Last updated on: 2/25/2021 | Author: ProCon.org

Americans eat an average of 58 pounds of beef, 96 pounds of chicken, and 52 pounds of pork, per person, per year, according to the United States Department of Agriculture (USDA). Vegetarians, about 5% of the US adult population, do not eat meat (including poultry and seafood). The percentage of Americans who identify as vegetarian has remained steady for two decades. 11% of those who identify as liberal follow a vegetarian diet, compared to 2% of conservatives.

Many proponents of vegetarianism say that eating meat harms health, wastes resources, and creates pollution. They often argue that killing animals for food is cruel and unethical since non-animal food sources are plentiful.

Many opponents of a vegetarian diet say that meat consumption is healthful and humane, and that producing vegetables causes many of the same environmental problems as producing meat. They also argue that humans have been eating and enjoying meat for 2.3 million years. Read more background…

 

Pro & Con Arguments

Pro 1

It is cruel and unethical to kill animals for food when vegetarian options are available, especially because raising animals in confinement for slaughter is cruel, and many animals in the United States are not slaughtered humanely.

Animals are sentient beings that have emotions and social connections. Scientific studies show that cattle, pigs, chickens, and all warm-blooded animals can experience stress, pain, and fear. [100] In 2017, the United States slaughtered a total of 170.5 million animals for food, including 33.7 million cows, 9.2 million chickens, 124.5 million pigs, and 2.4 million sheep. These animals should not have to die painfully and fearfully to satisfy an unnecessary dietary preference.

About 50% of meat produced in the United States came from confined animal feeding operations (CAFOs) in 2008 where mistreated animals live in filthy, overcrowded spaces with little or no access to pasture, natural light, or clean air. [41] In CAFOs pigs have their tails cut short, chickens have their toenails, spurs, and beaks clipped, and cows have their horns removed and tails docked with no painkillers. [32] Pregnant pigs are kept in metal gestation crates barely bigger than the pigs themselves. [35] Baby cows raised for veal are tied up and confined in tiny stalls their entire short lives (3-18 weeks). [147]

The Humane Methods of Slaughter Act (HMSA) mandates that livestock be stunned unconscious before slaughter to minimize suffering. [65] However, birds such as chickens and turkey are exempted from the HMS, and a 2010 report by the US Government Accountability Organization (GAO) found that the USDA was not “taking consistent actions to enforce the HMSA.” [66] [90]

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Pro 2

A vegetarian diet is more healthful than a carnivorous diet.

According to the American Dietetic Association, a vegetarian diet can meet protein requirements, provide all the essential amino-acids (the building blocks of protein), and improve health. It can also provide all the necessary vitamins, fats, and minerals, and can improve one’s health. [1] [2]

According to the USDA and the Food and Agriculture Organization of the United Nations, meat is not an essential part of a healthy diet. [68] [123] Studies have linked heme iron found in red meat with an increased risk of colorectal, stomach, and esophageal cancers. [4] [150] Vegetarian sources of iron like leafy greens and beans contain non-heme iron. [3]

Meat also has high renal acid levels which the body must neutralize by leaching calcium from the bones, which is then passed into urine and lost. [5] There are many sources of healthy vegetarian calcium including tofu, dark leafy greens like kale, spinach, and collard greens, as well as fortified cereals. [128]

A vegetarian diet reduces overuse of antibiotics. Overuse of antibiotics in CAFOs causes antibiotic resistant bacteria to develop, which may endanger human health. [40]

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Pro 3

A vegetarian diet is better for the environment.

Overgrazing livestock hurts the environment through soil compaction, erosion, and harm to native plants and animals. Significant portions of the 11 western states are grazed by livestock. [29] Grazing has been a factor in the listing of at least 171 species of animals and plants under the Endangered Species Act because the large tracts of flat land interrupt natural habitats. [92] Grazing has also damaged streams and riparian areas in the western United States. [93] Abstaining from meat would help restore land more naturally suited to provide habitat for native plants and animals.

A vegetarian diet conserves water. Producing one pound of beef takes about 1,800 gallons of water, about 576 gallons per pound of pork, about 486 gallons per pound of turkey, and about 468 gallons per pound of chicken. A pound of tofu only takes about 302 gallons. [151] [152] [153]

Meanwhile, raising animals for food contributes to air and water pollution. Manure produces toxic hydrogen sulfide and ammonia which pollute the air and leach poisonous nitrates into nearby waters. [32] Runoff laden with manure is a major cause of “dead zones” in 173,000 miles of US waterways, including the 7,700-square-mile dead zone in the Gulf of Mexico. [32] [115]People living near CAFOs often have respiratory problems from hydrogen sulfide and ammonia air pollution. A peer-reviewed 2006 study of Iowa students near a CAFO found 19.7% had asthma – nearly three times the state average of 6.7%. [166]

A vegetarian diet leads to lower greenhouse gas emissions. Greenhouse gases are created by enteric fermentation (aka animal farts and burps), manure decomposition, and deforestation to make room for grazing animals and growing feed. A June 2014 peer-reviewed study found that diets including meat cause the creation of up to 54% more greenhouse gas emissions than vegetarian diets. [134] According to the United Nations Environment Programme, a “worldwide diet change away from animal products” is necessary to stop the worst effects of global climate change. [104]

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Pro 4

Eating fish is not more ethical, environmentally sound, or healthful than eating other animal protein sources.

The US EPA states that “nearly all fish and shellfish” are contaminated by methylmercury (a potent neurotoxin) from industrial pollution. [39] [125] The omega-3 acid ALA found in vegetarian sources like walnut, flax, and olive oils, is converted by the body into EPA and DHA—the essential omega-3 acids found in fish—and sufficient to meet the dietary needs of humans. [54]

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Pro 5

A vegetarian diet lowers risk of diseases.

A vegetarian diet reduces the chances of developing kidney stones and gallstones. Diets high in animal protein cause the body to excrete calcium, oxalate, and uric acid—the main components of kidney stones and gallstones. [6]

A vegetarian diet also lowers the risk of heart disease. [64] Vegetarians had 24% lower mortality from heart disease than meat eaters. [7] A vegetarian diet also helps lower blood pressure, prevent hypertension, and thus reduce the risk of stroke. [8]

Eating meat increases the risk of getting type 2 diabetes in women, and eating processed meat increases the risk in men. [9] [122] A vegetarian diet rich in whole grains, legumes, nuts, and soy proteins helps to improve glycemic control in people who already have diabetes. [10]

Studies show that vegetarians are up to 40% less likely to develop cancer than meat eaters. In 2015 the World Health Organization classified red meat as “probably carcinogenic to humans” and processed meats as “carcinogenic to humans.” [140] Consuming beef, pork, or lamb five or more times a week significantly increases the risk of colon cancer. [102] Eating processed meats such as bacon or sausage increases this risk even further. [148] Diets high in animal protein were associated with a 4-fold increase in cancer death risk compared to high protein diets based on plant-derived protein sources. [132]

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Pro 6

Vegetarians live longer.

A study of 121,342 people found that eating red meat was associated with an increased risk of death from cancer and cardiovascular disease. [121] Another study found that adherence to vegetarian diets or diets very low in meat for 20 years or more can increase life expectancy by 3.6 years. [86] A study of Seventh-Day Adventists who were vegetarian (or ate very little meat) showed longevity increases of 7.28 years for men and 4.42 years for women. [76] And a study of 73,308 people found that a vegetarian diet is associated with a 12% reduction in all-cause mortality. [130]

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Pro 7

Human anatomy has evolved to support a primarily vegetarian diet.

Carnivores have large mouths with pointed teeth, short intestines (three to six times body length), and their livers can detoxify the excess vitamin A absorbed from meat. Human teeth are short and flat, we have long intestines (10-11 times body length), and our livers cannot detoxify excess vitamin A. [62]

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Con 1

Eating meat is natural, not cruel or unethical.

Vegetarians mistakenly elevate the value of animal life over plant life. Research shows that plants also respond electrochemically to threats. [98] [148] Every organism on earth dies at some point so others organisms can live. There is nothing wrong with this cycle.

Further, there is a growing movement to raise “cruelty-free” organic meat. In the United States, animals raised for certified organic meat must be given access to the outdoors, clean air, and water. They cannot be given growth hormones or antibiotics and must be fed organically grown feed free of animal byproducts. [85] According to a 2007 report from the Range Improvement Task Force, organic meat accounted for 3% of total US meat production. [84] By the end of 2012 “natural and organic” beef accounted for 4% of total beef sales in the United States. [129] And, in 2019, 76% of consumers thought that grocery stores should sell meat and poultry raised and slaughtered with good animal welfare standards. [149]

US slaughterhouses must conform to the Humane Methods of Slaughter Act (HMSA) that mandates that livestock be stunned unconscious before slaughter. [65] Many of the largest US meat producers also adhere to the handling standards developed by Dr. Temple Grandin that factor in animal psychology to design transportation devices, stockyards, loading ramps, and restraining systems that minimize stress and calm animals as they are led to slaughter. [87] [88] [89]

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Con 2

Vegetarian diets are not necessarily better for the environment.

Raising beef is often the most efficient way to produce food for humans. About 85% of US grazing land is not suitable for raising crops humans can eat. [27] 98% of the original American prairie lands, along with their native plants and animals, are gone. [60] Most of that land is now covered in corn and wheat fields. Natural prairie grasslands can coexist with sustainable herds of cattle or bison, but they cannot coexist with monocrop agriculture.

Almost 100 million acres of farmland in the Corn Belt (about a third of the total farmland in the area) has lost all topsoil due to erosion, reducing corn and soybean yields by 6%, which is an almost $6 billion loss for farmers. The erosion also pollutes nearby waterways. [154]

94% of US soybeans (a vegetarian staple protein) and 92% of corn were genetically modified (GMOs), immune to herbicides. [43] [155] This immunity allows soy farmers to douse their fields with large quantities of weed-killing herbicides which are toxic to other plants and fish. Some scientists worry that increased herbicide use could create “super weeds.” [44]

Processed vegetarian protein options such as tofu can cause more greenhouse gas pollution than farming meat. A 2010 report from the World Wildlife Fund (WWF) found that the production of soy-based proteins such as tofu could contribute more to greenhouse gas emissions than eating locally produced meat. [16] Giving up all animal products would only give a 7% reduction in green house gas emissions. [106]

Vegetarian diets can cause the death of animals too. According to a 2003 study by Steven Davis at Oregon State University, about six animals per acre, or 52-77% of the animals (such as birds, mice, and rabbits) that live in agricultural crop fields, are killed during harvest. [118]

Further, it is not necessary to become vegetarian to lower our environmental footprint. Some vegetarians eat an unhealthy diet, drive SUVs, and consume eggs and dairy products produced at factory farms (CAFOs). Some meat eaters use solar panels, ride bikes, grow their own vegetables, and eat free-range organic meat. All of a person’s actions make a difference—not just a single act such as eating meat.

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Con 3

Eating meat is part of a healthful diet.

Meat is the most convenient protein source available. In one serving, meat provides all the essential amino acids (the building blocks of protein), as well as essential nutrients such as iron, zinc, and B vitamins. [61] Most plant foods do not provide adequate levels of all the essential amino acids in a single serving.

Saturated fats contain the fat-soluble vitamins A, D, E and K, and the cholesterol from saturated animal fat is needed for the proper function of serotonin receptors in the brain. [49] Low cholesterol levels have been linked to depression. According to a study by researchers at the Institute of Social Medicine and Epidemiology, vegetarians “suffer significantly more often from anxiety disorder and/or depression.” [133] Saturated fats are also essential for building and maintaining cell health, and help the body absorb calcium. [101]

Meat is the best source of vitamin B12, a vitamin necessary to nervous and digestive system health. Although it is also found in eggs and dairy, a peer-reviewed July 2003 study showed two in three vegetarians were vitamin B12 deficient compared to one in 20 meat eaters. [46] [47] Eating meat also provides a better source of iron than a vegetarian diet. The body absorbs 15% to 35% of the heme iron in meat, but only absorbs 2% to 20% of the non-heme iron found in vegetarian sources like leafy greens and beans. [3]

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Con 4

A diet that includes meat does not raise risk of disease.

Saturated fats from meat are not to blame for modern diseases like heart disease, cancer, and obesity. Chemically processed and hydrogenated vegetable oils like corn and canola cause these conditions because they contain harmful free radicals and trans fats formed during chemical processing. [46] [49]

Lean red meat, eaten in moderation, can be a healthful part of a balanced diet. According to researchers at the British Nutrition Foundation, “there is no evidence” that moderate consumption of unprocessed lean red meat has any negative health effects. [50]

However, charring meat during cooking can create over 20 chemicals linked to cancer, and the World Cancer Research Fund finds that processed meats like bacon, sausage, and salami, which contain preservatives such as nitrates, are strongly associated with bowel cancer and should be avoided. [50] They emphasize that lean, unprocessed red meat can be a valuable source of nutrients and do not recommend that people remove red meat from their diets entirely, but rather, that they limit consumption to 11 ounces per week or less. [48]

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Con 5

A diet that includes fish provides the body with essential omega-3 fatty acids.

Fish are a powerful source of the omega-3 fatty acids EPA and DHA which are important for brain function, lowering triglycerides, and reducing the risk of death from heart attacks and strokes. [52]

Although the omega-3 fatty acid ALA can be found in plant oils, the ALA must first be converted by the body into the essential EPA and DHA. The process is inefficient and may not provide the same cardiovascular benefits as eating fish. [53]

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Con 6

Vegetarians do not live longer.

This myth stems from the fact that vegetarians tend to be more health conscious overall, eating a more balanced diet, exercising more, and smoking less than the general population.

When a study from the German Cancer Research Center compared health conscious meat eaters with vegetarians, there was no difference in overall mortality rates. [56]

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Con 7

Humans are omnivores and have evolved to consume even more meat.

Eating meat has been an essential part of human evolution for 2.3 million years.[14] The inclusion of meat in the ancestral diet provided a dense form of nutrients and protein that, when combined with high-calorie low-nutrient carbohydrates such as roots, allowed us to develop our large brains and intelligence. [63]

Evidence shows our taste buds evolved to crave meat’s savory flavor. [57]

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Did You Know?
1. Environmental damage caused by grazing livestock has been a factor in the listing of 171 species under the Endangered Species Act. [92]
2. Two in three vegetarians are vitamin B12 deficient, compared to one in 20 meat eaters, according to a peer-reviewed study in the American Journal of Clinical Nutrition. [47]
3. According to the American Dietetic Association a vegetarian diet can meet protein requirements and provide all the essential amino-acids (the building blocks of protein) a person needs for optimal health. [2]
4. Archaeological evidence shows that eating meat has been an essential part of human evolution for 2.3 million years. [14]
5. The average American gets 67% of his or her dietary protein from animal sources, compared with a world-wide average of 34%. [33]
6. The percentage of Americans who identify as vegetarian has remained steady at around 5% for two decades. 11% of those who identify as liberal follow a vegetarian diet, compared to 2% of conservatives. [136]

 
 

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