Food-related greenhouse gas emissions from land use changes, waste management, agricultural production, product packaging, etc. account for more than a third of the emissions that can be traced back to human activities, according to the UN.

At the same time, according to the UN, the world population will grow to around 10 billion people in the next 30 years. Supplying an additional 2 billion people with food compared to today means a huge global challenge - also because climate change has an impact on agricultural production.

There is also a resource problem: At the beginning of December 2021, the UN's Agriculture and Food Organization (FAO) warned that «the foundations of our agricultural and food systems - soils, land and water - were already at their «breaking point»».

A «planetary health diet» ...

So when we talk about «healthy and sustainable nutrition», the health of the planet that our nutrition needs to provide for has to be taken into account as well.

In 2019, a team of 37 specialists from the fields of nutrition, ecology, agriculture and political science dealt with the question of how sustainable and healthy nutrition can be achieved on a global level, taking these factors into account. In their 40-page study, the members of the EAT Lancet Commission outlined a general diet for the entire world. According to their model, a daily plate of 2500 kcal on average would consist of the following foods:

• 300 g vegetables
• 250 g dairy products
• 232 g whole grains
• 200 g of fruit
• 125 g pulses and nuts
• 84 g animal protein (meat, fish, egg)
• 50 g tubers and starchy foods
• 50 g added fats (mainly unsaturated oils)
• 0 g added sugar, replaced by sweeteners (31 g)

According to the authors, this change in diet would prevent around eleven million premature deaths annually, «which corresponds to between 19 percent and 24 percent of the total number of deaths in adults.»

According to the «SonntagsZeitung» newspaper, «climatarians» are also focusing on these considerations. The concept: Above all, we must eat what is healthy for the planet. Less animal products such as red meat, sugar or refined grains. Instead, more vegetables, fruits, nuts or fish. A gratifying by-product of this diet is that it is healthy for the planet as well as the human body. According to the EAT Lancet Report, the consumption of fruits, nuts, and vegetables must double by 2050, while the consumption of red meat and sugar must be more than halved.

However, this approach is also associated with conflicting goals. The production of significantly more plant-based food requires huge additional agricultural land and resources such as water. So that primeval forests and biodiversity can be protected, the existing areas must therefore be managed as efficiently as possible. Preserving fertile land and restoring degraded soils are essential. But those who want more plant-based products such as fruits and vegetables on the «world plate» also depend on the appropriate tools for cultivation. This also includes digital solutions, all forms of crop protection, new fertilizers, and modern breeding methods such as genome editing. Climate change will alter the cultivation of crops throughout the world and make it more difficult in many places. If farmers are to produce more under these conditions, they will need the full range of tools available. Nutritional systems are additionally based on laboratory-derived solutions such as micronutrients and alternative proteins such as seaweed, insects or cultivated meat. In brief: Innovative technologies are essential.

Livestock farming must also be viewed in a differentiated manner. For climatic reasons, reducing meat consumption may seem to make sense. But in many regions of the world, livestock is the only sensible use of land. This is especially true for Switzerland, where a large share of the pastures is in the Alps and is not suitable for cultivation. In other parts of the world, animal products such as meat are virtually the only sources of protein for humans. In dry regions in particular, keeping sheep or goats as frugal protein and milk suppliers makes sense. In an urban context, it is often chickens that provide humans with important proteins. In light of this, a blanket «animal keeping ban» does not make much sense.

... in contrast to the current nutritional reality

The «ideal diet» outlined above contrasts with current consumption habits, the differences between which can be illustrated as follows:

• In North America, meat and dairy intake account for 288 percent and 253 percent of the global diet, respectively;
• In sub-Saharan Africa, current consumption of starches is 729 percent of the intake recommended by researchers. These foods make up three quarters of the diet.

For its part, the EAT Lancet Commission emphasizes in the preamble of their synthesis report: «There is still no global consensus on what constitutes a healthy diet and sustainable food production and whether a «planetary health diet» may be achieved for a global population of 10 billion people by 2050.»

Switzerland also faces challenges

In Switzerland, too, the agricultural and food sector is responsible for close to 30 percent of greenhouse gas emissions. Two thirds of the ecological footprint of Swiss food consumption is generated abroad - through the import of food, feed and raw materials.

In order to reduce the footprint on our plate, we have to know the starting point. This is exactly what a team within the framework of the Swiss National Fund program «NRP 69 Healthy Eating and Sustainable Food Production» has evaluated. This National Fund project looked into the question of how healthy eating can be promoted in Switzerland. Under what conditions can high-quality and safe food be offered in sufficient quantities and at affordable prices, with the most efficient use of resources and low environmental impact? The project ran for five years. The results of the 26 individual research projects can be accessed here.

One of the research projects measured the carbon footprint of nutritional practices caused by the first national nutrition survey «menuCH». This part of NRP 69 came to the conclusion: «The Swiss eating habits were between 1.1 and 2.6 metric tons CO2eq/person/year* (corresponds to a vegetarian and meat-based diet, respectively). That is higher than the federal recommendation of 0.6 metric tons of CO2eq/person/year for all consumption categories.»

Marlyne Sahakian, Assistant Professor of Sociology at the University of Geneva, coordinated this particular research team. She comments on the results as follows: «Since even veganism leads to emissions of more than one metric ton of CO2 equivalent per year, we have to rethink the problem on a different scale and change the system of food supply.»

However, these results remain an estimate. It is almost impossible to define the carbon footprint of a food plate or the diet of a household over a certain period of time, because the variables are so numerous and the traceability of the transport routes is difficult in a globalized society.

Taking a comprehensive look at sustainable nutrition

Sustainable nutrition cannot be reduced to a carbon footprint. This is also shown by the further results of NRP 69, although these are also incomplete and equate sustainability above all with «environmental friendliness».

The authors of the book «Une écologie de l'alimentation» of the «Unesco Chairs World Food System» take a more holistic view. They remind you that sustainability is usually understood to mean the pursuit of social justice, the creation of human well-being (often represented as an economic dimension) and the preservation of the ecological integrity of resources, to which a time dimension is added: «Today's sustainability cannot be allowed to be achieved at the expense of tomorrow». The authors have hit a nerve with this: First and foremost, we need a common understanding that sustainability has three pillars and a time dimension. However, they also come to the important conclusion that one of the decisive challenges in the transformation of the food system is to include different social and cultural groups in the dialogue. It must not be allowed to happen that people who cannot afford a balanced and sustainable diet are forgotten and do not have their voices heard. They must struggle with challenges other than the discussion about «proper nutrition».

Individual responsibility vs. public policy

Therefore, responsibility for a healthy and sustainable diet cannot fall on consumers alone. Especially not when consumers live with very limited resources, emphasizes Lorana Vincent, national coordinator of the French association Vrac. In the last edition of the French magazine «Sésame», she emphasized that «Sustainable nutrition must not be a question for the individual, which often amounts to an appeal to responsibility and virtue. Such appeals cannot be heard by people whose nutritional situation is precarious. Nutrition must be a political question».

In fact, the discussion about healthy and sustainable nutrition tends to take place in the more affluent spheres of Western societies. At the same time, according to FAO 2020, between 720 and 811 million people worldwide still suffer from hunger. Moreover, the high costs of a healthy diet combined with the persistently large income inequality mean healthy nutrition unattainable for around 3 billion people in all regions of the world in 2019. In addition to the comprehensive concept of sustainability, the debate also requires the understanding that «resources» do not just mean natural resources, but also work, energy and finances. A healthy and sustainable diet must be affordable for poorer people as well.

Nicolas Bricas, socio-economist at the Centre de coopération internationale en recherche agronomique pour le développement (Cirad) and holder of the Unesco Chair for World Food, summarized the problem as follows for Sésame: «There is a discrepancy between those who advocate for a restriction for environmental, health or ethical reasons and those who do not understand that this choice is being forced upon them. However, there is no real discussion about these issues, no quiet exchange between the various interest groups, although we need a real social blueprint for our production and consumption patterns.»

An agricultural policy alone is not enough

In June 2020, the working group of NRP 69 «Healthy Eating and Sustainable Food Production» came to a similar conclusion for Switzerland after five years of research. Their report addresses the federal government: «A healthy diet and sustainable food production cannot result from isolated measures within the food system.» According to the researchers, public health, food and agriculture policies, which are currently three independent domains, should be coordinated in a systemic framework aimed at ensuring a healthy and sustainable food system for the benefit of the population. We hope that politicians will hear this call for a holistic view when they will be deciding on a new version of the agricultural policy in the near future. Resource efficiency in the broadest sense must be considered. The Council of States has also asked the Federal Council to present a report on the entire food system as a basis for further discussion.

«Heidi.news» draws the following conclusion: The perfect food plate or the perfect diet that does justice to both human health and sustainability in all its dimensions (social, economic and ecological) does not really exist (not yet?) and is only part of a huge puzzle.