Background
Obesity is a serious public health problem that affects different age groups worldwide. Surveys on health and nutritional status of Brazilian students have shown an exponential growth in the prevalence of overweight and obesity in recent decades [
1‐
3]. This situation has important health implications [
4] and results from multiple factors, including modifiable conditions such as an inadequate diet. As the literature clearly demonstrates, the high consumption of ultra-processed foods correlates with the prevalence of overweight and obesity among adolescents and adults [
5‐
10].
The dietary practices of Brazilian adolescents are frequently considered inappropriate because they include regular intake of soft drinks, artificial juices, sweets, sugar, and fried and high-fat foods; low intake of fruits and vegetables; and irregular eating habits, as meals are replaced with snacks and breakfast is missed [
1‐
3,
11‐
13]. The Brazilian Study of Cardiovascular Risks in Adolescents (ERICA), with 71,791 participants, reported that the consumption of saturated fats, sugar and sodium was higher than the recommended upper limits; conversely, the recommended consumption of calcium and vitamins A and E was not reached [
14].
Coping with that public health issue is a major challenge because eating behavior is influenced by the dietary environment and by social, cultural, and infrastructure conditions [
15]. Current World Health Organization (WHO) guidelines indicate that a set of regulatory provisions, educational actions, and breastfeeding and healthy diet measures should be adopted to prevent obesity in children and adolescents [
16].
Dietary guidelines are food and nutrition education (FNE) tools aimed at promoting healthy lifestyles and preventing diet-related diseases at the individual and collective level [
17]. In Brazil, the
Dietary Guidelines for the Brazilian Population provide a framework for educational actions, and their implementation should be based on the use of methods that encourage people to discuss and understand the concepts involved in eating behavior [
18,
19]. To disseminate their content, some aspects should be considered, including the social market and the available technological innovations [
20], such as the Internet and mobile devices (tablets and smartphones) [
21].
Mobile health (mHealth) integrates mobile technology with public health practices with the purpose of improving communication and achieving healthy lifestyles [
22]. Studies have reported that mHealth interventions may increase access to health care services; initiate the process of behavior changes or increase motivation for small changes; and spread knowledge, especially if aimed at receptive consumers [
23‐
26]. Adolescents and young adults form the audience that readily accepts and adopts new technologies; thus, the diffusion effect may be stronger among them [
27].
When assessing behavior changes in the field of food and nutrition, another important term is mobile nutrition, or mNutrition. This type of technology is based on repeated contact and exposure to messages that increase knowledge and raise awareness about nutrition, being a useful tool to change attitudes and support healthier lifestyles in terms of dietary habits [
28,
29].
Currently, there is consistent evidence of the benefits of using mobile tools to improve health behaviors, especially when they are developed within a theoretical framework [
30]. According to Sparapani [
31], social cognitive theory [
32] can be applied in health promotion to link interactive technologies and behavior changes. However, studies assessing the effectiveness of such interventions are still scarce [
29,
33], requiring further research [
34,
35]. Recently, Melo et al. [
30] systematically reviewed 11 studies on the use of technologies in nutritional interventions for adolescents. The authors suggest that long-term interventions tend to be more successful when they involve frequent exposure to technological resources and a theoretical component aimed at a single health behavior change. The most commonly used theoretical framework in the reviewed studies was social cognitive theory.
mHealth strategies include the use of mobile applications (apps) as a resource for health improvement [
36]. These mHealth apps have been increasingly downloaded [
37], including digital games [
38,
39]. In their review, Melo et al. [
30] indicated that games seem to be promising tools for nutritional interventions, as all reviewed studies using this type of technology were effective, especially among young people.
Games are interactive systems that allow a more flexible relationship with the content, thus the player takes the leading role in the learning process. Their potential contribution depends on the player’s comprehension of the concept of the game and on the process of game design and its consequences [
40,
41]. Schell [
40] says that interactivity is a key element to understand the game. Without its interactive nature, the game becomes a linear narrative, similar to videos or books [
42].
To be an engaging learning experience, the game must have the following attributes: gameplay, rules, goals, interactions, adaptations, actions, feedback, winning, conflicts, resolutions, and interpretations, all of them working interconnected [
39]. Games designed to improve people’s cognitive and intellectual skills [
43] are called educational games, learning games, or serious games [
38,
44]. Several benefits have been attributed to game-based learning [
43,
45,
46], including changing people’s behavior [
44,
47], which justifies its increasing importance in the game industry [
48].
To actually play the game, the player must be driven by an intrinsic motivation, i.e., the sense of pleasure generated by the interaction [
49]. The fascinating feature of the game is responsible for conducting the player’s experience in the universe of the game. The boundary between the game world and the real world is called the magic circle [
50]. Because the act of staying in the magic circle is voluntary, the game must be designed to provide a comprehensive experience [
51], in a process known as game design.
Game design is the art of organizing and aligning the different elements that form a game, which are known as the elemental tetrad and include story, aesthetics, mechanics, and technology [
40]. With respect to the game mechanics, the process of learning how to play the game should provide the intended knowledge and skills [
52]. The player’s immersion is based on the process of regulation of the difficulty level presented by the game [
40,
42,
53]; thus, hard games may cause frustration while very easy games may be tedious [
54]. Regarding the story, there is a strong need to plan a transversal progression throughout the game [
55], which allows a fluid immersion of the player in the magic circle.
Several FNE actions have been described in the literature; however, the challenge of adapting food and nutrition guidelines to achieve effective changes in health behavior remains [
12], especially when involving the adoption of innovative methods of health education [
56]. Digital games have the potential to support the learning process, providing greater personalization, dynamism, and autonomy. They are considered promising tools to promote changes in dietary behavior, which is the scope of this study.
Therefore, this study aims to outline a nutritional intervention for school-aged adolescents from the Federal District, Brazil, whose object is a digital game aimed at promoting healthy dietary practices. It is randomized study with intervention and control groups.
Discussion
This randomized study will assess the impact of a nutritional intervention on school-aged adolescents from the Federal District, Brazil. The object is a digital game that was developed specifically for this study. As the literature suggests, mHealth interventions result in high levels of acceptance and improvement of health behaviors [
25,
29,
33]. The study proposal innovates by introducing the concept of an adequate and healthy diet described in the
Dietary Guidelines for the Brazilian Population [
19]. In addition, the game mechanics was inspired in a major worldwide success. According to Bakkes, Tan, & Pisan [
68], a player-centered game design leads to a stronger connection between the player and the technology, ensuring increased playability and satisfaction.
Although this study innovates in terms of design and aims, it also has some limitations, especially because social or environmental factors may interfere with the acceptance of the game [
29]. Therefore, in the process of developing
Rango Cards, a comprehensive experience was designed considering target audience characteristics, autonomy, motivation, and pleasure of learning, which may increase the effectiveness of the intervention in establishing sustainable behavior changes [
62,
69,
70].
This intervention will contribute to the development of specific tools for FNE strategies focused on adolescents, considering that there is still a shortage of educational material for this audience. Thus, this study is expected to become a theoretical and methodological benchmark for other educational initiatives based on the use of digital tools to promote an adequate and healthy diet.