The improvement of dietary behaviors among Iranian adolescent girls: a theory-based randomized controlled trial

Educational Nutritional Intervention Program for Adolescents Based on Social Cognitive Theory: Pilot Study of a Cluster Randomized Controlled Trial

The eating habits of adolescents are often inadequate, with high consumption of unhealthy foods and low consumption of healthy foods. It is necessary to design and implement effective interventions to improve eating habits at this age and evaluate their feasibility, acceptability, and effectiveness. The use of theories for behavior change in health interventions favors the adoption of healthy behaviors. Due to this, the objective was set to determine the feasibility, acceptability, and effect on food consumption of a new educational nutritional intervention program for adolescents based on the Social Cognitive Theory (SCT) and supported by the Trans-theoretical Model (TTM) and identify areas of improvement in study design and intervention for future larger-scale studies. A pilot study of a cluster randomized controlled trial was conducted in adolescents of both sexes, 12 to 15 years of age, students from a public secondary school in Tonala, Jalisco, Mexico. The results show that a nutritional education intervention for adolescents, based on SCT and supported by the TTM, is feasible, acceptable, and with positive results in the modification of the consumption of ultra-processed foods, vegetables/fruits, and water. This pilot study identified some aspects that could be improved to enhance the effectiveness of the interventions in future studies.

A systematic review of educational nutrition interventions based on behavioral theories in school adolescents

The purpose of this study was to summarize the evidence from studies conducted on adolescents, evaluating educational nutrition interventions for the modification of food consumption through controlled trials based on behavior change theories or models and implemented in school settings. A systematic search was carried out through PubMed and ERIC databases between November and December 2020, and updated in February 2023; English-language keywords were used, and no publication date limits were applied. Two authors independently performed the search, data extraction, data synthesis and risk of bias assessment. Twelve studies meeting the inclusion criteria were included. The interventions were based on different theories; the most used was the Social Cognitive Theory. Eleven of the twelve studies showed favorable modifications in the consumption of at least two of the food groups. Most studies were at low risk of bias, and only one was classified as high risk. It is concluded that educational nutrition interventions based on behavior change theories/models and implemented in the school setting influence positive changes in adolescents eating behavior.

Improving Obesogenic Dietary Behaviors among Adolescents: A Systematic Review of Randomized Controlled Trials

The overweight and obesity epidemic persists, and over 340 million children and adolescents aged 5–19 were classified as overweight or obese worldwide in 2020. Obesity intervention becomes crucial during the adolescent years due to the increased autonomy and adolescent motivation to oversee one’s own behaviors and lifestyle-related decisions. The objective of the current study was to conduct a systematic review of randomized controlled trials aimed at improving dietary intake and behaviors among adolescents. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines were utilized. The key terms used in the searches referred to the study population and the topic of interest and included words and phrases such as “obesity or overweight and adolescents”, “dietary behaviors and adolescents”, “dietary intake and adolescents”, and “dietary habits and adolescents.” A tertiary screening process was employed, and the National Heart, Lung, and Blood Institute Quality Assessment of Controlled Intervention Studies quality scoring tool was utilized to assess the quality of research articles independently by n = 2 researchers. A total of 7441 articles were identified through the database search, and 36 were included in the current systematic review. The most common outcomes explored included dietary behaviors, anthropometric or biometric outcomes, and physical activity. Approximately half of the studies demonstrated significant improvements in the primary outcomes investigated. The majority of the high-impact studies where significant improvements in primary outcomes were demonstrated were conducted in school settings or were multicomponent or multilevel in nature. Thus, interventions targeting dietary behaviors in adolescents that are delivered in the school setting and are multicomponent or multilevel in nature are the most effective in terms of impact on dietary intake, anthropometric or biometric outcomes, and physical activity.

Effect of School-Based Nutrition and Health Education for Rural Chinese Children

The nutritional status of rural Chinese children has improved in recent years, but their nutritional knowledge is still relatively lacking. School-based nutrition and health education was conducted for children in three counties of China from 2018 to 2020. The students in the intervention schools were given two-year nutrition and health education courses, while the control schools did not receive any intervention. Students’ nutrition knowledge, dietary intake, and dietary behaviors were collected using a questionnaire, and height and weight were measured uniformly. The nutrition knowledge score in the intervention group was increased by 1.01 and 0.64 points in the first and second years. A multilevel model was used to evaluate the intervention effects. Statistically significant interactions between groups and time were observed in nutrition knowledge, the frequency of eating breakfast, and dietary intake, including meat, eggs, milk, and vegetables (p < 0.05), but not in nutritional status. Therefore, the supplementation of school-based nutrition and health education had a positive impact on the nutrition knowledge and dietary intake of rural Chinese children.

Trends in the Number of Behavioural Theory-Based Healthy Eating Interventions Inclusive of Dietitians/Nutritionists in 2000-2020

Nutrition interventions developed using behaviour theory may be more effective than those without theoretical underpinnings. This study aimed to document the number of theory-based healthy eating interventions, the involvement of dietitians/nutritionists and the behaviour theories employed from 2000 to 2020. We conducted a review of publications related to healthy eating interventions that used behaviour change theories. Interventional studies published in English between 2000 and 2020 were retrieved from searching Medline, Cinahl, Embase, Psycinfo and Cochrane Central. Citation, country of origin, presence or absence of dietitian/nutritionist authors, participants, dietary behaviours, outcomes, theories and any behaviour change techniques (BCTs) stated were extracted. The publication trends on a yearly basis were recorded. A total of 266 articles were included. The number of theory-based interventions increased over the two decades. The number of studies conducted by dietitians/nutritionists increased, but since 2012, increases have been driven by other researchers. Social cognitive theory was the most used behaviour theory. Dietitians/nutritionists contributed to growth in publication of theory-based healthy eating interventions, but the proportion of researchers from other professions engaged in this field increased markedly. The reasons for this growth in publications from other professions is unknown but conjectured to result from greater prominence of dietary behaviours within the context of an obesity epidemic.

Sustainability of a Multi-Component Education Program (ABC of Healthy Eating) after Three Months and Nine Months: The Socioeconomic Context in Improving Nutrition Knowledge in Polish Teenagers

The study aimed to evaluate the sustainability of a multi-component education (ABC-HEat) program related to healthy nutrition and lifestyle after three months and nine months and to assess the socioeconomic context in improving teenage nutrition knowledge. The study was designed as a clustered, controlled, education-based intervention. A sample was chosen and allocated into either an educated group (under intervention) or a control group (outside of intervention). The study covered 464 11–12-year-old students (educated/control 319/145). In the educated group, data were collected three times: before education, after three months and after nine months to measure the short- and the long-term effects of education, respectively. In the control group, data were collected in parallel. Changes in nutrition knowledge score (NKS, points) by sex, residence, family affluence scale (FAS) were the main outcome measures. The increase in the NKS was significantly higher in the educated group than in the control group—three months after education on average by 1.4 to 2.7 points (all p < 0.001) in the total sample and all subgroups, and nine months after education in rural residents by 2.2 points (p < 0.001) and in the total sample by 0.4 (p < 0.05). In the educated group, the chance of no increase in the NKS was higher in urban than rural residents after three months and nine months (adjusted odds ratios [OR] and 95% Confidence Intervals [95% CI]: 3.63, 1.80–7.31 and 2.99, 1.60–5.59, respectively, both p < 0.001) using the increase in the NKS by ≥4 points as a reference. The multi-component education program improved the nutrition knowledge of teenagers in the short term regardless of socioeconomic variables, but in the long term this effect was visible only in rural residents. It suggests that a special path of nutrition education addressed to urban teens may be required.