The food we consume has a direct effect on our ecological environment. For instance, in 2015, it was estimated that the food industry alone was responsible for 34% of greenhouse gas emissions into the atmosphere.
However, the environmental consequences of food production go beyond global warming. Food production involves additional consequences, including depletion of freshwater resources, land and water pollution, and a loss of biodiversity due to extensive agricultural practices—all of which harm our environment.
As the global population continues to grow, protecting the environment becomes critical for ensuring long-term human existence. Some nations have already implemented measures to minimize the food industry's ecological footprint.
These include reducing food waste, which accounts for one-third of all food produced spoiling or being discarded before reaching consumers; enhancing existing production technologies to increase agricultural yield without expanding land use; optimizing crop irrigation and fertilization practices, and recycling water and fertilizers. In the livestock sector, modifying animal diets and feeding practices can lower the environmental impact and reduce greenhouse gas emissions.
Changes in consumption habits
A model developed by researchers from several universities demonstrated that while technological improvements, increased food production efficiency, and waste reduction can significantly mitigate the expected environmental damage by 2050, these measures alone will not suffice. O
nly a change in food consumption habits, alongside these strategies, will allow us to maintain an environment where human life is safe and not existentially threatened by Earth's instability. In fact, the model highlights that a global dietary shift, specifically adopting a diet that includes as little animal-based food as possible, known as a flexitarian diet, is expected to lead to the most substantial decrease in greenhouse gas emissions compared to other interventions.
So, which diet has the least environmental impact? Evidence suggests that plant-based diets are less harmful to the environment than animal-based diets. This is due to direct factors, such as methane emissions from ruminant livestock, and indirect factors, such as the resources required to cultivate crops for animal feed.
Previous studies have created several models to examine the ecological impacts of different dietary patterns, finding that vegetarian and vegan diets reduce greenhouse gas emissions, land use, and freshwater consumption compared to meat-inclusive diets.
However, these studies use models that do not fully reflect reality, as they rely on averages rather than actual food consumption patterns and do not specifically examine the ecological consequences of food products based on how and where they are grown.
To reliably assess the environmental impact of food consumption, particularly when comparing meat-based diets with vegetarian or vegan diets, it is crucial to use data on real consumption patterns as well as consider additional factors such as the food's production location and method, to quantify the environmental impact of each food product.
What do we eat today?
In a study published in the journal Nature, researchers examined the relationship between the eating and drinking patterns of 55,000 UK residents and five environmental indicators: greenhouse gas emissions, freshwater use, marine pollution, land use, and impact on biodiversity.
The eating patterns data was collected in a previous study that tracked participants' dietary habits over two decades to explore the link between diet and cancer. Participants were classified into one of six groups based on their self-reported consumption: vegans, vegetarians, fish-eaters, low meat-eaters (less than 50 grams per day), moderate meat-eaters (50 to 100 grams per day), and high meat-eaters (more than 100 grams per day).
The researchers linked the eating patterns to a database summarizing the environmental impacts of approximately 57,000 different food items. This database is unique because it includes data on factors such as the growing method and location, which influence the environmental impact of food.
For instance, carrots grown in a greenhouse in Spain have a different environmental impact compared to those grown in a field in England. The database's scope is also unique: it encompasses information from 570 studies, covering 38,000 farms across 119 countries on five continents. This broad scope allows researchers to more clearly determine whether different dietary patterns affect the environment.
The researchers found that diets containing animal-based components, such as meat and cheese, have a greater environmental impact than plant-based diets. Low meat-eaters had about 30% less environmental impact than high meat-eaters, while vegans' impact on greenhouse gas emissions was only 25% of that of meat-eaters.
This dramatic difference is due to livestock requiring more land than crops; driving increased deforestation. Reduced tree cover decreases the amount of carbon dioxide that trees can store and utilize. Furthermore, land dedicated to growing feed for animals not only fails to directly benefit humans but also demands substantial amounts of fertilizer, frequently derived from fossil fuels, thus contributing to higher carbon emissions.
The dietary impact on the ecological system, as mentioned, is not limited to greenhouse gas emissions. The study found that a vegan diet also benefits the environment by using less land (25% of a meat-rich diet’s impact), consuming less freshwater (46% of that used by a meat-rich diet), producing less marine pollution (27%), and being less harmful to biodiversity (34%).
Quantity matters too
Not everyone can choose vegetarianism or veganism, but the amount of meat consumed also significantly impacts the environment. The study found that those who eat small amounts of meat are responsible for about 70% of the environmental consequences of high meat eaters. Thus, there is no need to be vegan or even vegetarian to reduce harmful effects on the planet—it’s enough to consume less animal-based food.
Ultimately, our dietary choices depend on us. This study highlights the substantial impact of the food industry on the environment and global health, an impact we can genuinely reduce through more moderate consumption of animal-based foods and greater emphasis on plant-based options. Most importantly, the food we eat should be tasty, nutritious, and satisfying.