A recent study published in the Proceedings of the National Academy of Sciences (PNAS) Journal discussed the perspectives to attain healthy and sustainable diets.
Study: Toward healthy and sustainable diets for the 21st century: Importance of sociocultural and economic considerations. Image Credit: Okrasiuk/Shutterstock.com
Attaining equitable, healthy, and sustainable diets is a defining challenge for food systems. The EAT-Lancet report underscored the importance of dietary shifts required to remain within planetary boundaries.
Besides, it is necessary to understand the feasibility of changes needed at agricultural, sociocultural, and economic levels. In the present study, the authors discussed the various perspectives to achieve sustainable and healthy diets within geographical and sociocultural subtypes of the food system.
Diets in different contexts
Evidence shows that higher consumption of processed or red meat elevates the risk of non-communicable diseases (NCDs) and premature death. Studies thus support the benefits of minimally processed plant-based foods, such as vegetables, fruits, seeds, legumes, whole grains, and nuts.
The highly palatable ultra-processed foods and drinks provide increased quantities of saturated fat, energy, sugar, salt, and additives associated with NCDs and obesity.
Plant-based foods have the least impact on greenhouse gas emissions, while animal-based foods have the highest. The proportion of starchy staples and the disposable income spent on food declines with rising income.
Low socioeconomic groups have limited physical and financial access to high-quality food, preventing food choices. Further, in low and middle-income countries (LMICs), there is a trend to substitute plant-based protein with animal-based proteins, while opposite directions have emerged in some high-income countries (HICs).
Diets and food systems
Sustainable diets are associated with sustainable food systems per se. Shifts in technology, dietary changes, or production alone will be inadequate to attain levels within planetary boundaries. Food shops and retail influence food choices, eating culture, and nutritional habits, while agriculture and food companies shape the food supply.
A sustainable food system will support healthy lives for generations while being economically efficient and ecologically resilient. Further, no single global food system or diet exists, but multiple individual diets and local food systems exist. Food system actors and scientists should focus on the broader food environment governing availability, affordability, and access.
Moreover, food system actors' behaviors at different levels are governed by economic principles. For instance, individual households at the micro level buy available, accessible, and affordable foods, contributing to national disparities.
Economic principles at the macro level match food demands to global or regional production, contributing to environmental problems.
Eating habits at the micro level stem from the situational interplay between the four dimensions – culture, economy, health, and environment. Economic and cultural norms at the macro level can be modified to support sustainable diets. Food system policies and research require reliable indicators and metrics to characterize sustainable diets.
Developing universal indicators of nutrients, energy, and other components into a diet quality score has been challenging. Environmental indicators, including water and land use, are commonly used, but water scarcity, biodiversity loss, and land-use change can better reflect the time span of reaching planetary boundaries.
Nutrition research has long relied on mathematical models for optimizing dietary patterns. These models integrate foods into diets to fulfill desired criteria.
Nevertheless, most models combine foods as independent entities and have difficulties accounting for the cultural diversity of dietary patterns. Other approaches overcome this by considering a priori-defined vegan, vegetarian, or omnivorous diet.
Food system actors and accountability
An economic and cultural reset is necessary beyond the short-term interests to efficiently and economically serve sustainable diets to 9-10 billion people. Younger generations are concerned about the future of the planet.
Citizens have been taking responsibility by engaging in local policies. Meanwhile, non-governmental organizations have been involved in issues like fair trade, animal well-being, and investments in fossil fuels.
Others have been involved in organic, sustainable co-operative farming, while consumer protection and advocacy groups have sued governments for failing to adhere to greenhouse gas emission targets. Thus, while national actors hesitate to introduce necessary changes in the system, civil society has expressed dissatisfaction with the status quo.
Food-based dietary guidelines are an established way for governments to incorporate sustainability into the national context.
Long-standing efforts to promote healthy eating have revealed that information-driven strategies are ineffective, as only some people adhere to or have knowledge of nutritional recommendations. Agricultural policies should switch to subsidizing sustainable production networks.
Citizen concerns, government policies, and intentions of food companies cannot achieve a systemic change. The national-level disparities indicate a power imbalance between governments, local companies, and local communities. Despite the limited power, citizens try to hold private and public actors accountable for strategies that can make a difference.
While most foods in the global supply chain are produced locally by small and medium enterprises, a few large seed companies, transnational food corporations, and international commodity traders have gained influential positions in the food system.
Therefore, governments should counterbalance this with taxes, subsidies, and trade agreements, incorporating the value of health, biodiversity, and ecological impacts.
Food system transition depends on the local implementation of global targets. Research on food systems should consider the local nature of the four dimensions and the accountability of actors at different levels.
The local context is pivotal because diets are inherently personal and local. There is a need for a systems approach to sustainable diets beyond the consumers' span of control.
Food system actors are responsible for the transition, given their position and influence at decisive points in supply chains.
Overall, changes in global food systems warrant local, national, and international solutions and a new balance between public and economic interests to strengthen the regulatory power of food system actors and increase corporate accountability.