Diet and nutrition are major determinants of population health. Promoting a healthy diet is, therefore, one of the key strategies in the primary prevention of noncommunicable diseases like cardiovascular diseases, diabetes, cancer, and obesity (WHO, 2013). These diseases are strongly socially patterned, disproportionately affecting individuals with a lower socioeconomic position (SEP). Also with regards to diet and nutrition, there is abundant evidence that diet quality follows a socioeconomic gradient, with people with a lower SEP showing unhealthier diets consisting of higher sugar, salt and saturated fat intake, and less vegetables, fruits and nuts (Ball, 2015; Psaltopoulou et al., 2017; van Rossum et al., 2020). The drivers of this SEP gradient in diet quality are multiple, diverse, and dynamic, ranging from physiological factors to aspects of the physical, economic, sociocultural and political environment (cf. Darmon & Drewnowski, 2015). There is, however, general consensus that individuals experiencing socioeconomic disadvantage are an important group whose dietary health could benefit from well-developed interventions that tackle their specific needs and barriers.
Diverse issues including health literacy, family and work commitments, costs, and social influences have been identified as barriers and facilitators to the implementation of dietary interventions among those with lower SEP (Bukman et al., 2014; Coupe, Cotterill, & Peters, 2018; van der Heijden, te Molder, Jager, & Mulder, 2021). It appears to be difficult for health professionals to effectively target and engage individuals from this target group in their interventions (Everson-Hock et al., 2013). Individuals with low SEP are less likely both to perceive the need for diet-related advice, and to participate in these interventions than those with a higher SEP (Bayley et al., 2018; Lakerveld et al., 2008; Schneider, Schulz, Pouwels, de Vries, & van Osch, 2013). Furthermore, those with lower SEP are more likely to drop out after initial participation in interventions (Hadžiabdić et al., 2015; Roumen et al., 2011). Finally, there is evidence that socioeconomically disadvantaged individuals may experience poorer behaviour change outcomes than those with higher SEP, potentially leading to further intervention-generated inequalities (Bull et al., 2018; Michie, Jochelson, Markham, & Bridle, 2009; White, Adams, & Heywood, 2009). This may partly be explained by differences between social classes in food and nutrition-related attitudes, beliefs, social norms, and knowledge (Ball, 2015; Darmon & Drewnowski, 2015; Mackenbach et al., 2019; Marcone, Madan, & Grodzinski, 2020). Apparently, different approaches are necessary to successfully reach and help disadvantaged individuals and achieve better behaviour change outcomes in diet-related interventions.
Digital innovations, such as e-health and m-health, have facilitated the development of tailored approaches and reaching large populations against relatively low cost per person (Stanczyk et al., 2014). E-health applications can be designed to modify people’s attitudes and behaviours, and to increase their belief of being able to change the behaviour (Springvloet et al., 2015a). They offer great opportunities to adapt interventions to the needs of disadvantaged people by the presentation of bite-sized information in plain language, accompanied by reading functions, appealing visuals and animations, and speech recognition (Kim & Xie, 2017). These features can be used to apply a wide array of behaviour change techniques (BCTs), such as providing information, facilitating goal setting, increasing social support and prompting barrier identification; techniques that may be particularly helpful for low income groups (Ball, 2015). Again, however, it is observed that disadvantaged individuals are less likely to use e-health interventions for health promotion and self-management of dietary behaviour (Latulippe, Hamel, & Giroux, 2017; Reiners, Sturm, Bouw, & Wouters, 2019; Schneider et al., 2013). Moreover, evidence as to which BCTs are a good fit for populations with a low SEP is scarce (Bull et al., 2018; Michie et al., 2009), particularly in the field of dietary e-health interventions.
The aim of our scoping review, therefore, is to identify the BCTs that are used in dietary e-health interventions specifically targeted at individuals with a low SEP. Our review focuses on the techniques applied in the interventions, using Michie et al’s taxonomy of behaviour change techniques, which includes 93 BCTs which are categorised in 16 clusters (Michie et al., 2013). In our review, we include studies that examined e-health interventions aimed to change eating behaviour of people with a lower SEP, or comparing people from different SEP groups. We aim to answer the following questions:
1) Which BCTs are applied in e-health interventions aimed at eating behaviour of people with a lower socioeconomic position?
2) Which of these BCTs coincide with improved eating behaviour among people with a lower socioeconomic position?
[1] For reasons of conciseness, we use the term e-health to indicate both e-health and m-health from this point onwards.