How Foods of Animal Origin Can Contribute to a Healthy, Sustainable Diet
Photo: Gabriela Brändle,
Agroscope
Foods of animal origin – friend or foe? It all depends on the needs of consumers and on local production conditions, as shown by a major review in which Agroscope took part.
Scientific and political discussions on the role played by foods of animal origin in a healthy and sustainable diet are often polarising. By reappraising the existing data and studies, we aim to highlight the benefits and risks of livestock production for the attention of researchers, policy-makers and society.
High nutritional value of foods of animal origin
An important advantage of foods of animal origin – which include meat, eggs, dairy, fish, molluscs and crustaceans – is their content of readily bioavailable nutrients such as iron, zinc, calcium, vitamin B12, vitamin D, choline, omega-3 fatty acids and essential amino acids. Malnourished populations, for example in sub-Saharan Africa and in South Asia, would benefit from increased consumption of foods of animal origin. So would pregnant and breastfeeding women, infants and young children, adolescents and older people, all of whom have increased nutritional needs.
Health risks of excessive consumption
However, overconsumption of processed meat, red meat and saturated fat can adversely affect health. Where consumption is excessive, there needs to be a focus on moderation. Meat that has been preserved by salting, curing, fermentation, smoking or other processes is particularly problematic. The more a person consumes these foods on average, the higher their risk of developing cardiovascular disease, cancer or diabetes. Consuming excess red meat can also adversely affect health, especially when it is not within the context of a balanced diet; and consuming excess saturated fats, which are present in animal-based foods, especially red meat, increases the risk of cardiovascular disease.
Environmental impacts are strongly dependent on management
It is not just the health ramifications of consuming foods of animal origin but also the environmental impacts that are vehemently discussed in research, policy-making and social circles. We examine five spheres in detail: land use, climate change, soil, water, and biodiversity. There are positive as well as negative environmental impacts in each of these spheres.
Sphere | Positive Impact | Negative Impact |
Land use | With the help of ruminants, 1.38 billion ha of land that is unsuitable for arable farming is used for food production. | 0.7 of the 2 billion ha of grassland currently used for livestock farming could also be used for arable production (though with potential loss of ecosystem services such as carbon storage, erosion protection or biodiversity through conversion). In addition, 0.55 billion ha of arable land – 40% of the world’s farmland – is currently used to grow animal feed. |
Soil | In the right amounts, animal manure provides plants with nitrogen and phosphorus and increases organic matter in the soil. This promotes soil fertility as well as water-retention capacity. | Excessive inputs of manure and slurry lead to nutrient losses through gas emissions, leaching and run-off. |
Climate Change | Adapted grazing and fertilisation increase organic matter in the soil, thus allowing additional carbon to be bound in the soil. Greenhouse gas emissions, especially methane, can be reduced if animal and plant systems are better integrated and animals become more efficient. | Livestock farming and feed production emit greenhouse gases, including methane and nitrous oxide. |
Water | Locally adapted animal husbandry favours infiltration, as well as water quality and volume. | High water consumption in systems using irrigation and endangerment of freshwater sources through run-off as well as nutrient loss from intensive livestock farming. |
Biodiversity | The long history of livestock husbandry in Europe has led to extremely biodiverse ecosystem types, which can be preserved through adapted grazing management. | Overfertilization and pollutants from livestock farming endanger biodiversity. |
Enhancing positive impacts via circularity
The Food and Agriculture Organization of the UN, the FAO, has identified three main strategies for countering the negative impacts of livestock farming on climate change:
- Improve the efficiency and productivity of livestock farming.
- Integrate ruminants into the closed-loop management system.
- Increase soil carbon content through adapted grazing.
Priority is placed on the circularity strategy to enhance positive interactions between animal husbandry and the environment. For this, the large-scale, specialised plant- and animal-production sectors must be linked with one another via the trade in farmyard manure and animal feed. This means, for example, a higher proportion of grass and food-production residues in the feed ration of ruminants and the use of farmyard manures for fertilisation and power generation.
Considering the local context and including those affected
Thus, if we are to bring about sustainable and positive changes in the production and consumption of foods of animal origin, we should consider the local context with its corresponding dietary and environmental conditions, and include the interest groups affected by the changes.
Conclusions
- Animal- and plant-based foods have complementary nutritional profiles. A balanced diet containing both of these food groups lowers the risk of nutrient deficits.
- Population groups that consume large quantities of meat, particularly processed meat, would in general benefit from a lower consumption. This could also have environmental benefits.
- Production of foods of animal origin can have negative environmental impacts in terms of land use, climate change, soil health, water volume and quality, and biodiversity. In all these spheres they can also have positive impacts that can be enhanced by using best practices.
- Linking animal and plant production within the context of circular management can conserve resources and reduce negative environmental impacts.
Bibliographical reference
How Foods of Animal Origin Can Contribute to a Healthy, Sustainable Diet