Social marketing-based interventions to promote healthy nutrition behaviors: a systematic review protocol

The growing burden of non-communicable diseases (NCDs) is one of the biggest challenges facing healthcare systems worldwide in the twentyfirst century [1]. NCDs have been identified as major causes of disability and mortality globally. During 2016, about 71.3% of all deaths worldwide were claimed to be due to these diseases [2]. It has been projected that by 2030, NCDs will cause over 75% of all deaths worldwide [3]. Evidence suggests that NCDs are among the main leading causes of death in Iran. According to the latest statistics provided by the World Health Organization, NCDs are responsible for more than 76% of all deaths in Iran. Among these, coronary heart diseases make the most considerable contribution to NCD deaths (by 46%) [4]. The four modifiable behavioral risk factors for NCDs are physical inactivity, unhealthy diet, harmful alcohol use, and tobacco use. It is noteworthy that the NCD-related morbidity and mortality burden due to an unhealthy diet is much more significant than the other three risk factors [5].

During the last four decades, significant changes have taken place in global nutrition patterns. People’s diets have shifted to higher consumption of processed and ultra-processed foods low in nutrients and high in calories [6, 7]. The percentage of foods consumed outside the home, such as fast food, has increased, leading to excessive calorie intake [8]. Besides, there have been significant increases in the consumption of animal-source foods, oils, and caloric sweeteners [9]. In many countries, intakes of sodium, unhealthy fats, and added sugar in the general population are much higher than the recommended amounts [10]. It is important to note that increased consumption of unhealthy foods and beverages has been associated with a lower intake of healthy diet components, including foods with low-energy density and a high content of nutrients such as vegetables, legumes, and whole grains [9]. These dietary shifts have important implications for public health. Unhealthy eating patterns, including high consumption of added sugar, trans fats, and sodium, have been associated with obesity, cardiovascular disease, type 2 diabetes, cancer, high blood pressure, and stroke [11‐13]. Also, such eating patterns have been reported to kill more than 14 million people worldwide each year, equivalent to 40% of deaths due to NCDs [14].

According to the World Health Organization, a healthy diet includes achieving energy balance, limiting energy intake from total fats, replacing saturated fats with unsaturated fats, eliminating trans fatty acids, limiting the intake of free sugars, limiting salt (sodium) consumption from all sources, and increasing consumption of fruits and vegetables, and legumes, whole grains, and nuts [15]. Many efforts have been made to develop nutritional interventions around the world. These primary prevention programs focus on asymptomatic individuals in the general population before an adverse health event occurs [16]. The goal of interventions at this stage is to reduce non-communicable disease risk factors by promoting healthy diets. There are powerful potential interventions that target the factors mentioned above and the cost, access to healthy foods, and individuals’ knowledge. It should be noted that such population interventions, by their nature, should be theoretically useful for all members of society, including those with a history of non-communicable diseases such as cardiovascular disease [17]. However, given the poor quality of the average diet, it is clear that current approaches to improve public nutrition have not been successful and that effective strategies are urgently needed [18].

Health-related behaviors, including nutritional behaviors, are influenced by a wide variety of factors. Understanding the multifactorial nature of these behaviors and the contexts in which they occur is essential for developing effective behavior change interventions. Having a clear theoretical underpinning has been suggested to maximize behavior change interventions [19‐21]. Evidence shows that theory-based interventions effectively influence health-related behaviors than non-theory-based ones [22‐24]. These types of studies provide a framework for developing and evaluating interventions [25]. They also facilitate understanding the factors influencing behavior change and the reasons for an intervention’s success or failure [26, 27]. One of the behavioral theories that is widely used to influence health behavior is social marketing.

There are many definitions of social marketing, but one of the most useful ones describes social marketing as follows: “Social marketing is the application of commercial marketing technologies to analyze, plan, implement, and evaluate programs designed to influence the voluntary behavior of the target audiences to improve their personal and social well-being” [28]. The unique feature of social marketing is that it takes learning from the commercial sector and applies it to induce, encourage, and promote social change entirely, rather than to provide ideas or information [29]. The strengths of social marketing over alternative techniques applied to behavior change include (1) focusing on the consumer—this means that interventions are designed based on the consumers’ wants and needs, not only the priorities of society as a whole [30]; (2) proposing attractive exchanges for the consumer, which makes it possible to change voluntary behavior; in other words, it focuses on convincing not on coercion [31], (3) identifying and appropriately addressing competition to make the recommended products or health behaviors more advantageous than the unhealthy ones [32], and (4) using all the marketing mix components (the basic 4 Ps: product, price, place, and promotion). In social marketing, a product is developed (key benefits, service, or behavior change), the price is evaluated (the costs of stopping an unhealthy behavior or adopting a healthy one, which can be in the form of money, time, opportunity, energy, effort, psychological factors, etc.), the place is defined (the situations in which the target audience can perform the health behavior or obtain any tangible goods or services necessary for the health behavior), and a promotion strategy is planned (selecting promotion techniques and channels) [33], (5) managing programs properly through planning, control, monitoring, implementation, and evaluation [28]. Accordingly, social marketing can be an excellent tool for promoting public health activities.

It is not a new idea to use marketing principles in health education and health promotion to achieve health or social goals [34‐36]. Social marketing has been applied to solve behavioral problems for more than 40 years [37]. There are many examples of effective use of social marketing framework in the field of public health, including promoting healthy eating behaviors [38], prevention and control of AIDS [39], reducing alcohol consumption in youth and adolescents [40], and increasing physical activity [41]. Given the effectiveness of social marketing in changing health behaviors, the present review intends to collect interventional studies that have used the social marketing framework to promote healthy eating behaviors. The objective of this review will be to evaluate the effectiveness of social marketing-based interventions to promote healthy nutrition behaviors.

There is no doubt that diet quality has a major impact on health. A higher-quality diet has always been associated with better health outcomes [64, 65]. The relationship between diet and health is an undeniable cause-and-effect one [66]. This causal relationship has been proven through very detailed studies aimed at identifying causal pathways whereby specific nutrients affect health [67] and the high-quality intervention trials such as those incorporating the Mediterranean diet [68, 69]. Diet is currently among the leading preventable causes of mortality and disability in nearly all countries [70, 71]. Given the role of unhealthy nutrition in increasing the prevalence of non-communicable diseases [72], it is not unreasonable to expect an important step to prevent diseases and reduce mortality rates by correcting eating habits and food choices. However, the critical issue is that it is challenging to implement and maintain health-promoting behaviors, including healthy eating behaviors. This issue is significantly exacerbated in environments where low nutritional value and low-cost ready-to-eat foods are readily available and frequently advertised [73, 74].

Examining the available evidence and modeling based on practical and successful studies is considered the first step to facilitate policy improvement and design effective programs to promote healthy eating behaviors. On the other hand, an essential step for the final judgment on the types of interventions and their impact on promoting healthy eating behaviors is to conduct a systematic review of related studies [75]. Therefore, the present study is intended to collect articles related to interventions based on the social marketing approach to promoting healthy eating behaviors by searching for relevant scientific literature. After the final selection and extraction of papers, the components of the interventions, implementation methods, and their effectiveness will be identified and reported in a systematic review article to guide design interventions with the same purpose.

This systematic review will be restricted to articles in English due to functional reasons, and therefore could miss relevant papers published in other languages.

The review results can provide policymakers with the information needed to make decisions and plan to promote healthy eating behaviors and understand the factors influencing the programs’ implementation.

This review is intended for publication in a peer-reviewed journal. Analyses and scripts will be made publicly available. Any changes to the protocol will be documented as well.