Food systems account for one-third of global greenhouse gas emissions. If left unchecked, these emissions will likely cause enough additional warming to push the world’s average temperature above a 1.5°C increase by the 2060s.
Research now adds air pollution to the list of problems caused by agriculture. Livestock farming, in particular, is a major source of ammonia emissions. These emissions react with other pollutants to form fine particulate matter, which can cause health problems such as cardiovascular disease, lung cancer, and diabetes.
A recent study published in Nature Communications found that switching from current diets to healthier, more plant-based ones could prevent up to 236,000 premature deaths worldwide by improving air quality alone and could increase global GDP.
Healthier diets, cleaner air
According to the World Health Organization, 4 million premature deaths were linked to outdoor air pollution in 2019. Agriculture is responsible for about one-fifth of these deaths.
We examined what would happen to air quality if people around the world shifted toward healthier and more environmentally friendly diets. This includes flexible diets with less meat, vegetarian diets without meat, and vegan diets without animal products.
Our results show that switching to plant-based diets could significantly reduce air pollution. In regions with large numbers of animals, such as Belgium, the Netherlands, northern Italy, southern China, and the midwestern United States (where there are eight pigs per person in Iowa), particularly significant reductions in fine particulate matter concentrations would be seen.
Better air quality leads to better health. We found that adopting flexible diets could prevent over 100,000 premature deaths worldwide. The health gains from cleaner air contribute to the benefits of a more balanced diet.
As people consume fewer animal products, these health benefits increase. For example, if everyone were vegan, the number of premature deaths from air pollution could be reduced by more than 200,000. Adopting a vegan diet in Europe and North America could reduce premature deaths from air pollution by approximately 20%.
Clean air is an often overlooked but important aspect of the working environment. Studies have shown that air pollution reduces the productivity of workers in many different jobs, from farms to factories. For example, research has shown that air pollution affects the productivity of blueberry pickers and pear packers.
Enabling change
Improving air quality undoubtedly benefits our health and economy. We therefore advocate that dietary changes be firmly placed on the policy agenda.
Adopting a more plant-based diet is a cost-effective strategy for tackling emissions. But it also reduces the need for expensive investments in emission-reducing equipment for livestock systems, such as scrubbers that clean ammonia from the air.
Eating less meat will also reduce the need for stricter measures to reduce pollution. For example, researchers have previously suggested relocating 10 billion animals from southern and eastern China to reduce ammonia exposure for people in these regions.
Transitioning to a healthier, plant-based diet offers a wide range of benefits beyond cleaner air. These benefits include reduced risk of diet-related diseases, lower greenhouse gas emissions, and reduced use of land, water, and fertilizers for agriculture.
If we rely solely on technological solutions, it will be difficult to achieve ambitious progress in all these areas at the same time.
In the summer of 2023, German supermarket chain Penny conducted a week-long experiment to raise awareness about the true cost of food products on human health and the environment. The prices charged to customers took into account the impact of food products on land, water use, health, and climate.
This concept can be applied more broadly. However, to make this policy fair and acceptable, it needs to be combined with ways of using tax revenues to ensure that consumers are not worse off, such as reducing and protecting the VAT applied to fruit and vegetable products and compensating vulnerable households. This will keep overall food spending under control and protect low-income households.
https://phys.org/news/2024-01-plant-based-diets-cleaner-air-world.html
