Ethics of eating meat: Difference between revisions
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* Arguments of this sort may be motivated by simple [[anthropomorphism]], or the grafting of human feelings and desires onto animals. |
* Arguments of this sort may be motivated by simple [[anthropomorphism]], or the grafting of human feelings and desires onto animals. |
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** The relationship between human and animal [neurology], and thus the feelings of pain and suffering, can be clearly demonstrated by neurophisological similarities. [[ |
** The relationship between human and animal [neurology], and thus the feelings of pain and suffering, can be clearly demonstrated by neurophisological similarities. [[Nonverbal communication]] between specias has also been demonstrated and allows for the communication of emotion between species - humans identify the sound of a slaughtered pig as a cry of desperation and suffering as well as they can identify the roar of a bear as threat and dominance and the yawn of a cat as, well, a yawn. |
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* The simple act of living brings human beings into conflict with literally thousands of animals, including parasites, worms, mosquitoes, pests, rats, and the like, all of which have interests that often directly conflict with the interests and survival of humans. In this respect Singer's reasoning that killing an animal is unethical because "it does not want to die" applies equally to mosquitoes and tapeworms, and on utilitarian grounds, it is not very clear where to draw the line between the interest of a thousand tapeworms vs that of one human being trying to survive. |
* The simple act of living brings human beings into conflict with literally thousands of animals, including parasites, worms, mosquitoes, pests, rats, and the like, all of which have interests that often directly conflict with the interests and survival of humans. In this respect Singer's reasoning that killing an animal is unethical because "it does not want to die" applies equally to mosquitoes and tapeworms, and on utilitarian grounds, it is not very clear where to draw the line between the interest of a thousand tapeworms vs that of one human being trying to survive. |
Revision as of 17:32, 8 October 2006
While many people have no ethical issues with eating meat, others object to the act of killing and eating an animal and/or the agricultural practices surrounding the production of meat. Reasons for objecting in principle to the practice of killing may include a belief in animal rights, or an aversion to inflicting pain or harm on other living creatures, and environmental ethics. Many people, while not being vegetarians, refuse to eat the flesh of some animals, such as cats, dogs, horses or rabbits, or of warm-blooded animals generally. Some people eat only the flesh of animals who have not been particularly mistreated, and abstain from the flesh of animals derived from factory farming or from particular products such as foie gras. Others believe that the treatment which animals undergo in the production of meat and animal products obliges them to never eat meat or use animal products, even if this is a considerable inconvenience to them.
Scope
Approximately 60 billion land animals are raised and slaughtered each year for food. The number of fish and other aquatic animals raised or caught is much larger still, but is unknown. While some see this as a non-problem, others view it as one of the most pressing ethical issues facing us.
Unless otherwise stated, the issues dealt with in this article are about the consumption of the flesh of animals insofar as those animals are sentient beings. Life-forms that are animals in the biological sense but are not sentient are generally not seen as posing specific ethical problems.[1]
- The "animal" in "animal liberation" and "animal rights" refers to all and only those beings that meet the interest requirement. The phrase "sentient being" or "sentient animal" is sometimes employed to make this reference (...). Thus the criterion for being an "animal", in this moral sense, is not the biological criterion that distinguishes fauna from flora. Nor are animal liberationists confused about this, since most of them readily acknowledge that very probably not all biological animals have interests and, consequently, cannot have moral rights.
Personal or public ethical issue
![](http://upload.wikimedia.org/wikipedia/commons/thumb/9/96/Moulard_Duck_Foie_Gras_with_Pickled_Pear.jpg/220px-Moulard_Duck_Foie_Gras_with_Pickled_Pear.jpg)
An ethical issue may or may not be seen as having potential legal consequences. Not all unethical behaviour is illegal.
Many, even among vegetarians, view the choice whether or not to eat animals, or certain animals, as necessarily a personal issue, to be left to the free choice of each individual. Others believe that like many cases of infliction of serious harm on another being, the treatment of non-human animals is in the scope of the law. A number of countries, for instance, have already banned the production of foie gras.
Arguments why eating meat is unethical
Cause least harm
Philosopher Peter Singer believes that if alternative means of survival exist, one ought to choose the option that does not cause unnecessary harm to animals. Singer believes that everyone (with the exception of a small minority of people such as nomadic, hunting and herding societies) is free to choose not to eat meat or use animal products without sacrificing their health.[2]. Alastair Norcross, Associate Professor of Philosophy at Rice University, lays out the case for ethical vegetariansm based animal suffering with a clever metaphor of puppies and chocolote in "Puppies, Pigs, and People: Eating Meat and Marginal Cases" [3].
Rebuttals
- Not eating any meat can be harmful if adequate alternatives are unavailable, see Necessity.
- It can be argued that a diet without meat does not reduce harm to animals, see Farming plants harms animals.
- Many people disagree that humans have an obligation to avoid eating animals even if alternative means of survival persist, on the grounds that animals are not moral agents and cannot claim rights (nor can they be charged with crimes).
- It is not clear that the interest of an animal to survive trumps the interest of a human being to consume it, anymore than it is clear that the interests of a mosquito to feed and survive on human blood trump the interests of the human being bitten to thwart it.
Animals have feelings and can suffer
John Webster, a professor of animal husbandry at Bristol University has been quoted as saying "People have assumed that intelligence is linked to the ability to suffer and that because animals have smaller brains they suffer less than humans. That is a pathetic piece of logic, sentient animals have the capacity to experience pleasure and are motivated to seek it, you only have to watch how cows and lambs both seek and enjoy pleasure when they lie with their heads raised to the sun on a perfect English summer's day. Just like humans."[4]
In his book Animal Liberation, Peter Singer developed a list of qualities in sentient creatures that he believes gives them consideration under utilitarian ethics. This list has been widely referenced by animal rights campaigners and vegetarians. Singer provides a number of reasons to bestow moral consideration on an animal, such as that the animal does not want to die and is given no choice, that the family and friends of that animal may suffer because of its death, that the animal has expectations of future enjoyment which are denied, that the animal enjoys living, and that the animal experiences fear and pain when killed. Some would say that killing an animal could only be justified in extreme circumstances and that the creation of a meal for its taste, convenience or nutritional value is not sufficient cause.
Rebuttals
- This is not an argument against eating meat, rather against making animals suffer, which meat eaters do not necessarily agree with.
- Arguments of this sort may be motivated by simple anthropomorphism, or the grafting of human feelings and desires onto animals.
- The relationship between human and animal [neurology], and thus the feelings of pain and suffering, can be clearly demonstrated by neurophisological similarities. Nonverbal communication between specias has also been demonstrated and allows for the communication of emotion between species - humans identify the sound of a slaughtered pig as a cry of desperation and suffering as well as they can identify the roar of a bear as threat and dominance and the yawn of a cat as, well, a yawn.
- The simple act of living brings human beings into conflict with literally thousands of animals, including parasites, worms, mosquitoes, pests, rats, and the like, all of which have interests that often directly conflict with the interests and survival of humans. In this respect Singer's reasoning that killing an animal is unethical because "it does not want to die" applies equally to mosquitoes and tapeworms, and on utilitarian grounds, it is not very clear where to draw the line between the interest of a thousand tapeworms vs that of one human being trying to survive.
- While animals do have moral rights, if meat wasn't eaten, there would be no domestic animals.
- Counterargument: that we might breed human slaves because if it wasn't for this new slavery system these people wouldn't exist.
Animals are not treated well
![](http://upload.wikimedia.org/wikipedia/commons/thumb/6/63/Barn_hens.jpg/220px-Barn_hens.jpg)
Vegetarianism for ethical reasons has become popular in developed countries particularly because of the spread of factory farming. Factory farms are widely believed to have reduced quality of life for animals compared to their quality of life on traditional farms. Some illustrate that the current mass demand for meat cannot be satisfied without a mass-production system that disregards the welfare of animals. Others believe that practices like well-managed free-ranging and consumption of game could substantially alleviate the demand for mass-produced meat.
Rebuttals
- Tying in eating meat with factory farming is the logical fallacy of guilty by association. Eating meat is by no means explicitly linked to factory farming.
- This is not an argument against eating meat, rather against making animals suffer, which meat eaters do not necessarily agree with.
Damage to the environment
A combination of the Conservation ethic and the supposed environmental benefits of vegetarianism, this argument claims that consuming meat is less ethical than vegetarianism because it is more damaging to the environment. Proponents argue that meat-eating is immoral from an environmental ethics point of view. Based on Kurt Baier's work (The Moral Point of View, 1994) they argue that if the behaviour in question is such that (a) the consequences would be undesirable if everyone did it, (b) all are equally entitled to engage in it, and (c) engaging in this sort of behaviour is an indulgence, not a sacrifice, then such a behaviour should be prohibited by the morality of the group. They cite that human density on Earth is now one person to about 2 hectares of land, and when domestic animals are added, the density is one population equivalent (Borgstrom, 1965) to about 0.3 hectare. If meat consumption doubles in the next forty years, then there will be only half an acre to supply all the needs (water, oxygen, minerals, fibers, living space, as well as food) for each 50-kilogram consumer, not including pets and wildlife, which would be a catastrophic consequence. They further add that 87 percent of US agricultural land is used to raise animals for food, which feed on more than 80 percent of the corn and 95 percent of oats the US produces. Meat animals of the world alone consume food equal to calorific needs of 9 billion people. The additional strain on natural resources is also cited. They also point out that the spread of cattle farming is closely related to deforestation.[citation needed]
A study by Gidon Eshel and Pamela Martin, who are assistant professors of geophysics at the University of Chicago, have found that our consumption of meat may be as detrimental for our environment as it is for our health [5]. Relatedly, the production and consumption of meat and other animal products is associated with the clearing of rainforests, resource depletion, air and water pollution, land and economic inefficiency, and species extinction.
Rebuttals
- The above figures are largely for a western style diet and cultivation. In fact, in many Asian countries where rice is the staple diet, it takes 5,000 litres of water to produce a Kg of rice,[2] while a Kilo of broiler chicken requires only 3,500 litres.[Source:Pimentel, 2003c] Freeranging cattle and goats/sheep require in developing countries require even lesser water requirements since little or no crop is solely cultivated directly as livestock fodder and many goats have water requirements next only to camels making them very significant to the economy of small-scale farmers. [3]
- Much of the farmland used to raise animals is unsuitable for food crops but is suitable for grazing.[citation needed]
- This is an argument concerning the environmental effects of livestock farming, and therefore can be countered with the rebuttals outlined under the preceding section.
Religious opposition
Peoples spiritual belief system or religious doctrine lead a person to the position that eating meat is immoral. Some religions offer reasons why eating meat should not be practised. In the Dharmic religions, Karmas play an important role. Hinduism, Sikhism and Jainism are such religions that support a vegetarian diet and oppose meat eating.
One religion that opposes meat-eating on ethical/moral grounds is Sikhism. Although Sikhs are not all complete vegetarians, the Sikh Scriptures promote a simple vegetarian diet for maximum spiritual and ethical progress. Bhagat Kabir says in the Sri Guru Granth Sahib, the holy book of the Sikhs, "Kabeer, the dinner of beans and rice is excellent, if it is flavored with salt. Who would cut his throat, to have meat with his bread? ((188))" (SGGS page 1374) and also "Kabeer, they oppress living beings and kill them, and call it proper. When the Lord calls for their account, what will their condition be? ((199))" (SGGS page 1375) (see Sikhism on meat for further details).
Rebuttals
- A belief system can also find eating meat to be moral, or even mandatory.
Arguments why eating meat is ethical
Eating meat is a natural behaviour
![](http://upload.wikimedia.org/wikipedia/commons/thumb/2/2e/Chicken_Kiev.jpeg/220px-Chicken_Kiev.jpeg)
Some argue that because meat eating is a natural or traditional behaviour, in some cases necessary for survival, it is excluded from ethical consideration.
Evolutionary scientists have proposed that meat-eating and hunting are major factors in the evolution of humans: "Our fondness for a juicy steak triggered a number of adaptations over countless generations. For instance, our jaws have gotten smaller, and we have an improved ability to process cholesterol and fat." Scientists have found "stone tools for butchering meat, and animal bones with corresponding cut marks on them, first appear in the fossil record about 2.5 million years ago".[6] Further evidence comes from the fact that pre-agricultural societies lived in nomadic tribes or clans that subsisted through a hunting and gathering lifestyle. Hunter-gatherer societies that subsisted into the 20th century all relied on significant portions of meat in their diet and all hunted in order to survive. [7]
Human biology is such that several essential nutrients are far easier to obtain from a diet that includes meat and meat products. Furthermore, some scientists have concluded that the human small intestine is far too short to indicate a solely herbivorous diet, as compared with other primates such as the gorilla (which is almost solely herbivorous). [8] Additional evidence comes from the fact that chimpanzees eat significant portions of meat (approximately 4-10% of their diet) and will organize hunts to catch and eat prey such as colobus monkeys. [9]
Comedian Denis Leary has been quoted as saying "Not eating meat is a decision, eating meat is an instinct." [10]
Rebuttals
- Some people argue on physiological and psychological grounds that eating meat is not a natural behaviour for humans at all, although most evolutionary scientists and anthropologists would disagree.
- Many natural behaviours would be appalling if exhibited by humans.
- Humans are considered morally conscious of their behaviour in a way other animals are not.
- Natural, traditional or evolutionarily beneficial behaviour is not necessarily good.
- This argument may be an example of the appeal to nature or appeal to tradition logical fallacies.
- Some people believe that the choice to eat meat or not is often not a conscious ethical decision, but a reaction to upbringing and society.
Animals feel no pain
![](http://upload.wikimedia.org/wikipedia/commons/thumb/b/be/Lamm_auf_Wiese.jpg/220px-Lamm_auf_Wiese.jpg)
Meat eating has been defended on the belief that animals feel no pain or cannot think and thus are not worthy of ethical consideration. In particular some religions [citation needed] (especially from Christian tradition) believe that animals cannot think because animals have no soul. This view was shared by Descartes, who held the dualist belief that thoughts and feelings such as pain occur in the incorporeal soul rather than the brain. According to Descartes animals have no soul, their actions being the simple cause and effect responses of automata and they are therefore incapable of feeling pain.
Rebuttals
- The denial of animal pain has been largely refuted, especially for higher order animals, by neuroscience, behavioral and evolutionary biology [11] [12]. Conclusive evidence has been found to support that fish and other highly evolved animal do feel pain. In 2003, the BBC website quoted in the article "The first conclusive evidence of pain perception in fish is said to have been found by UK scientists" that "This complements earlier findings that both birds and mammals can feel pain..." [13]. Research and debate on animal intelligence, however, continue to be controversial for their ethical implications.
- Other religions such as Hinduism (see the concept of Karma) and animist traditions believe that not only do animals have souls but that those souls may transmigrate back and to human beings therefore to eat meat might be to kill and eat a deceased human relative. Islam supports the concept of animals having consciousness and even an awareness of or worship God, that animals have the ability to suffer and that human actions to cause animal suffering are not only strictly prohibited by the Prophet but seen as punishable in this life and the next.
- Animals in suffering or stress produce endomorphines the same as human beings and benefit from palliative treatment [4].
- To counter Descartes, other philosophers from Aristotle through to The Peripatetics and his contemporary De la Forge all support the idea of an animal soul. De La Mettrie wrote that " the soul of an animal must be either mortal or immortal, whichever ours [is]" , (146; Thomson, 38) and Rouseau argued the case for animals' sentience and right not to be needlessly suffer.
Being respectful to animals
Many hunter gatherer tribes will apologize to or thank an animal which has been killed, excusing themselves on the basis that they had to eat the animal in order to survive.
Overpopulation
In some areas, certain species of animals have become overpopulated due to human actions such as the killing off of predators and other factors. This overpopulation can cause serious environmental damage. A common example is an excess deer population, which causes damage to forests and gardens, and can lead to starvation within the animal population when conditions become less optimal. Killing animals in this case might alleviate the suffering of others, and provide food without causing undo suffering.
No moral responsibility, no rights
Another argument in favor of meat-eating involves ascribing any kind of rights only to creatures with free will. This theory argues that since animals lack free will, they are unable to exercise 'rights' in any sense. Since the notion of rights, like the notion of morals, cannot be applied to animals, it need not be applied to their being killed. That is, animals that lack rights, free-will, or the ability to reason abstractly, and thus lack any right to life.
Rebuttals
- Free will is a debated concept. Depending on how the concept is defined, and on whether it is seen as valid at all, it is either not evident that non-humans have no free will, or that humans do have free will.
- It is not evident that to have a right one must be able to take on responsibilities, i.e., social contract is a much debated philosophy. Human infants, or those who suffer severe mental illness, for instance, are granted rights but no responsibilities. Proponents of such philosophy reply that humans as a whole are granted rights because as a species we are normally able to take on moral duties; for example, infants will usually grow up into an adult capable of exercising moral judgment. It does not imply that each human has to be tested on a case-by-case basis.
- It is not evident that the ethical issue of eating meats depends on granting rights to animals. Utilitarian philosophers such as Peter Singer argue that all beings' interests must be given consideration; without any reference to rights.
Health
![](http://upload.wikimedia.org/wikipedia/commons/thumb/a/af/Cyanocobalamin-3D-sticks.png/220px-Cyanocobalamin-3D-sticks.png)
A vegetarian diet requires special effort to compensate, in order to ensure enough access to balanced amino acids, fatty acid nutrients, and other sources of health which are normally obtained from meat.[5]
Many argue that the fats obtained from eating meat are necessary for brain development. [6] Moreover, Omega 3 which improves the life expectancy and reduces medical problems are found in large amounts in fish and many studies have associated a positive health benefit for those eating seafood regularly. [7] [8] They also argue fatty acids obtained from eating meat are necessary for bone marrow. [citation needed]The protein from grains, soy, and beans do not have the fats necessary for this.[citation needed]
Some suggest that refraining from eating meat causes Vitamin B-12 deficiencies. They say that Vitamin B-12 is essential to human life, as it is essential to the formation of nucleic acids and nearly all body tissues. Vitamin B-12 cannot be obtained from plants, and that most of the Vitamin B-12 found in cereals and pills could be useless, as Vitamin B-12 occurs in many analogues, and only one analogue can be used by humans. The deficiency of B-12 has been linked to Alzheimer's disease, and can cause mood swings, depression, mental slowness, weakness, fatigue, and memory problems. Some studies have shown that vegetarian mothers are more likely to have children with low cobalamin (Vitamin B12), elevated tHcy and methylmalonic acid[9]. Other studies have gone as far as claiming that vegetarian mothers are more likely to have children with birth defects[10].
The belief that it is not healthy to abstain from meat, and that abstaining from meat during pregnancy could harm a child, could outweigh ethical consideration for animals.
Studies also have shown that soy could, in fact, be linked to cancer [11]. In fact, at the Gerson Clinic, an oncology specialist clinic, soy is banned because it is suspected of causing cancer. Also, many say that because soy beans are dipped in alkaline and heated to create soy milk, and that the alkaline processing produces the carcinogen lysinoalaline.[12]
Rebuttals
- Eating fortified foods, B12-tablets or dairy products and eggs may prevent or reduce these health problems.
- The position of The American Dietetic Association’s states, “Appropriately planned vegetarian diets are healthful, nutritionally adequate, and provide health benefits in the prevention and treatment of certain diseases.”[citation needed]
- Many believe that if the cost of health, or even life, is the suffering of others, then this is far too high a price to pay.
Necessity
In certain cultures, such as the Inuit, surviving without meat is not possible due to the climate and local flora and fauna. Certain areas, particularly mountainous areas, are not suitable for producing human crops, yet are still useful for allowing livestock to graze.
Farming plants harms animals
Some argue that vegetarianism actually doesn't reduce the number of animals killed; while vegetarians may reduce the demand for meat for consumption, animals might be killed in indirect ways. For example, critics like Steven Davis, professor of animal science at Oregon State University, argues that the number of wild animals killed in crop production is greater than those killed in ruminant-pasture production. Whenever a tractor goes through a field to plow, disc, cultivate, apply fertilizer and/or pesticide, and harvest, animals are killed. Davis gives a small sampling of field animals in the U. S. that are threatened by intensive crop production, such as: opossum, rock dove, house sparrow, European starling, black rat, Norway rat, house mouse, Chukar, grey partridge, ring-necked pheasant, wild turkey, cottontail rabbit, gray-tailed vole, and numerous species of amphibians. In one small example, an alfalfa harvest caused a 50% decline in the gray-tailed vole population. According to Davis, if all of the cropland in the U. S. were used to produce crops for a vegetarian diet, it is estimated that around 1.8 billion animals would be killed annually. [14]
Rebuttals
- Most meat consumed by humans is not from pasture animals but from animals fed food from crops, the production of which implies the same kind of indirect harm to animals as the production of crops for direct human consumption. However, much larger crop surfaces are needed for a meat-based diet than for a plant-based one, because of the poor energy conversion ratio from plant food to animal flesh. Thus the total amount of harm entailed to field animals is certainly much greater for a standard meat-based diet than for a plant-based one.
- The above figure given by Davis of 1.8 billion animals that would be killed annually in the field in the U.S. if everyone went vegetarian is actually much smaller than the number of animals currently slaughtered in the U.S. (approximately 10 billion "poultry" animals, according to United Poultry Concerns), not to mention the animals who are killed in the field if crops are used to feed the animals raised.
- It may be true that a few forms of meat consumption -- perhaps, eating the meat from animals raised on pastures -- kills fewer animals than some, or even most, forms of plant production. Such meat production might then be ethically preferable, from an abstract point of view. However, eating meat may also have a symbolic value, as a statement that the life of the animal eaten is of little worth. Only in a society where the interests of other sentient beings are given due consideration can methods be devised to minimize the harm done to animals in the production of crops. To work towards such a society, it is necessary to forgo the consumption of the flesh of animals.
- The animal populations and death caused in Davis's studies are artificially high due to the industrialisation of agriculture on one hand and harvesting methods on the other. The issue is one of intent. Vegetarianism does not intend to go out kill animals and it is entirely within conception to evolve or revert to a more sustainable or cruelty limited system. Davis's critique is actually a critique of the practises of industrial agriculture feeding the meat industry and has little to do with vegetarianism.
Farming animals keeps them alive
Some critics of vegetarianism believe that human society has a responsibility to maintain the animal species that have become dependent on human husbandry for survival. They suggest that hundreds of years of selective breeding in domestic animal species has made them dependent on human farming. An expansion of this argument is that if a society had a sudden and drastic conversion to vegetarianism, there would be no economically viable reason for keeping certain livestocks--meaning the only viable way to free land for arable farming would be the mass culling of animals. While critics argue that some level of animal husbandry would be maintained for other animal products like wool, milk, eggs etc., supporters of this argument point out that selective breeding has created breeds of animals which have been bred specifically for their meat.
Rebuttals
- The principle that not bringing a being into existence is ethically inferior to creating a being and then killing it is not universally accepted.
References
- ^ S.F. Sapontzis, Morals, Reason and Animals (Temple University Press, Philadelphia, 1987), Chapter 5, "What Liberating Animals Is and Isn't About":
- ^ http://www.ucalgary.ca/~powlesla/personal/hunting/rights/singer.txt
- ^ Norcross, A. 2004. Puppies, Pigs, and People: Eating Meat and Marginal . Philosophical Perspectives 18. A penultimate draft can be freely retrieved from http://www.ruf.rice.edu/~norcross/Puppies.pdf
- ^ Leake, Jonathan. (February 27, 2005)The secret life of moody cows The Sunday Times - Britain. URL accessed on March 22, 2006.
- ^ "Meat-Eaters Aiding Global Warming?: New Research Suggests What You Eat as Important as What You Drive" http://abcnews.go.com/Technology/story?id=1856817&page=1
- ^ [1]
- ^ Leakey, Richard. Origins
- ^ Buss, David. Evolutionary Psychology: The New Science of the Mind
- ^ Goodall, Jane. In the Shadow of Man
- ^ http://www.imdb.com/title/tt0248752/quotes Memorable Quotes from No Cure for Cancer (1992) (TV)
- ^ http://articles.animalconcerns.org/ar-voices/archive/pain.html Do Animals Feel Pain? by Peter Singer
- ^ http://www.wellcome.ac.uk/en/pain/microsite/culture2.html Can animals feel pain? by Lynne U Sneddon
- ^ http://news.bbc.co.uk/1/hi/sci/tech/2983045.stm "Fish do feel pain, scientists say" by Alex Kirby, BBC News Online environment correspondent
- ^ Davis, S.L. (2001). "The least harm principle suggests that humans should eat beef, lamb, dairy, not a vegan diet." EurSafe 2001. Food Safety, Food Quality and Food Ethics. Proceedings of the Third Congress of the European Society for Agricultural and Food Ethics. pp 449-450.
- Davis, B et al. Becoming Vegan: The Complete Guide to Adopting a Healthy Plant-Based Diet. Tennessee: Book Publishing Company, 2000.
- Hyperhomocysteinemia and B-vitamin deficiencies in infants and children.