Vegetarianism
Description	A vegetarian diet is derived from plants, with or without eggs or dairy.[1]
Origins	Ancient India, ancient Greece; 6th century BCE and earlier
Varieties	Ovo, lacto, ovo-lacto, veganism, raw veganism, fruitarianism, Buddhist vegetarianism

Vegetarianism encompasses the practice of following plant-based diets (fruits, vegetables, etc.), with or without the inclusion of dairy products or eggs, and with the exclusion of meat (red meat, poultry, and seafood). Abstention from by-products of animal slaughter, such as animal-derived rennet and gelatin, may also be practiced.^[2][3]

Vegetarianism can be adopted for different reasons. Many object to eating meat out of respect for sentient life. Such ethical motivations have been codified under various religious beliefs, along with the concept of animal rights. Other motivations for vegetarianism include health, political, environmental, cultural, aesthetic or economic. There are varieties of the diet as well: an ovo-vegetarian diet includes eggs but not dairy products, a lacto-vegetarian diet includes dairy products but not eggs, and an ovo-lacto vegetarian diet includes both eggs and dairy products. A vegan diet excludes all animal products, including eggs, dairy, and honey.

Various packaged or processed foods, including cake, cookies, chocolate and marshmallows, often contain unfamiliar animal ingredients, and may be a special concern for vegetarians due to the likelihood of such additions.^[4] Often, products are scrutinized by vegetarians for animal-derived ingredients prior to purchase or consumption.^[4] Vegetarians vary in their feelings regarding these ingredients, however. For example, while some vegetarians may be unaware of animal-derived rennet's role in the usual production of cheese and may therefore unknowingly consume the product,^[5][6] other vegetarians may not be bothered by its consumption.^[3] The results of a 2009 International survey suggest the standard definition of vegetarianism is different in different nations. Vegetarians in some nations consume more animal products than those in others.^[7]

Semi-vegetarian diets consist largely of vegetarian foods, but may include fish or poultry, or sometimes other meats on an infrequent basis. Those with diets containing fish or poultry may define "meat" only as mammalian flesh and may identify with vegetarianism.^[8][9][10] A pescetarian diet, for example, includes "fish but no meat".^[11] The common use association between such diets and vegetarianism has led vegetarian groups such as the Vegetarian Society to state that diets containing these ingredients are not vegetarian, due to fish and birds being animals.^[12]

Etymology[link]

The Vegetarian Society, founded in 1847, says that the word "vegetarian" is derived from the Latin word vegetus meaning lively or vigorous.^[13] Despite this, the Oxford English Dictionary (OED) and other standard dictionaries state that the word was formed from the term "vegetable" and the suffix "-arian".^[14] The OED writes that the word came into general use after the formation of the Vegetarian Society at Ramsgate in 1847, though it offers two examples of usage from 1839 and 1842.^[15]

History[link]

The earliest records of (lacto) vegetarianism come from ancient India and ancient Greece in the 6th century BCE.^[16] In the Asian instance the diet was closely connected with the idea of nonviolence towards animals (called ahimsa in India) and was promoted by religious groups and philosophers.^[17] Among the Hellenes, Egyptians and others, it had medical or Ritual purification purposes.

Indian emperor Ashoka asserted protection to fauna:

Vegetarian label used in India on packed foodstuff

Following the Christianisation of the Roman Empire in late antiquity, vegetarianism practically disappeared from Europe as it was in other Continents, except India.^[18] Several orders of monks in medieval Europe restricted or banned the consumption of meat for ascetic reasons, but none of them eschewed fish.^[19] (The medieval definition of "fish" included such animals as seals, porpoises, dolphins, barnacle geese, puffins, and beavers.)^[20]

It re-emerged during the Renaissance,^[21] becoming more widespread in the 19th and 20th centuries. In 1847, the first Vegetarian Society was founded in the United Kingdom;^[22] Germany, the Netherlands, and other countries followed. The International Vegetarian Union, a union of the national societies, was founded in 1908. In the Western world, the popularity of vegetarianism grew during the 20th century as a result of nutritional, ethical, and more recently, environmental and economic concerns.

Varieties of vegetarianism[link]

Roadside café near Kullu, India.

There are a number of types of vegetarianism, which exclude or include various foods.

• Ovo vegetarianism includes eggs but not dairy products.
• Lacto vegetarianism includes dairy products but not eggs.
• Ovo-lacto vegetarianism (or lacto-ovo vegetarianism) includes animal/dairy products such as eggs, milk, and honey.
• Veganism excludes all animal flesh and animal products, including milk, honey, and eggs, and may also exclude any products tested on animals, or any clothing from animals.^[23]
• Raw veganism includes only fresh and uncooked fruit, nuts, seeds, and vegetables. Vegetables can only be cooked up to a certain temperature.^[24]
• Fruitarianism permits only fruit, nuts, seeds, and other plant matter that can be gathered without harming the plant.^[25]
• Buddhist vegetarianism (also known as su vegetarianism) excludes all animal products as well as vegetables in the allium family (which have the characteristic aroma of onion and garlic): onion, garlic, scallions, leeks, or shallots.
• Jain vegetarianism includes dairy but excludes eggs and honey, as well as root vegetables.
• Macrobiotic diets consist mostly of whole grains and beans.

Within the 'ovo-' groups, there are many who refuse to consume fertilized eggs (with balut being an extreme example), however such distinction is typically not specifically addressed.

Some vegetarians also avoid products that may use animal ingredients not included in their labels or which use animal products in their manufacturing; for example, sugars that are whitened with bone char, cheeses that use animal rennet (enzymes from animal stomach lining), gelatin (derived from the collagen inside animals' skin, bones and connective tissue), some cane sugar (but not beet sugar) and apple juice/alcohol clarified with gelatin or crushed shellfish and sturgeon, while other vegetarians are unaware of such ingredients.^[4][5][6]

Individuals may describe themselves as "vegetarian" while practicing a semi-vegetarian diet,^[10][26][27] as some dictionary definitions pertaining to vegetarianism vary and include the consumption of fish,^[9] while other definitions exclude fish and all animal flesh.^[12] In other cases, individuals may describe themselves as "flexitarian".^[26] These diets may be followed by those who reduce animal flesh consumed as a way of transitioning to a complete vegetarian diet or for health, environmental, or other reasons. Semi-vegetarian diets include:

• pescetarianism, which includes fish and some other forms of seafood;
• pollotarianism, which includes poultry;
• "pollo-pescetarian", which includes poultry and fish, or "white meat" only;
• macrobiotic diets consisting mostly of whole grains and beans, but may sometimes include fish.

Semi-vegetarianism is contested by vegetarian groups who state that vegetarianism excludes all animal flesh.^[12]

Health benefits and concerns[link]

Scientific endeavors in the area of vegetarianism have shifted from concerns about nutritional adequacy to investigating health benefits and disease prevention.^[28] The American Dietetic Association and Dietitians of Canada have stated that at all stages of life, a properly planned vegetarian diet is "healthful, nutritionally adequate, and provides health benefits in the prevention and treatment of certain diseases." Large-scale studies have shown that mortality from ischaemic heart disease was 30% lower among vegetarian men and 20% lower among vegetarian women than in non-vegetarians.^[29][30][31] Necessary nutrients, proteins, and amino acids for the body's sustenance can be found in vegetables, grains, nuts, soymilk, eggs and dairy.^[32] Vegetarian diets offer lower levels of saturated fat, cholesterol and animal protein, and higher levels of carbohydrates, fibre, magnesium, potassium, folate, and antioxidants such as vitamins C and E and phytochemicals.^[33][34]

Vegetarians tend to have lower body mass index,^[35] lower levels of cholesterol, lower blood pressure, and less incidence of heart disease, hypertension, type 2 diabetes, renal disease, metabolic syndrome,^[36] dementias such as Alzheimer’s disease and other disorders.^[37] Non-lean red meat, in particular, has been found to be directly associated with increased risk of cancers of the esophagus, liver, colon, and the lungs.^[38] Other studies have shown no significant differences between vegetarians and non-vegetarians in mortality from cerebrovascular disease, stomach cancer, colorectal cancer, breast cancer, or prostate cancer.^[30] A 2010 study compared a group of vegetarian and meat-eating Seventh Day Adventists in which vegetarians scored lower on depression tests and had better mood profiles.^[39] However, vegetarians are more likely to be deficient in vitamin B12, leading to increased incidence of osteoporosis^[40] and depression.^[41]

The 2010 version of Dietary Guidelines for Americans, a report issued by the U.S. Department of Agriculture and the U.S. Department of Health and Human Services every five years states:

In prospective studies of adults, compared to non-vegetarian eating patterns, vegetarian-style eating patterns have been associated with improved health outcomes—lower levels of obesity, a reduced risk of cardiovascular disease, and lower total mortality. Several clinical trials have documented that vegetarian eating patterns lower blood pressure.

On average, vegetarians consume a lower proportion of calories from fat (particularly saturated fatty acids); fewer overall calories; and more fiber, potassium, and vitamin C than do non-vegetarians. Vegetarians generally have a lower body mass index. These characteristics and other lifestyle factors associated with a vegetarian diet may contribute to the positive health outcomes that have been identified among vegetarians.^[42]

Nutrition[link]

A fruit stall in Barcelona

Western vegetarian diets are typically high in carotenoids, but relatively low in long-chain n-3 fatty acids and vitamin B₁₂. Vegans can have particularly low intake of vitamin B and calcium if they do not eat enough items such as collard greens, leafy greens, tempeh and tofu (soy). High levels of dietary fiber, folic acid, vitamins C and E, and magnesium, and low consumption of saturated fat are all considered to be beneficial aspects of a vegetarian diet.^[43][44]

Protein[link]

Protein intake in vegetarian diets is only slightly lower than in meat diets and can meet daily requirements for any person, including athletes and bodybuilders.^[45] Studies at Harvard University as well as other studies conducted in the United States, United Kingdom, Canada, Australia, New Zealand and various European countries, confirmed vegetarian diets provide sufficient protein intake as long as a variety of plant sources are available and consumed.^[46] Proteins are composed of amino acids, and a common concern with protein acquired from vegetable sources is an adequate intake of the essential amino acids, which cannot be synthesised by the human body. While dairy and egg products provide complete sources for ovo-lacto vegetarians, the only vegetable sources with significant amounts of all eight types of essential amino acids are lupin beans, soy, hempseed, chia seed, amaranth, buckwheat, peanut butter, and quinoa. However, the essential amino acids can also be obtained by eating a variety of complementary plant sources that, in combination, provide all eight essential amino acids (e.g. brown rice and beans, or hummus and whole wheat pita, though protein combining in the same meal is not necessary). A 1994 study found a varied intake of such sources can be adequate.^[47]

Iron[link]

Vegetarian diets typically contain similar levels of iron to non-vegetarian diets, but this has lower bioavailability than iron from meat sources, and its absorption can sometimes be inhibited by other dietary constituents.^{[citation needed]} Vegetarian foods rich in iron include black beans, cashews, hempseed, kidney beans, lentils, oatmeal, raisins, spinach, black-eyed peas, soybeans, many breakfast cereals, sunflower seeds, chickpeas, tomato juice, tempeh, molasses, thyme, and whole-wheat bread.^[48] The related vegan diets can often be higher in iron than vegetarian diets, because dairy products are low in iron.^[44] Iron stores often tend to be lower in vegetarians than non-vegetarians, and a few small studies report very high rates of iron deficiency (up to 40%,^[49] and 58%^[50] of the respective vegetarian or vegan groups). However, the American Dietetic Association states that iron deficiency is no more common in vegetarians than non-vegetarians (adult males are rarely iron deficient); iron deficiency anaemia is rare no matter the diet.^[51]

[edit] Vitamin B₁₂

Plants are not sources of vitamin B₁₂. According to the United States National Institutes of Health, natural food sources of vitamin B₁₂ are limited to foods that come from animals.^[52] Lacto-ovo vegetarians can obtain B₁₂ from dairy products and eggs, and vegans can obtain it from fortified foods (including some soy products and some breakfast cereals) and dietary supplements.^{[53][54][55][56]} Vitamin B₁₂ can also be obtained from yeast extract products.^[57] The research on vitamin B₁₂ sources has increased in recent years.^[58]

The recommended dietary allowance of B₁₂ in the United States is, per day, 0.4 mcg (0–6 months), rising to 1.8 mcg (9–13 years), 2.4 mcg (14+ years), and 2.8 mcg (lactating female).^[52] The body can preserve stores of B₁₂ for up to 30 years,^[59] and reuses the vitamin without destroying the substance. Clinical evidence has shown a deficiency of B₁₂ in vegans and, to lesser degree, vegetarians.^[40][60]

Fatty acids[link]

Plant-based, or vegetarian, sources of Omega 3 fatty acids include soy, walnuts, pumpkin seeds, canola oil, kiwifruit and especially hempseed, algae, chia seed, flaxseed, echium seed and purslane. Purslane contains more Omega 3 than any other known leafy green. Plant foods can provide alpha-linolenic acid but not the long-chain n-3 fatty acids EPA and DHA, which are found in low levels in eggs and dairy products. Vegetarians, and particularly vegans, have lower levels of EPA and DHA than meat-eaters. While the health effects of low levels of EPA and DHA are unknown, it is unlikely that supplementation with alpha-linolenic acid will significantly increase levels.^{[61][clarification needed]} Recently, some companies have begun to market vegetarian DHA supplements containing seaweed extracts. Similar supplements providing both DHA and EPA have also begun to appear.^[62] Whole seaweeds are not suitable for supplementation because their high iodine content limits the amount that may be safely consumed. However, certain algae such as spirulina are good sources of gamma-linolenic acid (GLA), alpha-linolenic acid (ALA), linoleic acid (LA), stearidonic acid (SDA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and arachidonic acid (AA).^[63][64]

Calcium[link]

Calcium intake in vegetarians is similar to non-vegetarians. Some impaired bone mineralisation has been found among vegans who do not consume enough leafy greens, which are sources of abundant calcium.^[65] However, this is not found in lacto-ovo vegetarians.^[66] Some sources of calcium include collard greens, bok choy, kale, and turnip greens.^[67] Spinach, swiss chard and beet greens are high in calcium, but the calcium is bound to oxalate and therefore it is poorly absorbed.^[68]

Vitamin D[link]

Vitamin D needs can be met via the human body's own generation upon sufficient and sensible exposure to ultraviolet (UV) light in sunlight.^{[citation needed]} Products including milk, soy milk and cereal grains may be fortified to provide a source of Vitamin D^[69] For those who do not get adequate sun exposure and/or food sources, Vitamin D supplementation may be necessary.

[edit] Vitamin D₂

• Plantae
  • Alfalfa (Medicago sativa subsp. sativa), shoot: 4.8 mcg (192 IU) vitamin D₂, 0.1 mcg (4 IU) vitamin D₃^[70]
• Fungus, from USDA nutrient database^[71]:
  • Mushrooms, portabella, exposed to ultraviolet light, raw: Vitamin D (D₂ + D₃): 11.2 mcg (446 IU)
  • Mushrooms, portabella, exposed to ultraviolet light, grilled: Vitamin D (D₂ + D₃): 13.1 mcg (524 IU)
  • Mushrooms, shiitake, dried: Vitamin D (D₂ + D₃): 3.9 mcg (154 IU)
  • Mushrooms, shiitake, raw: Vitamin D (D₂ + D₃): 0.4 mcg (18 IU)
  • Mushrooms, portabella, raw: Vitamin D (D₂ + D₃): 0.3 mcg (10 IU)

Vitamin D₂, or ergocalciferol is found in fungus (except alfalfa which is a plantae) and created from viosterol, which in turn is created when ultraviolet light activates ergosterol (which is found in fungi and named as a sterol from ergot). Any UV-irradiated fungus including yeast form vitamin D₂.^[72] Human bioavailability of vitamin D₂ from vitamin D₂-enhanced button mushrooms via UV-B irradiation is effective in improving vitamin D status and not different to a vitamin D₂ supplement according to study.^[73] For example, Vitamin D₂ from UV-irradiated yeast baked into bread is bioavailable.^[74] By visual assessment or using a chromometer, no significant discoloration of irradiated mushrooms, as measured by the degree of "whiteness", was observed^[75] making it hard to discover if they have been treated without labeling. Claims have been made that a normal serving (approx. 3 oz or 1/2 cup, or 60 grams) of mushrooms treated with ultraviolet light increase their vitamin D content to levels up to 80 micrograms,^[76] or 2700 IU if exposed to just 5 minutes of UV light after being harvested.^[77]

Longevity[link]

A 1999 metastudy combined data from five studies from western countries.^[78] The metastudy reported mortality ratios, where lower numbers indicated fewer deaths, for fish eaters to be 0.82, vegetarians to be 0.84, occasional meat eaters (eat meat less than once per week) to be 0.84. Regular meat eaters and vegans shared the highest mortality ratio of 1.00. The study reported the numbers of deaths in each category, and expected error ranges for each ratio, and adjustments made to the data. However, the "lower mortality was due largely to the relatively low prevalence of smoking in these [vegetarian] cohorts". Out of the major causes of death studied, only one difference in mortality rate was attributed to the difference in diet, as the conclusion states: "...vegetarians had a 24% lower mortality from ischaemic heart disease than non-vegetarians, but no associations of a vegetarian diet with other major causes of death were established."^[78]

In "Mortality in British vegetarians",^[79] a similar conclusion is drawn: "British vegetarians have low mortality compared with the general population. Their death rates are similar to those of comparable non-vegetarians, suggesting that much of this benefit may be attributed to non-dietary lifestyle factors such as a low prevalence of smoking and a generally high socio-economic status, or to aspects of the diet other than the avoidance of meat and fish."^[80]

The Adventist Health Study is an ongoing study of life expectancy in Seventh-day Adventists. This is the only study among others with similar methodology which had favourable indication for vegetarianism. The researchers found that a combination of different lifestyle choices could influence life expectancy by as much as 10 years. Among the lifestyle choices investigated, a vegetarian diet was estimated to confer an extra 1–1/2 to 2 years of life. The researchers concluded that "the life expectancies of California Adventist men and women are higher than those of any other well-described natural population" at 78.5 years for men and 82.3 years for women. The life expectancy of California Adventists surviving to age 30 was 83.3 years for men and 85.7 years for women.^[81]

The Adventist health study is again incorporated into a metastudy titled "Does low meat consumption increase life expectancy in humans?" published in American Journal of Clinical Nutrition, which concluded that low meat eating (less than once per week) and other lifestyle choices significantly increase life expectancy, relative to a group with high meat intake.^[82] The study concluded that "The findings from one cohort of healthy adults raises the possibility that long-term (≥ 2 decades) adherence to a vegetarian diet can further produce a significant 3.6-y increase in life expectancy." However, the study also concluded that "Some of the variation in the survival advantage in vegetarians may have been due to marked differences between studies in adjustment for confounders, the definition of vegetarian, measurement error, age distribution, the healthy volunteer effect, and intake of specific plant foods by the vegetarians." It further states that "This raises the possibility that a low-meat, high plant-food dietary pattern may be the true causal protective factor rather than simply elimination of meat from the diet." In a recent review of studies relating low-meat diet patterns to all-cause mortality, Singh noted that "5 out of 5 studies indicated that adults who followed a low meat, high plant-food diet pattern experienced significant or marginally significant decreases in mortality risk relative to other patterns of intake."

Statistical studies, such as comparing life expectancy with regional areas and local diets in Europe also have found life expectancy considerably greater in southern France, where a low meat, high plant Mediterranean diet is common, than northern France, where a diet with high meat content is more common.^[83]

A study by the Institute of Preventive and Clinical Medicine, and Institute of Physiological Chemistry looked at a group of 19 vegetarians (lacto-ovo) and used as a comparison a group of 19 omnivorous subjects recruited from the same region. The study found that this group of vegetarians (lacto-ovo) have a significantly higher amount of plasma carboxymethyllysine and advanced glycation endproducts (AGEs) compared to this group of non-vegetarians.^[84] Carboxymethyllysine is a glycation product which represents "a general marker of oxidative stress and long-term damage of proteins in aging, atherosclerosis and diabetes." "Advanced glycation end products (AGEs) may play an important adverse role in process of atherosclerosis, diabetes, aging and chronic renal failure."

Food safety[link]

E. coli contamination in food has been linked to industrial-scale meat and dairy farms.^[85] E. coli infections in the US during 2006 that were traced to spinach and onions were later determined to have been caused by a neighbouring cattle and wild pig farm whose feces had contaminated the water supply.^[86][87][88]

Transmission of pathogenic E. coli often occurs via fecal-oral transmission.^[89][90][91] Common routes of transmission include unhygienic food preparation^[90] and farm contamination.^[92][93][94] Dairy and beef cattle are primary reservoirs of the E. coli strain O157:H7,^[95] and they can carry it asymptomatically and shed it in their feces.^[95] Food products associated with E. coli outbreaks include raw ground beef,^[96] raw seed sprouts or spinach,^[92] raw milk, unpasteurized juice, and foods contaminated by infected food workers via fecal-oral route.^[90] In 2005, some people who had consumed triple-washed, pre-packaged lettuce were infected with E. coli.^[97] In 2007, packaged lettuce salads were recalled after they were found to be contaminated with E. coli.^[98] E. coli outbreaks have been traced to unpasteurised apples,^[99] orange juice, milk, alfalfa sprouts,^[100] and water.^[101]

Outbreaks of salmonella have been traced to peanut butter, frozen pot pies & puffed vegetable snacks.^[102] Bovine spongiform encephalopathy (BSE), also known as mad cow disease, is linked by the World Health Organization to Creutzfeldt–Jakob disease in humans.^[103]

There have been reports of fears of foot-and-mouth disease in sheep, PCBs in farmed salmon, mercury in fish, dioxin concentrations in animal products, artificial growth hormones, antibiotics, lead and mercury,^[104] pesticide contamination of vegetables and fruits, banned chemicals being used to ripen fruits.^{[105][106][107]}

Medical use[link]

In Western medicine, patients are sometimes advised to adhere to a vegetarian diet.^[108] Vegetarian diets have been used as a treatment for rheumatoid arthritis, but the evidence is inconclusive whether this is effective.^[109] Certain alternative medicines, such as Ayurveda and Siddha, prescribe a vegetarian diet as a normal procedure. Maya Tiwari notes that Ayurveda recommends small portions of meat for some people, though "the rules of hunting and killing the animal, practiced by the native peoples, were very specific and detailed". Now that such methods of hunting and killing are not observed, she does not recommend the use of "any animal meat as food, not even for the Vata types."^[110]

Physiology[link]

Humans are omnivorous, capable of consuming a wide variety of plant and animal material.^[111][112] Nutritional experts believe that early hominids evolved into eating meat as a result of huge climatic changes that took place three to four million years ago, when forests and jungles dried up and became open grasslands and opened hunting and scavenging opportunities.^[113][114]

Animal-to-human disease transmissions[link]

The consumption of meat can cause a transmission of a number of diseases from animals to humans.^[115] The connection between infected animal and human illness is well established in the case of salmonella; an estimated one-third to one-half of all chicken meat marketed in the United States is contaminated with salmonella.^[115] Only recently, however, have scientists begun to suspect that there is a similar connection between animal meat and human cancer, birth defects, mutations, and many other diseases in humans.^[115][116] The rate of disease among chickens is so high that the Department of Labor has ranked the poultry industry as one of the most hazardous occupations.^[115] 20% of all cows are afflicted with a variety of cancer known as bovine leukemia virus (BLV).^[115] Studies have increasingly linked BLV with HTLV-1, the first human retrovirus discovered to cause cancer.^[115] Scientists have found that a bovine immunodeficiency virus (BIV), the equivalent of the AIDS virus in cows, can also infect human cells.^[115] It is supposed that BIV may have a role in the development of a number of malignant or slow viruses in humans.^{[115][clarification needed]}

The proximity of animals in industrial-scale animal farming leads to an increased rate of disease transmission.^[117]

Transmission of animal influenza viruses to humans has been documented, but illness from such cases is rare compared to that caused by the now common human-adapted older influenza viruses,^[118] transferred from animals to humans in the more distant past.^{[nb 1][120][121][122]} The first documented case was in 1959, and in 1998, 18 new human cases of H5N1 influenza were diagnosed, in which six people died. In 1997 more cases of H5N1 avian influenza were found in chickens in Hong Kong.^[118]

Whether tuberculosis originated in cattle and was then transferred to humans, or diverged from a common ancestor infecting a different species, is currently unclear.^[123] The strongest evidence for a domestic-animal origin exists for measles and pertussis, although the data do not exclude a non-domestic origin.^[124]

According to the 'Hunter Theory', the "simplest and most plausible explanation for the cross-species transmission" the AIDS virus was transmitted from a chimpanzee to a human when a bushmeat hunter was bitten or cut while hunting or butchering an animal.^[125]

Historian Norman Cantor suggests the Black Death might have been a combination of pandemics including a form of anthrax, a cattle murrain. He cites many forms of evidence including the fact that meat from infected cattle was known to have been sold in many rural English areas prior to the onset of the plague.^[126]

Eating disorders[link]

The American Dietetic Association indicates that vegetarian diets may be more common among adolescents with eating disorders but that the evidence suggests that the adoption of a vegetarian diet does not lead to eating disorders, rather that "vegetarian diets may be selected to camouflage an existing eating disorder."^[127] Other studies and statements by dietitians and counselors support this conclusion.^{[nb 2][129]}

Ethics and diet[link]

Various ethical reasons have been suggested for choosing vegetarianism, usually predicated on the interests of non-human animals.

In many societies, controversy and debate have arisen over the ethics of eating animals. Some people, while not vegetarians, refuse to eat the flesh of certain animals due to cultural taboo, such as cats, dogs, horses, or rabbits. Others support meat eating for scientific, nutritional and cultural reasons, including religious ones. Some meat eaters abstain from the meat of animals reared in particular ways, such as factory farms, or avoid certain meats, such as veal or foie gras. Some people follow vegetarian or vegan diets not because of moral concerns involving the raising or consumption of animals in general, but because of concerns about the specific treatment and practises involved in the raising and slaughter of animals, i.e. factory farming and the industrialisation of animal slaughter. Others still avoid meat because meat production is claimed to place a greater burden on the environment than production of an equivalent amount of plant protein.

Ethical objections based on consideration for animals are generally divided into opposition to the act of killing in general, and opposition to certain agricultural practices surrounding the production of meat.

Ethics of killing for food[link]

Princeton University professor and founder of the animal liberation movement, Peter Singer, believes that if alternative means of survival exist, one ought to choose the option that does not cause unnecessary harm to animals. Most ethical vegetarians argue that the same reasons exist against killing animals to eat as against killing humans to eat. Singer, in his book Animal Liberation listed possible qualities of sentience in non-human creatures that gave such creatures the scope to be considered under utilitarian ethics, and this has been widely referenced by animal rights campaigners and vegetarians. Ethical vegetarians also believe that killing an animal, like killing a human, can only be justified in extreme circumstances and that consuming a living creature for its enjoyable taste, convenience, or nutritional value is not sufficient cause. Another common view is that humans are morally conscious of their behaviour in a way other animals are not, and therefore subject to higher standards.^[130]

Opponents of ethical vegetarianism argue that animals are not moral equals to humans and so consider the comparison of eating livestock with killing people to be fallacious. This does not excuse cruelty, but it does mean animals are not morally equivalent to humans and do not possess the rights a human has.^[131]

Treatment of animals[link]

Ethical vegetarianism has become popular in developed countries particularly because of the spread of factory farming, faster communications, and environmental consciousness. Some believe that the current mass demand for meat cannot be satisfied without a mass-production system that disregards the welfare of animals, while others believe that practices like well-managed free-ranging and consumption of game, particularly from species whose natural predators have been significantly eliminated, could substantially alleviate the demand for mass-produced meat.^{[citation needed]}

Religion and diet[link]

Indian cuisine offers a wide range of vegetarian delicacies because Hinduism, practiced by majority of India's populace, encourages vegetarian diet. Shown here is a vegetarian thali.

Jainism teaches vegetarianism as moral conduct as do some major^[132] sects of Hinduism. Buddhism in general does not prohibit meat eating, while Mahayana Buddhism encourages vegetarianism as beneficial for developing compassion.^[133] Other denominations that advocate a vegetarian diet include the Seventh-day Adventists, the Rastafari movement, the Ananda Marga movement and the Hare Krishnas. Sikhism^{[134][135][136]} does not equate spirituality with diet and does not specify a vegetarian or meat diet.^[137]

Hinduism[link]

Most major paths of Hinduism hold vegetarianism as an ideal. There are three main reasons for this: the principle of nonviolence (ahimsa) applied to animals;^[138] the intention to offer only "pure" (vegetarian) food to a deity and then to receive it back as prasad;^[139] and the conviction that non-vegetarian food is detrimental for the mind and for spiritual development. Hindu vegetarians usually eschew eggs but consume milk and dairy products, so they are lacto-vegetarians.

However, the food habits of Hindus vary according to their community and according to regional traditions. Historically and currently, those Hindus who eat meat prescribe Jhatka meat.^[140]

Jainism[link]

Followers of Jainism believe that everything from animals to inanimate objects have life in different degree and they go to great lengths to minimise any harm to it. Most Jains are lacto-vegetarians but more devout Jains do not eat root vegetables because this would involve the killing of plants. Instead they focus on eating beans and fruits, whose cultivation do not involve killing of plants. No products obtained from dead animals are allowed. Jains hold self termination from starvation as the ideal state and some dedicated monks do perform this act of self annihilation. This is for them an indispensable condition for spiritual progress.^[141][142] Some particularly dedicated individuals are fruitarians.^[143] Honey is forbidden, because its collection is seen as violence against the bees. Some Jains do not consume plant parts that grow underground such as roots and bulbs, because tiny animals may be killed when the plants are pulled up.^[144]

Buddhism[link]

A vegetarian dinner at a Japanese Buddhist temple

Theravadins in general eat meat.^[145] If Buddhist monks "see, hear or know" a living animal was killed specifically for them to eat, they must refuse it or else incur an offense.^[146] However, this does not include eating meat which was given as alms or commercially purchased. In the Theravada canon, Buddha did not make any comment discouraging them to eat meat (except specific types, such as human, elephant, horse, dog, snake, lion, tiger, leopard, bear, and hyena flesh^[147]) but he specifically refused to institute vegetarianism in his monastic code when a suggestion had been made^{[citation needed]}.

In several Sanskrit texts of Mahayana Buddhism, Buddha instructs his followers to avoid meat.^{[148][149][150][151]} However, each branch of Mahayana Buddhism selects which sutra to follow, and some branches, including the majority of Tibetan and Japanese Buddhists, do eat meat, while many Chinese Buddhist branches do not.

Sikhism[link]

The tenets of Sikhism do not advocate a particular stance on either vegetarianism or the consumption of meat,^{[152][153][154][155]} but leave the decision of diet to the individual.^[156] The tenth guru, Guru Gobind Singh, however, prohibited "Amritdhari" Sikhs, or those that follow the Sikh Rehat Maryada (the Official Sikh Code of Conduct)^[157] from eating Kutha meat, or meat which has been obtained from animals which have been killed in a ritualistic way. This is understood to have been for the political reason of maintaining independence from the then-new Muslim hegemony, as Muslims largely adhere to the ritualistic halal diet.^[152][156]

"Amritdharis" that belong to some Sikh sects (e.g. Akhand Kirtani Jatha, Damdami Taksal, Namdhari^[158] and Rarionwalay,^[159] etc.) are vehemently against the consumption of meat and eggs (though they do consume and encourage the consumption of milk, butter and cheese).^[160] This vegetarian stance has been traced back to the times of the British Raj, with the advent of many new Vaishnava converts.^[156] In response to the varying views on diet throughout the Sikh population, Sikh Gurus have sought to clarify the Sikh view on diet, stressing their preference only for simplicity of diet. Guru Nanak said that over-consumption of food (Lobh, Greed) involves a drain on the Earth's resources and thus on life.^[161][162] Passages from the Guru Granth Sahib (the holy book of Sikhs, also known as the Adi Granth) say that it is "foolish" to argue for the superiority of animal life, because though all life is related, only human life carries more importance: "Only fools argue whether to eat meat or not. Who can define what is meat and what is not meat? Who knows where the sin lies, being a vegetarian or a non-vegetarian?"^[156] The Sikh langar, or free temple meal, is largely lacto-vegetarian, though this is understood to be a result of efforts to present a meal that is respectful of the diets of any person who would wish to dine, rather than out of dogma.^[155][156]

Judaism[link]

Basket of fresh fruit and vegetables grown in Israel

While it is neither required nor prohibited for Jews to eat meat, a number of medieval scholars of Jewish religion (e.g., Joseph Albo and Isaac Arama) regard vegetarianism as a moral ideal, not just because of a concern for the welfare of animals, but because the slaughter of animals might cause the individual who performs such acts to develop negative character traits. Therefore, their concern was with regard to possible harmful effects upon human character rather than with animal welfare. Indeed, Rabbi Joseph Albo maintains that renunciation of the consumption of meat for reasons of concern for animal welfare is not only morally erroneous but even repugnant.^[163]

One modern-day scholar who is often cited as in favour of vegetarianism is the late Rabbi Abraham Isaac Kook, the Chief Rabbi of Mandate Palestine. In his writings, Rabbi Kook speaks of vegetarianism as an ideal, and points to the fact that Adam did not partake of the flesh of animals. In context, Rabbi Kook makes those comments in his portrayal of the eschatological (messianic) era. However, he personally refrained from eating meat except on the Sabbath and Festivals, and one of his leading disciples, Rabbi David Cohen, known as the "Nazirite" of Jerusalem, was a devout vegetarian. Several other members of Rabbi Kook's circle were also vegetarians.

According to some Kabbalists, only a mystic, who is able to sense and elevate the reincarnated human souls and "divine sparks", is permitted to consume meat, though eating the flesh of an animal might still cause spiritual damage to the soul. A number of Orthodox Jewish vegetarian groups and activists promote such ideas and believe that the halakhic permission to eat meat is a temporary leniency for those who are not ready yet to accept the vegetarian diet.^[164]

Translation of the Torah's Ten Commandments states, "Thou shalt not murder."^[165][166] Some people argue that this can also be taken as meaning not to kill at all, animals nor humans, or at least "that one shall not kill unnecessarily," in the same manner that onerous restrictions on slavery in the Bible have been interpreted by modern theologians as to suggest banning the practice.^[167] The Torah also commands people to ritually slaughter animals when killing them, and goes into precise detail on the rituals of both animal sacrifice and ordinary slaughter (shechita). According to medieval sage Rabbi Shlomo Ephraim Luntschitz, author of the Torah commentary Kli Yakar, the complexity of these laws was intended to discourage the consumption of meat.^[168]

Classical Greek and Roman[link]

Ancient Greek philosophy has a long tradition of vegetarianism. Pythagoras was reportedly vegetarian (and studied at Mt. Carmel, where some historians say there was a vegetarian community), as his followers were expected to be. Socrates was reportedly vegetarian, and in his dialogue of what people, or at least Philosopher-rulers, in an ideal republic should eat, he described only vegetarian food. He specified that if meat-eating was allowed, then society would require more doctors.^[169]

Roman writer Ovid concluded his magnum opus Metamorphoses, in part, with the impassioned argument (uttered by the character of Pythagoras) that in order for humanity to change, or metamorphose, into a better, more harmonious species, it must strive towards more humane tendencies. He cited vegetarianism as the crucial decision in this metamorphosis, explaining his belief that human life and animal life are so entwined that to kill an animal is virtually the same as killing a fellow human.

Christianity[link]

Vegetarianism is not a common practice in current Christian culture. However, the Bible Christian Church founded by Reverend William Cowherd in 1809 followed a vegetarian diet.^[171] Cowherd was one of the philosophical forerunners of the Vegetarian Society.^[172] Cowherd encouraged members to abstain from eating of meat as a form of temperance.^[173]

Other churches advocating vegetarianism include the Seventh Day Adventists and traditional monastics. As well, members of the Orthodox Church follow a vegan diet during fasts.^[174] There is also a strong association between the Quakers and vegetarianism dating back at least to the 18th century. The association grew in prominence during the 19th century, coupled with growing Quaker concerns in connection with alcohol consumption, vivisection and social purity. The association between the Quaker tradition and vegetarianism, however, becomes most significant with the founding of the Friends' Vegetarian Society in 1902 "to spread a kindlier way of living amongst the Society of Friends."^[175]

Islam[link]

Followers of Islam, or Muslims, have the freedom of choice to be vegetarian for medical reasons or if they do not personally like the taste of meat. However, the choice to become vegetarian for non-medical reasons can sometimes be controversial. Though some more traditional Muslims may keep quiet about their vegetarian diet, the number of vegetarian Muslims is increasing.^[176]

Vegetarianism has been practiced by some influential Muslims including the Iraqi theologian, female mystic and poet Râbi‘ah al-‘Adawîyah of Basrah, who died in the year 801, and the Sri Lankan sufi master Bawa Muhaiyaddeen who established The Bawa Muhaiyaddeen Fellowship of North America in Philadelphia.^[177] The former Indian president Dr. A. P. J. Abdul Kalam is also famously a vegetarian.^[178]

In January 1996, The International Vegetarian Union announced the formation of the Muslim Vegetarian/Vegan Society.^[179]

Many non-vegetarian Muslims will select vegetarian (or seafood) options when dining in non-halal restaurants. However, this is a matter of not having the right kind of meat rather than preferring not to eat meat on the whole.^[176]

Bahá'í Faith[link]

While there are no dietary restrictions in the Bahá'í Faith, `Abdu'l-Bahá, the son of the religion's founder, noted that a vegetarian diet consisting of fruits and grains was desirable, except for people with a weak constitution or those that are sick.<sup>[180]</sup> He stated that there are no requirements that Bahá'ís become vegetarian, but that a future society should gradually become vegetarian.<sup>[180][181][182]</sup> `Abdu'l-Bahá also stated that killing animals was contrary to compassion.^[180] While Shoghi Effendi, the Guardian of the Bahá'í Faith stated that a purely vegetarian diet would be preferable since it avoided killing animals,^[183] both he and the Universal House of Justice, the governing body of the Bahá'ís have stated that these teachings do not constitute a Bahá'í practice and that Bahá'ís can choose to eat whatever they wish but should be respectful of others' beliefs.^[180]

Rastafari[link]

Within the Afro-Caribbean community, a minority are Rastafari and follow the dietary regulations with varying degrees of strictness. The most orthodox eat only "Ital" or natural foods, in which the matching of herbs or spices with vegetables is the result of long tradition originating from the African ancestry and cultural heritage of Rastafari.^[184] Most Rastafari are vegetarian.^[185]

Utensils made from natural material such as stone or earthenware are preferred.^{[citation needed]}

Environment and diet[link]

Environmental vegetarianism is based on the concern that the production of meat and animal products for mass consumption, especially through factory farming, is environmentally unsustainable. According to a 2006 United Nations initiative, the livestock industry is one of the largest contributors to environmental degradation worldwide, and modern practices of raising animals for food contribute on a "massive scale" to air and water pollution, land degradation, climate change, and loss of biodiversity. The initiative concluded that "the livestock sector emerges as one of the top two or three most significant contributors to the most serious environmental problems, at every scale from local to global."^[186]

In addition, animal agriculture is a large source of greenhouse gases. According to a 2006 report it is responsible for 18% of the world's greenhouse gas emissions as measured in CO₂ equivalents. Livestock sources (including enteric fermentation and manure) account for about 3.1 percent of US anthropogenic GHG emissions expressed as carbon dioxide equivalents.^[187] This EPA estimate is based on methodologies agreed to by the Conference of Parties of the UNFCCC, with 100-year global warming potentials from the IPCC Second Assessment Report used in estimating GHG emissions as carbon dioxide equivalents.

Meat produced in a laboratory (called in vitro meat) may be more environmentally sustainable than regularly produced meat.^[188]

Rearing a relatively small number of grazing animals can be beneficial, as the Food Climate Research Network at Surrey University reports: "A little bit of livestock production is probably a good thing for the environment.^[189]

In May 2009, Ghent, Belgium, was reported to be "the first [city] in the world to go vegetarian at least once a week" for environmental reasons, when local authorities decided to implement a "weekly meatless day". Civil servants would eat vegetarian meals one day per week, in recognition of the United Nations' report. Posters were put up by local authorities to encourage the population to take part on vegetarian days, and "veggie street maps" were printed to highlight vegetarian restaurants. In September 2009, schools in Ghent are due to have a weekly veggiedag ("vegetarian day") too.^[190]

Labor conditions and diet[link]

Some groups, such as PETA, promote vegetarianism as a way to offset poor treatment and working conditions of workers in the contemporary meat industry.^[191] These groups cite studies showing the psychological damage caused by working in the meat industry, especially in factory and industrialised settings, and argue that the meat industry violates its labourers' human rights by assigning difficult and distressing tasks without adequate counselling, training and debriefing.^{[192][193][194]} However, the working conditions of agricultural workers as a whole, particularly non-permanent workers, remain poor and well below conditions prevailing in other economic sectors.^[195] Accidents, including pesticide poisoning, among farmers and plantation workers contribute to increased health risks, including increased mortality.^[196] According to the International Labour Organization, agriculture is one of the three most dangerous jobs in the world.^[197]

Economics and diet[link]

Similar to environmental vegetarianism is the concept of economic vegetarianism. An economic vegetarian is someone who practices vegetarianism from either the philosophical viewpoint concerning issues such as public health and curbing world starvation, the belief that the consumption of meat is economically unsound, part of a conscious simple living strategy or just out of necessity. According to the Worldwatch Institute, "Massive reductions in meat consumption in industrial nations will ease their health care burden while improving public health; declining livestock herds will take pressure off rangelands and grainlands, allowing the agricultural resource base to rejuvenate. As populations grow, lowering meat consumption worldwide will allow more efficient use of declining per capita land and water resources, while at the same time making grain more affordable to the world's chronically hungry."^[198]

Taiwanese Buddhist cuisine

Demographics[link]

A research study conducted on more than 8,000 people, and published in the British Medical Journal, suggested that children with an above-average IQ may have a higher chance of becoming vegetarians in their adulthood.^[199]

Gender[link]

A 1992 market research study conducted by the Yankelovich research organisation claimed that "of the 12.4 million people [in the US] who call themselves vegetarian, 68% are female, while only 32% are male".^[200]

At least one study indicates that vegetarian women are more likely to have female babies. A study of 6,000 pregnant women in 1998 "found that while the national average in Britain is 106 boys born to every 100 girls, for vegetarian mothers the ratio was just 85 boys to 100 girls".^[201] Catherine Collins of the British Dietetic Association has dismissed this as a "statistical fluke".^[201]

Country-specific information[link]

See also[link]

	Food portal
	Medicine portal

Notes[link]

References[link]