Drivers and barriers for adopting healthy and sustainable food swaps in young adults
Project Lead
Challenges
There is a need for dietary shifts to make the transformation towards diets that are healthier and more environmentally sustainable. In the past 50 years, we have seen a shift towards unhealthy diets high in calories, and heavily processed and animal source foods. Transitions to unhealthy diets are increasing the burden of obesity and diet-related non-communicable diseases and are contributing to environmental degradation. Dietary guidelines are an important behaviour change policy tool to guide consumers in terms of the foods and diets they should be eating. However, healthy diets alone do not produce substantial reductions in greenhouse gas emissions. Therefore, dietary guidelines need to include recommendations for environmental sustainability.
A few countries have started to produce dietary recommendations for health and environmental impacts. In addition, dietary guidelines in most countries fail to take account of reasons behind peoples’ food choices, such as habits, preferences, affordability, circumstance, culture, and social norms. Another issue with the implementation of nutrient-based dietary guidelines is that people eat foods, not nutrients. Foods contain multiple nutrients that cannot be readily swapped for one another. Therefore, more food-based interventions are necessary for effective behaviour change strategies towards more healthy and sustainable dietary patterns.
Evidence on existing interventions
Food purchasing is a key determinant of food consumption, and interventions targeting the nutritional and environmental quality of food prior to or during shopping presents a clear opportunity for effective behaviour change. Individual-level interventions previously identified as effective behaviour change techniques include tailored dietary advice, information, self-monitoring, and personalised feedback. Interventions implemented in grocery stores, particularly those that manipulate price, suggest that swaps, and perhaps manipulating item availability, have an impact on purchasing and could play a role in public health strategies to improve health. Using swaps to promote health would be a scalable and low-cost intervention, but currently there is limited evidence on its effectiveness. The success of offering swaps depends on consumers accepting the suggested swaps, but most studies thus far did not explore why swap acceptance rates could be low. Acceptance could be low due to how swaps were framed, perceived to restrict freedom and personal autonomy, and perceived to be less palatable. Also, many consumers put lower importance on health messages and higher importance on taste and price. Indeed, product costs have been a particularly crucial factor for those on lower incomes, and lower price can encourage choices of healthier products more effectively than health status labels.
The development of behaviour change interventions requires an understanding of facilitators and barriers for consumers to make food choices that are healthier and more environmentally sustainable, but also economically affordable. Currently we know relatively little about how individuals interact with their food environment and apply their perceived knowledge of healthy and sustainable diets. Several factors including socio-economic, life-stage, demographic, and geographic background, can drive individual decisions and behaviours when selecting foods and drinks, indicating that behaviour change interventions require a more in-depth understanding of drivers of individual food choice, on a more granular level.
Questions
- What behaviour change interventions can influence consumers to make long-term changes with respect to their diet and food safety and that reduce or minimise health inequalities?
Solutions
The project aims to identify facilitators and barriers for adopting, and adhering to, recommended personalised food swaps that aim to reduce the intake of red meat and replace this with fish or plant-based foods, in young adults. We also assess the effectiveness of adopting healthy and sustainable food swaps to improve general markers of health in Scottish young adults.
This project is identifying the most frequently issued food swaps, and facilitators and barriers to adopt such swaps, to increase our understanding of consumer attitudes towards shifting to healthier and more sustainable diets in our study population on a food and drink level. In the analysis, we include and consider important socio-economic factors, like access and affordability, and motivation for dietary change. This work provides evidence-based recommendations for policy that will improve access to healthy and sustainable diets for different Scottish population groups, including the reconsideration of some of our dietary guidelines.
The overall expected output of this project is a fully operating, validated and user-friendly Food Swap tool that is implemented on a wider scale, either in research settings or in public health settings. The Food Swap is being applied in the human intervention study and tested during food events and public health meetings to collect customer feedback on the tool itself and its messaging.
Project Partners
Progress
In the past year, we analysed red meat consumption in young adults in Scotland. Consuming less of the most environmentally damaging foods (meat and dairy) is one of the most effective methods to reduce food-related greenhouse gas emissions. In 2020, the UK Committee on Climate Change (CCC) advised that consumption of all meat and dairy should fall by at least 20% by 2030, and that consumption of all meat should fall by at least 35% by 2050, to significantly reduce our food system-based carbon footprint. In 2023, the Scottish Government partially accepted this recommendation.
Meat consumption in the UK and in Scotland is high, especially in the age group 18-30 years. In this age group, the majority eats red meat (either fresh or processed) on 3 or 4 days out of the 4 measured in the National Diet and Nutrition survey, with an average intake of 102 grams of red meat per day. Research on substitution choices when individuals reduce their meat or dairy intake is limited. Consumption of red and processed meat has been declining in the past 10 years, coupled with an increase in white meat consumption but no increase in fish consumption. Plant-based alternatives are also becoming more popular in the UK.
Based on these new data we decided to monitor patterns in red meat consumption behaviour in young adults before, during and after a food swap intervention that provides personalised food swaps to:
i) reduce individual intake of red meat (including beef, veal, lamb, and pork), by 20% (following the recommendation of the Climate Change Committee, but targeting the consumption of red meat rather than total meat), or
ii) reduce the individual intake of red meat to <60 grams per day, or 420 grams per week (following SACN advice, but taking into account that the average per capita intake of red and processed meat has come down from 70 grams per day 10 years ago)
Our target population is young adults, not only because of their relatively high intake of red meat, but also since young adulthood is one of the most dynamic and complex transition periods in life. Youth is a crucial period where values, behaviours and habits are malleable, and when well-timed, an intervention may produce long-term benefits. Furthermore, our research as part of B7 (“Climate change, biodiversity and changing diets”) has shown that this age group is the most relevant determinant of the readiness-to-change towards a more sustainable diet, with those in the younger age groups being more ready to change.
In the past year we developed a customised Food Swap tool to identify personalised food swaps, which will be used as part of the intervention in the human study. The Food Swap tool is a technical infrastructure/web interface developed in the R shiny app that links Intake24, where participants can record their diets, to a web interface where participants receive their food swap recommendations. These food swap recommendations are produced by a linear programming tool that optimises the nutritional quality of a list of foods consumed over 4 days against UK dietary targets, using constraints that minimise greenhouse gas emissions and cost, as well as constraints to reduce the intake of red meat coupled with increasing the intake of fish and plant-based alternatives. The tool will offer a range of food swaps, and participants can accept or decline these food swaps.
The protocol for the human intervention has now been developed and is in the final stages of ethical review.
Related Projects
Sustainability of Healthy Diets: There is no single healthy, sustainable diet, since there are many different ways of achieving the dual dietary goals for health and environmental sustainability, and dietary intakes and the types of food chosen differ across different populations. This adds to the complexity of assessing and translating dietary advice to consumers. The research in this RD will...
- Diet & Food Safety
- Human Nutrition
- 2016-2022