healthy adolescent growth, nutrition, and development. The Lancet. 2022;399 (10320):198–210.
Rialihanto MP, Yudasari MG, Utami SB, Siswati T. Is a website more effective than WhatsApp? An experimental study to increase adolescent knowledge and perception about anemia. Hunan Daxue Xuebao/Journal of Hunan University Natural Sciences. 2023;60(08):36–45. Available from: [Website]
Brooks H, Irmansyah I, Renwick L, Lovell K, Halim DA, Arjadi R, et al. Evaluating a prototype digital mental health literacy intervention for children and young people aged 11–15 in Java, Indonesia: a mixed methods, multi-site case study evaluation. Child and Adolescent Psychiatry and Mental Health. 2023;17:79.
Caillaud C, Ledger S, Diaz C, Clerc G, Galy O, Yacef K. iEngage: a digital health education program designed to enhance physical activity in young adolescents. PLoS ONE. 2022;17(10):e0274644.
Lewis CC, Walsh-Bailey C, Lyon AR, Beidas R, Mittman B, Aarons GA, et al. Developing an educational resource aimed at improving adolescent digital health literacy: using co-design as research methodology. Journal of Medical Internet Research. 2024;26:e49453.
Alves SAA, Silva KL, Costa EAL, Mendes CKTT, Carvalho DPSRP, Araújo EC, et al. Digital booklet on sustainable practices for promoting adolescent health. Ciência & Saúde Coletiva. 2023;28(8): 2215–26.
Ernawati E, Baso YS, Hidayanty H, Syarif S, Aminuddin A, Bahar B. The effects of anemia education using She Smart on knowledge, attitudes, and practices among adolescent girls. International Journal of Health and Medical Sciences. 2022;5 (1):44–9.
Oddo VM, Maehara M, Rah JH, Ickes SB, Roshita A, Thow AM, et al. Evidence-based nutrition interventions improved adolescents’ knowledge and behaviors in Indonesia. Nutrients. 2022;14(9):1717.
Amahmid O, El Guamri Y, Rakibi Y, Ouazzani-Touhami K, Chtourou H, El Kettani M, et al. Nutrition education in school curriculum: impact on adolescents’ attitudes and dietary behaviours. International Journal of Health Promotion and Education. 2020;58(5):242–58.
Sau LYRL, Benu JMY, Artanti M. Conformity and cyber-aggression behavior in adolescent social media users. Journal of Health and Behavioral Science. 2025;7(3):858–68.
Chau MM, Burgermaster M, Mamykina L. The use of social media in nutrition interventions for adolescents and young adults. International Journal of Medical Informatics. 2018;120:77–91.
Dallagiacoma G, Alberti F, Odone A. The efficacy of digital media tools to promote a healthy diet in children: a systematic review of intervention studies. Acta Biomedica. 2023;94(Suppl 3):e2023157.
Marlinawati DA, Rahfiludin MZ, Mustofa SB. Effectiveness of media-based health education on stunting prevention in adolescents: a systematic review. AgriHealth. 2023;4(2):102–111.
Lemeshow S, Hosmer DW Jr, Klar A. Adequacy of sample size in health studies. England, USA: John Wiley and Sons Ltd; 1990.
Philippou E, Middleton N, Pistos C, Andreou E, Petrou M. The impact of nutrition education on nutrition knowledge and adherence to the Mediterranean diet in adolescent competitive swimmers. Journal of Science and Medicine in Sport. 2017;20(4):328–32.
Coffey AB, Alai NL, Gray VB, Cotter JA, Barrack MT. Nutrition education curriculum promotes adolescent runners’ self-efficacy, knowledge, and intake of nutrient-rich carbohydrate foods. Journal of the American Nutrition Association. 2023;42(2): 178–186.
Mayer RE. Multimedia learning. 2nd ed. New York: Cambridge University Press; 2009.
Chaeruman UA, Saputra SD. Cognitive theory of multimedia learning. 2021. Available from: [Website]
Chatterjee A, Prinz A, Gerdes M, Martinez S. Digital interventions on healthy lifestyle management: systematic review. Journal of Medical Internet Research. 2021;23(11):e26931.
Siswati T, Sitasari A, Paramashanti BA, Tjaronosari T, Nurhidayat N, Wijanarka A, et al. Effect of mHealth-based intervention on maternal knowledge and practices of child care: a quasi-experimental study. Public Health of Indonesia. 2024;10(1):10–20.
Seiterö A, Henriksson P, Thomas K, Henriksson H, Löf M, Bendtsen M, et al. Effectiveness of a mobile phone-delivered multiple health behavior change intervention (LIFE4YOUth) in adolescents: randomized controlled trial. Journal of Medical Internet Research. 2025;27:e69425.
Kok Wah JN. Empowering minds: how social support drives digital mental health engagement. Frontiers in Public Health. 2025;13:1565327.
Stauch L, Renninger D, Rangnow P, Hartmann A, Fischer L, Dadaczynski K, et al. Digital health literacy of children and adolescents and its association with sociodemographic factors: representative study findings from Germany. Journal of Medical Internet Research. 2025;27: e69170.


