There have been very few human societies in which no meat or fish are eaten, although in some parts of the world the normal diet is made up largely of staple foods such as rice, with meat and fish being relatively rare additions; this has often been due to poverty rather than choice. In modern Western societies, however, 'voluntary' vegetarianism is on the increase. Currently in 2009 in the UK alone, there are approximately 3 % of the population (1.8 million individuals) are vegetarians, 5 % of the population is partly vegetarian, not eating some types of meat or fish. There are different types of vegetarianism. People who make a choice never to eat meat are vegetarians, although some vegetarians eat fish if it has been caught in the wild, many will not eat flesh of any sort. Some people are vegans, choosing not to eat any animal product, include eggs and dairy (milk) foods such as cheese, butter and yoghurt. Vegans and many vegetarians also refuse to wear leather or fur because it comes from animals.
This debate is about whether it is right for human beings to eat other animals (including fish). To take an even more absolute line, the proposition could argue for veganism - this means eating no dairy produce or eggs (as well as no meat or fish).
As evolved human beings it is our moral duty to inflict as little pain as possible for our survival. So if we do not need to inflict pain to animals in order to survive, we should not do it. Farm animals such as chickens, pigs, sheep, and cows are sentient living beings like us - they are our evolutionary cousins and like us they can feel pleasure and pain. The 18th century utilitarian philosopher Jeremy Bentham even believed that animal suffering was just as serious as human suffering and likened the idea of human superiority to racism. It is wrong to farm and kill these animals for food when we do not need to do so. The methods of farming and slaughter of these animals are often barbaric and cruel - even on supposedly 'free range' farms. Ten billion animals were slaughtered for human consumption each year, stated PETA. And unlike the farms long time ago, where animals roamed freely, today, most animals are factory farmed: crammed into cages where they can barely move and fed a diet adulterated with pesticides and antibiotics. These animals spend their entire lives in their “prisoner cells” so small that they can't even turn around. Many suffer serious health problems and even death because they are selectively bred to grow or produce milk or eggs at a far greater rate than their bodies are capable of coping with. At the slaughterhouse, there were millions of others who are killed every year for food.
Further on Tom Regan explains that all duties regarding animals are indirect duties to one another from a philosophical point of view. He illustrates it with an analogy regarding children: “Children, for example, are unable to sign contracts and lack rights. But they are protected by the moral contract nonetheless because of the sentimental interests of others. So we have, then, duties involving these children, duties regarding them, but no duties to them. Our duties in their case are indirect duties to other human beings, usually their parents.” With this he supports the theory that animals must be protected from suffering, as it is moral to protect any living being from suffering, not because we have a moral contract with them, but mainly due to respect of life and recognition of suffering itself.
There is a great moral difference between humans and animals. Unlike animals, humans are capable of rational thought and can alter the world around them. Other creatures were put on this earth for mankind to use, and that includes eating meat. For all these reasons we say that men and women have rights and that animals don’t. This means that eating meat is in no way like murder. It is natural for human beings to farm, kill, and eat other species. In the wild there is a brutal struggle for existence. The fact that we humans have succeeded in that struggle by exploiting our natural environment means that we have a natural right over lower species. In fact farming animals is much less brutal than the pain and hardship that animals inflict on each other naturally in the wild.
Eating meat does not need to mean cruelty to animals. There are a growing number of organic and free-range farms that can provide meat without cruelty to animals. Similarly, it might be reasonable to argue for an extension of animal welfare laws to protect farm animals - but that does not mean that it is wrong in principle to eat meat.
Becoming a vegetarian is an environmentally friendly thing to do. Modern farming is one of the main sources of pollution in our rivers. Beef farming is one of the main causes of deforestation, and as long as people continue to buy fast food in their billions, there will be a financial incentive to continue cutting down trees to make room for cattle. Because of our desire to eat fish, our rivers and seas are being emptied of fish and many species are facing extinction. Energy resources are used up much more greedily by meat farming than my farming cereals, pulses etc. Eating meat and fish not only causes cruelty to animals, it causes serious harm to the environment and to biodiversity. For example consider Meat production related pollution and deforestation
At Toronto’s 1992 Royal Agricultural Winter Fair, Agriculture Canada displayed two contrasting statistics: “it takes four football fields of land (about 1.6 hectares) to feed each Canadian” and “one apple tree produces enough fruit to make 320 pies.” Think about it — a couple of apple trees and a few rows of wheat on a mere fraction of a hectare could produce enough food for one person!
The 2006 U.N. Food and Agriculture Organization (FAO) report concluded that worldwide livestock farming generates 18% of the planet's greenhouse gas emissions — by comparison, all the world's cars, trains, planes and boats account for a combined 13% of greenhouse gas emissions. 
As a result of the above point producing meat damages the environment. The demand for meat drives deforestation. Daniel Cesar Avelino of Brazil's Federal Public Prosecution Office says “We know that the single biggest driver of deforestation in the Amazon is cattle.” This clearing of tropical rainforests such as the Amazon for agriculture is estimated to produce 17% of the world's greenhouse gas emissions. Not only this but the production of meat takes a lot more energy than it ultimately gives us chicken meat production consumes energy in a 4:1 ratio to protein output; beef cattle production requires an energy input to protein output ratio of 54:1.
The same is true with water use due to the same phenomenon of meat being inefficient to produce in terms of the amount of grain needed to produce the same weight of meat, production requires a lot of water. Water is another scarce resource that we will soon not have enough of in various areas of the globe. Grain-fed beef production takes 100,000 liters of water for every kilogram of food. Raising broiler chickens takes 3,500 liters of water to make a kilogram of meat. In comparison, soybean production uses 2,000 liters for kilogram of food produced; rice, 1,912; wheat, 900; and potatoes, 500 liters. This is while there are areas of the globe that have severe water shortages. With farming using up to 70 times more water than is used for domestic purposes: cooking and washing. A third of the population of the world is already suffering from a shortage of water. Groundwater levels are falling all over the world and rivers are beginning to dry up. Already some of the biggest rivers such as China’s Yellow river do not reach the sea.
With a rising population becoming vegetarian is the only responsible way to eat.
You don’t have to be vegetarian to be green. Many special environments have been created by livestock farming – for example chalk down land in England and mountain pastures in many countries. Ending livestock farming would see these areas go back to woodland with a loss of many unique plants and animals. Growing crops can also be very bad for the planet, with fertilisers and pesticides polluting rivers, lakes and seas. Most tropical forests are now cut down for timber, or to allow oil palm trees to be grown in plantations, not to create space for meat production.
British farmer and former editor Simon Farrell also states: “Many vegans and vegetarians rely on one source from the U.N. calculation that livestock generates 18% of global carbon emissions, but this figure contains basic mistakes. It attributes all deforestation from ranching to cattle, rather than logging or development. It also muddles up one-off emissions from deforestation with on-going pollution.”
He also refutes the statement of meat production inefficiency: “Scientists have calculated that globally the ratio between the amounts of useful plant food used to produce meat is about 5 to 1. If you feed animals only food that humans can eat — which is, indeed, largely the case in the Western world — that may be true. But animals also eat food we can't eat, such as grass. So the real conversion figure is 1.4 to 1.” At the same time eating a vegetarian diet may be no more environmentally friendly than a meat based diet if it is not sustainably sourced or uses perishable fruit and vegetables that are flown in from around the world. Eating locally sourced food can has as big an impact as being vegetarian.
There are significant health benefits to 'going veggie'; a vegetarian diet contains high quantities of fibre, vitamins, and minerals, and is low in fat. (A vegan diet is even better since eggs and dairy products are high in cholesterol.) The risk of contracting many forms of cancer is increased by eating meat: in 1996 the American Cancer Society recommended that red meat should be excluded from the diet entirely. Eating meat also increases the risk of heart disease - vegetables contain no cholesterol, which can build up to cause blocked arteries in meat-eaters. An American study found out that: “that men in the highest quintile of red-meat consumption — those who ate about 5 oz. of red meat a day, roughly the equivalent of a small steak had a 31% higher risk of death over a 10-year period than men in the lowest-consumption quintile, who ate less than 1 oz. of red meat per day, or approximately three slices of corned beef.” A vegetarian diet reduces the risk for chronic degenerative diseases such as obesity, high blood pressure, diabetes and types of cancer including colon, breast, stomach, and lung cancer because of it's low fat/cholesterol content. There are plenty of vegetarian sources of protein, such as beans and bean curd; and spinach is one of the best sources of iron.
The key to good health is a balanced diet, not a meat- and fish-free diet. Meat and fish are good sources of protein, iron, and other vitamins and minerals. Most of the health benefits of a vegetarian diet derive from its being high in fibre and low in fat and cholesterol. These can be achieved by avoiding fatty and fried foods, eating only lean grilled meat and fish, and including a large amount of fruit and vegetables in your diet along with meat and fish. In general, raw, unprocessed meat from the muscle is made up of the following: protein 15 - 22 % Fat 3 - 15 % Minerals, carbohydrates 1 - 5 % Water 65 - 75 %, all things that we need in moderation. A meat- and fish-free diet is unbalanced and makes it more likely that you will go short of protein, iron and some minerals such as B12 for which we are primarily dependent on animal foodstuffs. Also, a vegetarian diet, in the West, is a more expensive option - a luxury for the middle classes. Fresh fruit and vegetables are extremely expensive compared to processed meats, bacon, burgers, sausages etc.
Almost all dangerous types of food poisoning are passed on through meat or eggs. So Campylobacter bacteria, the most common cause of food poisoning in England, are usually found in raw meat and poultry, unpasteurised milk and untreated water. Salmonella come from raw meat, poultry and dairy products and most cases of escherichia coli (E-Coli) food poisoning occur after eating undercooked beef or drinking unpasteurised milk.
Close contact between humans and animals also leads to zoonosis – diseases such as bird ‘flu which can be passed on from animals to humans. Using animal brains in the processed feed for livestock led to BSE in cattle and to CJD in humans who ate beef from infected cows.
Food safety and hygiene are very important for everyone, and governments should act to ensure that high standards are in place particularly in restaurants and other places where people get their food from. But food poisoning can occur anywhere “People don't like to admit that the germs might have come from their own home” and while meat is particularly vulnerable to contamination there are bacteria that can be transmitted on vegetables, for example Listeria monocytogenes can be transmitted raw vegetables.
Almost three-quarters of zoonotic transmissions are caused by pathogens of wildlife origin; even some that could have been caused by livestock such as avian flu could equally have come from wild animals. There is little we can do about the transmission of such diseases except by reducing close contact. Thus changing to vegetarianism may reduce such diseases by reducing contact but would not eliminate them.
Just as meat production can raise health issues, so does the arable farming of plants – examples include GM crops and worries about pesticide residues on fruit and vegetables. The important thing is not whether the diet is meat based or vegetarian; just that we should ensure all food is produced in a safe and healthy way.
Humans are omnivores – we are meant to eat both meat and plants. Like our early ancestors we have sharp canine teeth for tearing animal flesh and digestive systems adapted to eating meat and fish as well as vegetables. Our stomachs are also adapted to eating both meat and vegetable matter. All of this means that eating meat is part of being human. Only in a few western countries are people self-indulgent enough to deny their nature and get upset about a normal human diet. We were made to eat both meat and vegetables - cutting out half of this diet will inevitably mean we lose that natural balance. Eating meat is entirely natural. Like many other species, human beings were once hunters. In the wild animals kill and are killed, often very brutally and with no idea of “rights”. As mankind has progressed over thousands of years we have largely stopped hunting wild animals. Instead we have found kinder and less wasteful ways of getting the meat in our diets through domestication. Farm animals today are descended from the animals we once hunted in the wild.
Human evolved as omnivores over thousands of years. Yet since the invention of farming there is no longer a need for us to be omnivores. Even if we wished to we could no longer collect, hunt and eat our food in the same way as our ancestors as we could not support the human population. We have outstripped the pace of our evolution and if we do not want to be turning ever more land over to farming we have get our food from the most efficient sources, which means being vegetarian.
A vegetarian or vegan diet may result in a person not getting enough iron. This is because, although you can get iron from foods such as pulses, green leafy vegetables and nuts, the iron in these foods isn't absorbed so easily. The symptoms of this feeling breathless after little exercise, feeling tired and a short attention span and poor concentration. These symptoms could negatively affect proficiency in school and the ability to perform well at work ultimately leading to a loss of productivity which has both personal effects and broader effects for the economy. Other conditions include frequently becoming ill, frequently becoming depressed, and malnourishment.
The problems with fatigue, apathetic behaviour and concentration are mostly a result from a lack of iron in the diet. However as with any diet this is only a problem when not eating the right things, this regularly means that such iron deficiency can be a problem in the developing world where vegetarians have little choice – usually eating little else except what they grow, normally just cereals. “Although the iron stores of vegetarians are sometimes reduced, the incidence of iron-deficiency anaemia in vegetarians is not significantly different from that in the general population”, there are plenty of sources of iron that can be eaten by vegetarians such as legumes and whole grains that are a substantial part of most western vegetarian’s diets meaning it is not a problem. Research done in Australia concludes that "There was no significant difference between mean daily iron intakes of vegetarians and omnivores".
It is natural for human beings to farm, kill, and eat other species. In the wild there is a brutal struggle for existence as is shown by Darwin’s On the Origin of the Species. The fact that we humans have succeeded in that struggle by exploiting our natural environment means that we have a natural right over lower species. The concept of survival of the fittest may seem outdated but it is still the defining order of nature. In fact farming animals is much less brutal than the pain and hardship that animals inflict on each other naturally in the wild.
To suggest that battery farms are in some way 'natural' is absurd - they are unnatural and cruel. To eat meat is to perpetuate animal suffering on a huge scale - a larger, crueler, and more systematic scale than anything found in the wild. Furthermore, the very fact of humanity's 'superiority' over other animals means they have the reason and moral instinct to stop exploiting other species. If an alien species from another planet, much more intelligent and powerful than humans, came and colonized the earth and farmed (and force-fed) human beings in battery farm conditions we would think it was morally abhorrent. If this would be wrong, then is it not wrong for we 'superior' humans to farm 'lower' species on earth simply because of our ability to do so?
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