Any person with a plant-based diet will surely jump into a lengthy ramble when you ask them what they like about it. Being plant based has many benefits, including a lower impact on health and the environment than animal based diets. But are plant based diets really that much better for the environment than omnivorous diets, as your local vegan claims? What about grass-fed meat? Is fish better for the environment than meat? What if you’re vegetarian? Does that mean anything? In this post, I hope to clarify the environmental impact of plant and animal based diets, while investigating what food groups are the most sustainable.
For this post, I will define sustainable diets as “those diets which are protective and respectful of biodiversity and ecosystems, culturally acceptable, safe and healthy… while optimizing natural and human resources.” Environmental sustainability includes efficiency of the food and it’s production, compared with its environmental impact.
First, there are many factors that play into the environmental impact of food, such as the cultivation method, raw materials processed, manufacturing, packaging, transport, distribution, use, reuse, recycling and final disposal. From this point, we can gather that whole, local, low-packaging foods are best for the environment because they require less of the aforementioned environmental impact factors. Around the world, 4 billion people live on an animal based diet, while two billion people live on a plant based diet.
Most of the population in the United States follows an animal based diet. As for American food production; the US food production system uses 50% of US land area, 80% of the freshwater supply, and 17% of fossil fuel energy in the country. Agriculture, before it was industrialized, was focused on polyculture. This is when multiple crops are grown and harvested at once. Nowadays, most farmers practice monoculture, when a farm produces one mass item at a time. For example, instead of growing cabbage, soy beans, and having some chickens in the yard, Old Macdonald only grows wheat. Monoculture does yield more crop than polyculture, but it requires more non-renewable energy, whereas polyculture relies on solar energy and rain water. Monoculture is widely used due to the immense amount of crop needed to feed animals in industrialized animal agriculture. This furthers the point that environmental efficiency decreases as trophic levels (ranks on the food chain) increase. Livestock actually consume seven times the amount of grain than the US population. Think: couldn’t all of the grain and resources being fed to livestock be used to feed humans? What impact would that have?
Although many animals are fed a grain based diet, grass-fed livestock are more sustainable. So yes, the grass fed butter you buy is theoretically more environmentally sustainable than regular butter, but cows have the greatest negative impact on the environment. (Want dairy and palm-oil free butter? Try Miyoko’s European Style Cultured Vegan Butter) In fact, 80% of agriculture-sourced greenhouse gases are created by cud chewing animals. In a study by Rosi et al, which evaluated the carbon, water, and ecological footprints of various diets; participants following an animal based diet had the worst environmental impact, versus vegetarian, Mediterranean, or vegan diets.
So what does all of this mean? Basically, eating meat and animal products has negative impacts on the environment. Producing animal based foods requires more input (crops fed to animals) and creates less output (meat, dairy eggs). Creating animal products also requires more fossil fuels, land area, and water, and creates more greenhouse gases than plant based foods., According to the Barilla Center for Nutrition, foods that are more nutritious, i.e., foods that should be consumed more, have a lesser environmental impact than unhealthier foods. This doesn’t mean that eating a chicken breast for dinner is going to ruin your body and the environment. This means to consider the environmental impact of the food you eat, and base consumption decisions off of that. Even reducing meat consumption is better than not doing so. Try swapping your beef burger for a more sustainable veggie patty, or steak for sustainably-raised fish, or even adding more veggies to your plate than meat. Small changes can make a big difference in reducing our environmental impact, and hey, they might even taste better.
Sources:
Springman, Marco. “Health and Nutritional Aspects of Sustainable Diet Strategies and Their Association with Environmental Impacts: A Global Modelling Analysis with Country-level Detail.” The Lancet Planetary Health 2, no. 10 (October 2018): E451-461. doi:https://doi.org/10.1016/S2542-5196(18)30206-7.
Sabaté, Joan, and Sam Soret. “Sustainability of Plant-based Diets: Back to the Future.” The American Journal of Clinical Nutrition 100, no. Suppl_1 (2014). doi:10.3945/ajcn.113.071522
Barilla Center for Food and Nutrition. Double Pyramid: Healthy Food for People, Sustainable Food for the Planet. Parma, Italy: BCFN
Pimentel, David, and Marcia Pimentel. “Sustainability of Meat-based and Plant-based Diets and the Environment.” The American Journal of Clinical Nutrition 78, no. 3 (2003). doi:10.1093/ajcn/78.3.660s
Rosi, Alice et al. “Environmental Impact of Omnivorous, Ovo-lacto-vegetarian, and Vegan Diet.” Scientific Reports 7, no. 1 (2017). doi:10.1038/s41598-017-06466-8.
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