Improving food system sustainability by reducing the environmental footprint of global agriculture while ensuring healthy diets is one of the most pressing global challenges humanity faces in the 21st century and contributes to several of the United Nation’s Sustainable Development Goals (SDGs). Over the last few decades, several dozen publications have addressed this issue, each in its individual way and each with its own scientific merit. The conclusions and recommendations of these — mostly global — studies often suggest changing diets, reducing food waste, or lowering the environmental footprint of agricultural production through increased efficiency. Yet, the sustainability of the global food system has not improved during this time. The big question, and one that mirrors discussions around climate change, is: why is the existing scientific evidence not enough to enable decision makers to take appropriate actions?
There is no single answer to this question. Cautious behavior by individuals and governments, interventions from interests groups, and fear of change are examples of societal, economic, institutional, and structural inertia that prevent change towards sustainability. Yet, one inherent problem in the scientific domain that aggravates the implementation of global analyses into effective policy actions is the often missing contextualization of such assessments. Or in other words: “one size does not fit all”.
This is not at all a novel finding, and this shortcoming still applies to many academic publications. Incentivized by publishers and the scientific community, authors feel the pressure to present apparently groundbreaking and easily communicable implications and recommendations of their studies in order to be published. In contrast, the limitations — such as data aggregation or necessary assumption and/or simplifications — receive much less attention. This becomes a problem when conclusions or recommendations are too broad and lack sufficient context, or when feedbacks and linkages to other domains are not incorporated into the assessment itself. This is especially important as knowledge of such limitations cannot be taken for granted for anyone outside the respective research domain, let alone outside the scientific community.
The recent publication of Springmann and colleagues provides a good example for the issue of missing context. The paper proposes an option space for keeping the global food system within environmental limits (referring to planetary boundaries as introduced by Rockström and colleagues in 2009) while ensuring sustainable and nutritious diets for all. Springmann et al. conducted an extensive and seminal analysis addressing a very timely problem. Yet, their recommendations (discussed in more detail below) for keeping the global food system within environmental limits remain quite general and lack spatial and contextual detail. Resonating the concerns by Fischer, the option space they describe only exists under certain conditions and assumptions, whose realism may be questionable or even non-existent.
Shifting diets — The authors suggest dietary changes towards healthier and more plant-based diets. Yet, dietary shifts are only a viable option for those with sufficient access to diverse, high quality, and nutritious food — and not for the currently undernourished communities depending on animal protein for survival. Beside this ethical component, a related publication by Springmann with a similar team of authors demonstrated that changing diets had beneficial health effects particularly for developed, high- to middle-income countries, while dietary changes in low-income countries, where sufficient access to healthy diets is highly uncertain, had adverse environmental effects due to increased resource use.
Improvements in technology and management — Springmann et al. assumed that closing yield gaps, rebalancing nitrogen and phosphorus fertilizer application, and improving the efficiency of cropping, irrigation, and fertilizer application could improve the global food system’s sustainability. Yet, there are limited opportunities for further intensification through technological advances in industrialised countries dominated by intensively managed food production systems with low yield gaps, while in other countries where yield gaps are high, on-going civil unrest, poverty, and unstable governance hinder yield gap closure. An important aspect that is often not considered, is that even if production were optimized, where can such optimization be easily implemented and where would it actually be most beneficial? Further, the rebalancing of nitrogen and phosphorus fertilizer application from over- to under-applying regions remains a theoretical exercise as it largely depends on equity, allocation, and functioning markets — aspects that are not currently evident in today’s socio-economic setting and render food security a global problem in the first place.
Reductions in food loss and waste — The authors assume that a reduction of 50–75% can alleviate some of the environmental pressures caused by the global food system. Examples of reducing food loss and waste include improved production processes, better storage and transport facilities, more robust crop varieties resistant to pests, and changing consumer habits. Due to the multi-facetted nature of food waste and losses that occur at different stages of the farm-to-plate path, realizing such reductions is highly context- and location-specific, and actually a pretty challenging problem. Further, assuming that reduced food waste will automatically lead to a reduction in the amount of food that needs to be produced — and in turn, a reduced environmental impact — is questionable. The “conserved” food from reduced food waste (mostly from surplus economies in the developed countries) would need to be made available to food-scarce and insecure communities, which — reiterating the issues of equity and imperfect markets — is unlikely under current conditions.
All of the above assumptions that Springmann et al. rely upon for their analysis also strongly depend on resource accessibility (including knowledge, finance, governance, infrastructure, etc.), which is unequally distributed and difficult to establish. For all actions associated with the above measures, there is further the question of mandate, legitimization, and acceptance: for example, who has the authority to introduce a tax on meat (in a developed country) as a top-down measure to spur dietary change? What measures should be prioritized at what scale (local, regional, national, continental, global) if resources are limited? Who should contribute what share to that shift, especially considering the historic debt of industrialized countries in terms of resource and labor exploitation as well as environmental degradation? There are also questions about feedbacks and tradeoffs between the recommended actions. For example, the question arises if improvements gained by making the food system more sustainable will be offset by negative impacts in other sectors such as transport or energy.
The study by Springmann and colleagues is a substantial positive step forward, but to accomplish the “synergistic combination of measures [that] will be needed to sufficiently mitigate the projected increase in environmental pressures”, there are some unexplored questions that remain to be addressed. A diverse set of context specific scenarios and mitigation pathways with local context and at a variety of scales are needed for transforming the global food system, reducing its environmental impacts, and safeguarding food security. Further, inter-societal equity and justice are critical considerations, especially considering the displacement of negative production externalities. Finally, accounting for the uneven needs, development stages, and capabilities of nations is essential to translate global-scale solutions to national action, and to ensure that the global community does not pass the bill to populations who are already politically and economically disadvantaged.
[This blog summarizes discussion outcomes from the LUGE lab centering on the recent paper by Springmann and colleagues. The original version of this blog was published on https://medium.com/the-nature-of-food.]