Many people believe that the production of meat and animal products at current and likely future levels is environmentally unsustainable. It is also argued that even if sustainable, modern industrial agriculture is changing ecosystems faster than they can adapt. While vegetarian agriculture produces some of the same problems as animal production, the environmental impact of animal production is significantly greater.
Free-range animal production requires land for grazing, which has prompted encroachment on undeveloped lands and clear cutting. The move into wild lands has increased the rate of species extinction and damaged the services offered by nature, such as natural processing of pollutants. Overgrazed lands lose their ability to support animal production, which makes further agricultural expansion necessary.
Factory farm animal production, while having a smaller land-use footprint, requires large quantities of feed that must be grown over large areas of land. Both free-range and concentrated animal production require large quantities of fresh water and energy, which are currently taken from nonrenewable resources such as aquifers and fossil fuels. Animal production also creates damaging animal waste. In the United States, livestock account for nearly 20% of total methane emissions. Compare this with economic vegetarians, who consider the meat industry economically unsound.
World Hunger: Citing the same efficiency concerns as environmentalist vegetarians and economic vegetarians, many vegetarians see natural resources as being freed up by vegetarianism, particularly "veganism." A popular saying is that even with more food, the problem is shipping all of that food to the starving people. Yet, petroleum is one of the resources freed up for other usage by a vegan diet. Within the Pulitzer-winning book by John Robbins, "Diet for a New America," which uses data primarily sourced from the world's largest body of scientists, AAAS, Robbins explains how the petroleum used in the transportation of farm animals, the later processing of them, and the raising and harvesting of the vast amount of crops fed to farm animals-which is much greater than the amount of crops people would need if we were to eat the crops directly, rather than feeding them to animals, then eating the animals-adds up to greatly increase the amount of petroleum used. So, if more people adopt a vegan diet, not only is more food available, but more petroleum to deliver that food is also available.
Ethical and Animal Rights Issues: Some vegetarians believe that the production and consumption of meat and animal products is inappropriate treatments of animals. Reasons for believing this are varied, and may include a belief in animal rights or an aversion to inflicting harm on other living things.
Some people believe the treatment which animals receive in the production of meat and animal products justifies never eating meat or animal products, even if alternatives do not exist. Others believe that if alternative means of survival exist, it is ethical to choose an alternative, such as vegetarianism. With the exception of a small minority of people, e.g., nomadic hunting and herding societies such as the Inuit and Sami, everyone is free to choose not to eat meat or animal products.
Social Concerns: Some vegetarians are vegetarian because they were raised by vegetarians. Others may have become vegetarians because of a vegetarian partner, family member, or friend. Some people live in regions that are predominantly vegetarian, making meat-eaters a minority. When removed from the social influences that cause vegetarianism, some people will stop being vegetarian while others will remain vegetarian.
Whether for reasons of social concern or perceptions of animal cruelty, vegetarianism has now solidly part of Western culture. No longer is vegetarianism merely the domain of the filthy, unwashed hippies or dull-witted California hot tub socialites. Vegetarianism is now fully mainstream, and getting more mainstream with every delicious vegetarian meal.
