1. Introduction

During adolescence, psychological traits like independence, self-consciousness, and cognitive flexibility change significantly, and height and weight develop quickly ( 1 , 2 ). Adolescent growth and development depend heavily on healthy eating habits and nutritional status. On the other hand, poor eating habits can raise the chance of developing obesity and other long-term conditions ( 3 ). Any food consumed between main meals is considered a snack, contributing significantly to students’ caloric consumption. Environmental factors, behaviors, emotions, opinions, and those of significant others all impact how many snacks they eat at school ( 4 ). Notably, there were noteworthy correlations discovered between teenage girls’ depression ratings and snack eating ( 5 ). Furthermore, studies on meal patterns have shown that snacks are becoming more common, and their negative impacts on diet have been validated because of their high energy density and low nutritious content ( 6 ). Since it can significantly influence their future health, it is imperative to comprehend the connection between schoolchildren’s eating habits, snacks, and health ( 3 ).

Snacking between meals is common among adolescents ( 7 , 8 ). Healthy snacking can enhance adolescents’ overall nutritional quality and help them fulfill requirements for consuming essential food groups, like fruit ( 9 ). However, teenagers frequently snack on energy-dense snacks and sugar-sweetened beverages, which leads to low nutritional intake and a high prevalence of overweight/obesity ( 8 , 10 , 11 ). Unhealthy snacking among students has been shown in studies conducted around the globe. For example, a study conducted in Poland revealed that the most prevalent unhealthy snack among students was potato chips ( 12 ). Furthermore, candy, carbonated beverages, sweet drinks, and high-salt snacks were the most popular snacks among American teenagers ( 13 ). According to studies, children and teenagers in Iran also consume unhealthy snacks ( 14 , 15 ). Candy (30.8 and 33.2%), fizzy drinks (21.5 and 27.2%), cheese puffs, and potato chips (20.3% and 25.8%) were the most common unhealthy snacks in both urban and rural areas of Iran, according to a thorough analysis ( 4 ).

The failure of educational programs to promote healthy behaviors can be attributed, in part, to the neglect of psychosocial models and behavior-influencing elements as distinct conceptual frameworks in educational programming ( 16 ). By predicting the key aspects of healthy snacking behavior using the beliefs, attitudes, subjective norms, and enabling factors (BASNEF) model, we hope to close the gap. Programs that modify behaviors are studied using this concept. It also establishes standards, societal pressures, attitudes toward a habit, and the essential elements that help people engage in healthy activities. Fishbein’s hypothesis about attitude structures, behavioral intention, subjective norms, and enabling elements, including: time, expenditure, and behavior skill, forms the basis of the BASNEF model ( 17 ). Although the best indicator of behavior is a person’s desire to engage in it, attitudes and subjective standards can change behavioral intention, which in turn affects behavior performance ( 18 ). This trend has been identified in some previous studies ( 19 , 20 ).

The primary aim of this study was to explore the determinants of healthy snacking behavior among Iranian adolescent girls using the BASNEF model. Specifically, this study sought to identify the key factors influencing snacking behavior, including attitudes, subjective norms, enabling factors, and behavioral intention. This study also aimed to provide insights into how the BASNEF model can be applied to promote healthy snacking behaviors in this population and improve educational interventions to enhance adolescent nutrition.

2. Methods

This cross-sectional, descriptive-analytical study was conducted in the spring of 2020 on 420 female high school students in the Iranian capital, Saveh, Iran.

After carefully accounting for a 10% dropout rate, 420 people were finally included in the study. A thorough multistage sampling procedure was used to choose the study participants. At first, Saveh was separated into two separate districts: the core and outer districts. An extensive list of secondary schools in Saveh Education Department was later obtained. Twelve female schools were randomly selected from each district, yielding 24 high schools. The study samples (422 female students) were then chosen using a straightforward random sampling technique and included in the study in proportion to the number of students enrolled in different grades of 7th, 8th, and 9th. The female students in grades 1, 2, and 3 who had not previously dealt with mental or cognitive issues were included in the study. Every participant gave their written consent to take part in the study. Incomplete questions on the questionnaire led the participants being excluded from the study. The age range of the participants varied from 12 to 15 years old. As a result, all study participants provided written student assent and written parental informed consent forms.

2.1. Study Tools

The questionnaire used in this study was developed based on a systematic literature review and validated tools from previous studies ( 16 , 18 ). Questions were adapted to align with the constructs of the BASNEF model and tailored to the target population of high school female students. A panel of ten Nutrition, Psychology, and Health Education specialists evaluated the content validity using the Content Validity Index (CVI=0.58) and Content Validity Ratio (CVR=0.87). A pilot test with 50 students assessed reliability. The Cronbach’s alpha coefficients for the different parts ranged from 0.73 to 0.84, suggesting acceptable internal consistency.

The first section of the questionnaire focused on demographic data, including the mother’s occupation, BMI, and parents’ educational attainment. The second section was created using the BASNEF model elements. These constructs included behavioral intentions (9 questions) with a 5-point Likert scale, enabling factors (11 questions) with a three-point scale of “yes” (score 2), “somewhat” (score 1), and “no” (score 0), and attitudes (10 questions) with a 5-point Likert scale that ranged from “strongly agree” with a score of 5 to “strongly disagree” with a score of 1. In previous studies, the Cronbach’s alpha coefficient was used to assess the reliability of the questionnaire and values ranging from 0.71 to 0.89 were determined for each section. Also, the content validity of this questionnaire was confirmed by the content validity ratio (0.87) and content validity index (0.85).

The study focused on snack behavior, a significant aspect of adolescent dietary habits, particularly in high school-aged individuals in Iran. The study examined a variety of snacks, including homemade bites, nuts, dates, raisins, dried biscuits, dried fruit, and fruits and vegetables, which were categorized as healthy snacks. Unhealthy snacks included crisps, cheese puffs, industrial juices, soft drinks, sausage rolls, pastilles and candies, and stamps and plums. The frequency of snack consumption was recorded using a pre-designed table, with the number of snack times ranging from 0 to 7 times a week.

2.2. Data Analysis

The statistical software SPSS version 20.0 was used for all analysis. In addition to independent t and χ2 tests, descriptive statistics techniques were employed, including frequencies, mean and standard deviations. Multiple regressions were used for additional analysis.

The survey was distributed to the students following consultation with the education office officials and schools in the city. The self-reporting technique was employed to collect participant replies, and the researcher gave the required justifications for each question. The questionnaire did not include the participants’ names; other information was kept private and exclusively used for this study. Notably, out of the 433 students randomly selected based on the sample size, 420 students took part in the study while only 13 students did not complete the questionnaire (the response rate was roughly 97%) or did not participate due to their parents’ dissatisfaction.

3. Results

A total number of 422 students were selected and enlisted for the study; however, 12 cases were eliminated for not returning the questionnaires, and 15 participants were eliminated because their questionnaires were not completed. Data from 395 students—of whom 45.31% were male and 54.69% were female—were subjected to statistical analysis. All of the students were 14.10±2.30 years old on average. Of the participants, 51% were put into different weight groups, and 49% were classified as having an average weight (Table 1).

The mean score for the variables within the study’s theoretical framework in Table 2 showed no discernible differences between male and female students (P > 0.05). Analysis of correlation Pearson’s correlation matrix (Table 3) indicated that good and harmful snacking behaviors were substantially correlated with every BASNEF model variable. Subjective norms showed the most significant positive link with healthy snacking behavior (r=0.423, P<0.001), whereas behavioral intention showed the strongest negative correlation with unhealthy snacking behavior (r=−0.375, P<0.001).

According to multiple regression analysis, 27% of the variation in healthy snacking behavior could be explained by the BASNEF model. The importance of favorable attitudes and easily accessible resources in promoting healthy snack choices is demonstrated by the significant contributions of attitude (B=0.149, P<0.001) and enabling factors (B=0.230, P<0.001) among the linked components (Table 4).

For unhealthy snacking behavior, the regression model accounted for 21% of the variance (P < 0.001). The predictors include attitude (B=-0.094, P=0.04), behavioral intention (B=-0.129, P<0.001), and subjective norms (B=-0.216, P<0.001) (Table 5).

4. Discussion

The present study aimed to explore the associations between the BASNEF model constructs and snack consumption behaviors among adolescents. The findings revealed that the model accounted for 26% of the variance in healthy snack consumption behavior, with constructs such as attitude and enabling factors playing notable roles. Similarly, the model explained 21% of the variance in unhealthy snack consumption behavior, with significant contributions from attitude, social norms, and intention.

Attitude was identified as a critical factor for adolescents’ healthy snacking behavior. This aligned with prior studies ( 21 - 23 ), which highlighted the role of attitude in shaping dietary behaviors. Attitudes reflect an individual’s perception of the desirability or undesirability of an action, influencing behavioral intentions. While attitudes shaped by emotional and cognitive experiences are associated with healthier eating habits, it is essential to recognize the cross-sectional nature of this study, which limits causal interpretations.

Enabling factors also emerged as significantly associated with healthy snack consumption. These findings were consistent with prior research, such as the survey of Bîlbîie and colleagues in Romania ( 24 ), which highlighted the impact of resource availability on dietary behavior. For example, reducing the cost of healthier snack options could positively influence consumption patterns. However, further longitudinal studies are necessary to examine how changes in enabling factors translate into sustained behavior change.

Social norms showed a strong association with unhealthy snack consumption. This finding aligned with previous studies ( 24 - 26 ) and highlighted the influence of family, peers, and school environments on adolescents’ dietary behaviors. Notably, peer influence appeared to be a critical factor, underscoring the need for interventions targeting peer groups. The cross-sectional design precludes determining whether social norms directly lead to unhealthy snack consumption or whether shared behaviors reinforce norms within peer groups.

Intention also showed a significant association with unhealthy snacking behaviors. This supports the foundational role of intention in the BASNEF model, as noted in previous studies ( 27 , 28 ). Intention reflects the motivational factors behind the behavior. Yet, its relationship with actual behaviors may vary depending on external barriers or enablers. While the results suggested intention as a key intervention focus, longitudinal or experimental designs would be required to understand its predictive validity over time.

It is important to stress that the observed connections should not be regarded as causal relationships due to the cross-sectional design of this study. To investigate the causal pathways and temporal interactions between these characteristics and snacking behaviors, more studies using experimental or longitudinal methods are required. Furthermore, qualitative insights may help us better understand how context-specific factors, especially social and cultural dynamics, affect the food choices of adolescents.

4.1. Limitation

When evaluating the results, it is essential to consider the limitations of this study. First, Teenagers may not always provide accurate information about their snacking habits and the factors that influence them, as their self-reported data can be affected by biases, such as social desirability bias. Second, a longitudinal approach would offer a more thorough knowledge of how snacking patterns evolve, as the cross-sectional form of the study restricts the capacity to demonstrate causal links between the identified characteristics and snacking behaviors. Last but not least, while the study was conducted in Saveh, Iran, the results might not be applicable in other cultural or geographic contexts because social, environmental, and educational factors influencing teenage behavior may alter depending on the location.

5. Conclusion

This study highlighted the significant associations between the constructs of the BASNEF model and snack consumption behaviors among adolescents in Saveh, Iran. The findings underscored the importance of attitude and enabling factors in promoting healthy snack consumption and the role of social norms and intention in unhealthy snacking behaviors. While the cross-sectional nature of this study limits causal interpretations, the results suggested that interventions targeting attitudes, social norms, and enabling factors could be effective strategies for promoting healthier dietary choices among adolescents. Future longitudinal and experimental studies are essential to better understand the causal relationships between these factors and to develop more effective interventions tailored to adolescents’ unique cultural and social contexts. Additionally, exploring qualitative insights could further enrich our understanding of the factors influencing adolescent snacking behaviors.

Acknowledgment

We would like to thank all the participants who take part in the study.

Authors’ Contribution

Fatemeh Gudarzi: Contributed to the gathering and analysis of data; drafting the work and reviewing it critically for important intellectual content. Zahra Saboohi: Contributed to the design of the study; drafting the work and reviewing it critically for important intellectual content. Zahra Jalili: Contributed to the design of the study; drafting the work and reviewing it critically for important intellectual content. All authors have read and approved the final manuscript and agree to be accountable for all aspects of the work, such that the questions related to the accuracy or integrity of any part of the work.

Conflict of Interest

None declared.

Funding

None.

Ethical Approval

The ethics committee of the Islamic Azad University, Science and Research Branch of Tehran, Iran approved the research with the code of IR.IAU.TMU.REC.1398.153. Also, written informed consent was obtained from the participants.

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