Environmental Issues Posed by Meat-Based Diet

by kristen_mooney on February 7, 2015 - 2:23pm

Many overlook the detrimental environmental effects their diets pose on the surrounding environment each and every day. Although one may strongly advocate for sustainability through recycling, composting, or simply producing less, many often forget the very threats their dietary practices may cause. 

When it comes to the meat industry, the excessive use of fossil fuels, waste, water, land, and other raw marerials are of great concern.  "Worldwide, an estimated 2 billion people live primarily on a meat-based diet, while an estimated 4 billion live primarily on a plant-based diet. The US food production system uses about 50% of the total US land area, 80% of the fresh water, and 17% of the fossil energy used in the country. The heavy dependence on fossil energy suggests that the US food system, whether meat-based or plant-based, is not sustainable" (Pimentel 2003). With that being said, it has been proven that practicing a vegetarian or vegan diet is much more sustainably sound than that of a meat-based diet.  

"More than 99.2% of US food is produced on land, while < 0.8% comes from oceans and other aquatic ecosystems. The continued use and productivity of the land is a growing concern because of the rapid rate of soil erosion and degradation throughout the United States and the world. Each year about 90% of US cropland loses soil at a rate 13 times above the sustainable rate of 1 ton/ha/y. About 60% of United States pasture land is being overgrazed and is subject to accelerated erosion" (Pimentel 2003). Land use is not only that of concern. Considering water, producing 1 kg of animal protein requires about 100 times more water than producing 1 kg of grain protein. On rangeland for forage production, more than 200 000 L of water are needed to produce 1 kg of beef (although animals vary in the amounts of water required for their production) (Pimentel 2003)

The major threat to future survival and to US natural resources is rapid population growth. The US population of 285 million is projected to double to 570 million in the next 70 years, which will place greater stress on the already-limited supply of energy, land, and water resources. These vital resources will have to be divided among ever greater numbers of people (Pimentel 2003). Where here, does the problem lie? Will it soon be necessary to impliment some sort of population control? Or will we continue to grow, eat, and expand our territory until there is virtually nothing left for us?



Pimentel, David; Pimentel, Marcia. Sustainability of Meat-Based and Plant-Based Diets and the Environment. 2003. The American Journal of Clinical Nutrution. Web Accessed February 07, 2015. Available at: http://ajcn.nutrition.org/content/78/3/660S.full.pdf+html'.


The impacts of meat consumption on the environment are of great concern as you mention in your article. Nevertheless, they are often overlooked by environmentalists. Hence, I congratulate you for having taken the time to explore this issue.

First, I completely agree that food production takes a large portion of the US land area. As a matter of fact, this is a global problem. Specifically, the livestock production takes 70% of all agricultural land, and 30% of the Earth’s global surface (Ilea, 2). Thus, one of the main causes of global deforestation is animal farming (Ilea 8). Indeed, large areas are necessary for animals to graze, and for the production of their feed (Ilea 8). For example, from 1990 to 2000, the Amazon rainforest lost “an area twice the size of Portugal […], most of it to pasture” (Ilea 8). Similarly, 50% of the global production of corn and 80% of that of soy is intended to feed farm animals (Ilea 8). As you partly noted, meat production can, as a result, cause biodiversity losses, soil erosion, and deforestation (Ilea 8).

However, while reading your second paragraph I did not see how your argument proved your conclusion. Indeed, while you state that the US food production, may it be for meat or for plant, use a large amount of energy and is not sustainable, you conclude that a vegan diet is much more sustainable than a meat-based one. Although your conclusion is reasonable, the statistics you provide do not prove it. Nevertheless, in addition to the other environmental consequences aforementioned, the livestock sector does have a significant impact on global warming. As a matter of fact, the livestock sector is responsible for 18% of the global greenhouse gas emissions, which is more than those of all transport (Ilea 2). More specifically, meat production is responsible for 68% of anthropogenic nitrous oxide emissions, 64% of anthropogenic ammonia emissions, and 35–40% of anthropogenic methane emissions (Ilea 4). While methane and nitrous oxide respectively have a global warming potential 23 and 296, nitrous oxide also contribution to the ozone depletion and ammonia plays a significant role in the acidification of rain (Ilea 4).

Similarly, meat production also consumes much more water than the production of cereal, as you noted. Nevertheless, the statistics you provide do not match those I found. Indeed, you mention that producing 1 kg of animal protein requires 100 times more water than 1 kg of grain. What I found, however, is that the production of 1 kg of meat takes from 2.5 to 20 times more water than the production of 1 kg of grain (Ilea 9). As a result, “diets based on meat from grain-fed cattle may take two times more water than pure vegetarian ones” (Ilea 9). Nonetheless, this is a real problem, especially with increasing water shortages that are expected; in fact, “64% of the world’s population is expected to live in water-stressed sectors by 2025” (Ilea 9). Furthermore, the nutrients from livestock’s manure are important sources of water pollution (Ilea 9).

Finally, the rapid population growth will indeed make all these problems worse if no changes are made. The population of the United States is indeed expected to increase, as the projections are now expecting, to 447,883,000 people in 2100 (United Nations, 28).

Hence, while some suggest that the population growth should be controlled, it is certain that developed countries’ consumption of animal products will need to be decreased (Ilea 12). In fact, if the global trend is not changed, the world livestock will consume as much as 4 billion people by 2050 (Ilea 12).

United Nations. “World Population Prospects.” Department of Economic and Social
Affairs, 2017, https://esa.un.org/unpd/wpp/Publications/Files/WPP2017_KeyFindings.pdf

Ilea, Ramona C. "Intensive Livestock Farming: Global Trends, Increased Environmental
Concerns, and Ethical Solutions." Journal of Agricultural and Environmental Ethics, vol. 22, no. 2, 2009, pp. 153-167, Research Library, https://proquest-crc.proxy.ccsr.qc.ca/docview/196572554?accountid=44391, doi:http://dx.doi.org/10.1007/s10806-008-9136-3.