The consumption of animal flesh (whether meat, fowl or fish) or the use of animal products (leather goods, products of bone-processing, eggs and cheese) is unethical, unaesthetic, uneconomic, and without nutritional justification. It may be considered unethical because human beings should not needlessly kill sentient animals. The consumption of animal flesh is not the most economic method of obtaining the highest yield of nutritional products from agricultural land. The economic and social costs of meat consumption include hugely inefficient use of freshwater and land, heavy pollution from livestock faeces, rising rates of heart disease and other degenerative illnesses and spreading destruction of forests.
Between 1950 and 2000, per capita consumption of meat around the globe more than doubled. A European study has shown that regular meat eaters are more likely to become fat. In China, a recent shift to meat-heavy diets has been linked to increases in obesity, cardiovascular disease, breast cancer and colorectal cancer. It is not fully understood what are the health implications for people who eat the flesh of animals that have been fed on genetically modified food, hormones and antibiotics.
In the USA, the number of animals slaughtered annually for food is estimated at between 4.5 and 6 billion. In 1989, the average person in the USA consumed just under 100 kg of meat annually. Calculated in whole lives, both human and animal, an average North American family consumes: 12 cattle, 1 calf, 2 lambs, 29 pigs, 984 chickens, and 37 turkeys. In the UK in 1987 the number included: 4 million cattle, 60,000 calves, 13.5 million sheep, and over 15 million pigs.
90% of land in Europe and America is used to raise fodder for animals; this area is 14 times more than that required to supply a vegetarian diet of the same protein and calorific value. At least eight vegetarians could be fed with the same quantity of grain as is required to produce stock feed for one average meat-eating person. Then there is the water consumption. To produce 1 kg of feedlot beef requires 7 kg of feed grain, which takes 7,000 kg of water to grow. In the USA, 70 percent of all the wheat, corn and other grain produced feeds livestock.
In recent years, livestock waste has been implicated in massive fish kills and outbreaks of such diseases as pfiesteria, which causes memory loss, confusion and acute skin burning in people exposed to contaminated water. In the USA, livestock now produce 130 times as much waste as people do. Just one pig farm in Utah, for example, produces more sewage that the city of Los Angeles.