The havoc caused to the world environment by the billions of animals we raise and kill for food each year is huge. The U.N. has identified the animal industries as 'one of the most significant contributors to today's most serious environmental problems', including global warming, loss of fresh water, rainforest destruction, spreading deserts, air and water pollution, acid rain, soil erosion and loss of habitat. Vast areas of forest are cleared to grow crops to feed farmed animals. The methane produced by these animals is the largest single cause of global warming, larger than all transport worldwide. Large quantities of excrement produced by animal industries leak into rivers and oceans as pollution.
Instead of growing crops to feed animals who we then eat, it would be much more efficient and cause less harm to the environment if we consumed the plants directly. This would feed five times as many people, make available significant amounts of fresh water, help reverse global warming, use less fossil fuels and allow large areas of land to be reforested.
"Producing meat turns vegetable protein very inefficiently into animal protein, using large amounts of energy and water in the process. Ruminant animals also produce large amounts of methane, a much more potent greenhouse gas than carbon dioxide. Meat production is a serious contribution to greenhouse gas pollution and hence global warming."
- Professor Ian Lowe
Most people today recognise the importance of considering the environment in their daily lives, by saving water and energy, driving more fuel efficient cars and using renewable energy. However, one of the simplest and yet most significant choices we can make to reduce our environmental impact is to switch to a vegan diet.
- Water use from food consumption makes up 90% of the average Australian's water use. Vegans use less than a third of the water of the average Australian. 
- 67% of water in Australia is used for agriculture whereas only a mere 9% is used for household use. 
- In Australia, 43% of agricultural water is used for pasture and hay production for grazing animals who are raised for the meat and dairy industry. In comparison only 10% is used for the production of fruit and vegetables for human consumption. 
- It takes 20 times more water to produce a kilo of beef (between 50,000 and 100,000 litres) than it does rice (about 2,500 litres), fruit or veg. 
- On Average it takes 800 litres of water to produce one litre of dairy milk, almost 4 times as much as it takes to make one litre of soy milk. 
- The worlds cattle consume enough food to feed 8.7 billion people, more than the entire human population. 
- According to the CSIRO and University of Queensland a massive 92% of all land degradation in Australia is caused by animal agriculture. 
- Over a twenty year time-frame, 49% of Australia's greenhouse gas emissions and over 50% of worldwide emissions can be attributed to animal agriculture. 
- Animal agriculture consumes more protein and calories than it produces. 
- Animal agriculture is the leading cause of global species loss. 
- A vegan diet uses substantially less energy than a diet based on animal products and therefore contributes much less to air pollution, acidification, oil spills, habitat destruction and global warming. 
- By choosing to live vegan, you will help not only the environment but all the animals who inhabit the earth.
 Professor Wayne Meyer, C.f.I.F., Water for Food - The continuing debate. 1998.
 Spencer, C., The Heretic's Feast: A History of Vegetarianism. 1995.
 http://bze.org.au/landuse and http://ijc.cgpublisher.com/product/pub.185/prod.269