Which diet is better: eating less meat and more fruits, vegetables, and wholegrain products, as recommended by the German Nutrition Society? Should Germany follow the lead of its southern neighbors and consume more fish and seafood? Or even go all-in on a vegan diet? According to a new study from the University of Bonn (Germany), the answer to these questions is not as clear-cut as one might think – depending on which impacts are examined closely. The findings were recently published in the journal Science of the Total Environment.
Every EU citizen consumes 950 kilograms of food and drink per year, which is equivalent to the weight of a small car. Food accounts for one-quarter of all human greenhouse gas emissions worldwide. A significant portion of this is due to livestock farming: Only a small portion of the calories fed to animals is converted into meat. Ruminants also produce methane, which further accelerates global warming.
Furthermore, what we eat has an impact on both our health and the welfare of animals. When comparing diets, these factors should be considered as well. The “One Health” perspective is also used by experts to refer to the optimal health of humans, animals, and the environment. “Studies that apply this perspective to nutrition issues are still rare,” says Juliana Paris of the University of Bonn’s Center for Development Research (ZEF) (Germany).
Several indicators were used by the researchers to estimate the consequences for animal welfare. However, we also used the number of neurons or the size of the brain in relation to the body to estimate the extent to which the respective animals actually suffer when used.
Juliana Paris.
Actual food basket compared with three alternatives
Paris, along with colleagues, conducted an analysis that aims to fill some of this research gap. “To do this, we looked at examples of which products are in people’s food baskets in North Rhine-Westphalia,” she says. “We then compared this reference diet to three different scenarios: a shift based on the German Nutrition Society’s (DGE) recommendations, a shift to a Mediterranean diet with more fish and seafood, and a shift to a vegan diet.”
The foods in each of these three scenarios were chosen to differ as little as possible from the reference diet. “This means that in the Mediterranean version, for example, we increased the proportion of fish and seafood, vegetables, and grain products,” Paris explains. Furthermore, the overall product selection should include the same nutrients in comparable amounts as before. This gave the researchers a food basket for each scenario, which they then analyzed further.
“We relied on various databases to do this,” says Dr. Neus Escobar of the Institute for Applied Systems Analysis in Austria, who oversaw the project. “They allowed us, for example, to estimate the impact of each diet on specific environmental aspects, such as the number of greenhouse gases produced during production or the amount of water consumed. To assess the impact of each diet on health, we used a similar approach.” Red meat, for example, has been linked to an increased risk of certain cancers and heart disease.
Several indicators were used by the researchers to estimate the consequences for animal welfare. These included how many animals die as a result of food consumption and the conditions in which they are kept. “However, we also used the number of neurons or the size of the brain in relation to the body to estimate the extent to which the respective animals actually suffer when used,” Juliana Paris explains.
Fish instead of steak: good for the environment, bad for animal welfare
From the standpoint of One Health, any of the three diets would be beneficial in the long run. However, this comes at the expense of other factors. In many ways, the vegan diet came out on top. However, the production of vegan food necessitates a greater use of water. “In addition, vegans must supplement certain nutrients, such as vitamin B12, vitamin D, and even calcium,” Paris explains.
The Mediterranean diet (while healthy) necessitates more water due to the abundance of nuts and vegetables. Furthermore, if the meat consumed is completely replaced by fish, as assumed in the study, the effects on animal welfare are surprisingly negative: Because fish and seafood are much smaller than, say, cows or pigs, this diet causes far more animals to suffer. Increased honey consumption, which necessitates intensive management of bee colonies, has a negative impact as well. “As a result, it would be advantageous to meet less of your overall protein needs from animal sources,” Neus Escobar emphasizes. “Furthermore, many people today consume far too much fat in their diets. It is possible that reducing the amount of food they eat to what they truly require would have additional positive effects.”
The DGE recommendations, according to the study, are on the right track. However, the other two options are preferable in terms of human health. Nonetheless, the data here show that if you avoid eating meat more often and instead fill your plate with whole grains, vegetables, and fruit, you are not only helping yourself but also the animals and the environment.
