Vegetarian Diets: How Sustainable?
Barbara Sheppard. Urban Ecology Australia. 2004.5
In the article ‘Think, Feel, Create, Design, Feast, Play’ (Newsletter 49), reporting on the Sustainable Living Festival held in Melbourne, the statement is made that ‘vegetarian and vegan food[s] [are] the only truly sustainable foods’. This is a commonly held belief, but I wonder whether there is any real evidence to support it.
Much of the argument in favour of vegetarian diets stems from an opposition to factory farms that produce meat from animals kept in appalling conditions and fed an unnatural diet. I certainly don’t think that such practices should be supported. There is, however, a lot of land on the Earth that cannot be used for growing crops, but that can support grazing or foraging animals very well. If we decided to dismiss these as a source of food and persuaded everyone on Earth to become a vegetarian, we would be reducing the amount of land that is available for producing food for humans, and thus putting even greater pressure on the existing cropland. Besides, the monocultural practices involved in much of modern agriculture are responsible for a lot of environmental damage and are certainly not sustainable.
This is particularly true for Australia. According to Dr Tim Flannery, we lose seven kilograms of soil for every kilogram of wheat we grow, whereas kangaroos can roam the country without damaging the soil and can be harvested sustainably to provide us with meat. Thus, it makes sense to include free-ranging animals in a varied omnivorous diet, as long as the numbers harvested are not so great that the species become endangered. It is also useful to consider sources of animal protein that are not commonly consumed in our culture, such as insects. Instead of trying to eliminate ‘plagues’ of locusts by spraying them with pesticides, perhaps we should be looking for ways to harvest them as food.
There is much idealism in the vegetarian movement that deplores the killing of animals for any reason at all, or, in the case of vegans, even the use of foods derived from live animals. It may seem unsavoury to think about in our present-day ‘civilised’ culture, but the fact is that animal foods have played a significant role in the human diet over a long period of our evolutionary history. It may not be wise to scorn the diet of our ancestors and expect to remain healthy as a species. Many people experience severe health problems when eating diets that rely heavily on such vegetarian staples as cereal grains and legumes, and any serious discussion of sustainability must surely include human health as an important factor.
While it is true that human civilisation would not have reached its present level without the advent of agriculture and the mass cultivation of crops, I think it is unlikely that a human diet consisting only of vegetarian and vegan foods would turn out to be truly sustainable.
References
Byrnes, Stephen (2002), The Myths of Vegetarianism
Cordain, Loren (1999), Cereal Grains: Humanity’s Double-Edged Sword PDF
Flannery, Tim (1998), The Future Eaters: Eating the Future — The Last 200 Years
Groves, Barry (2002), The Naïve Vegetarian
2007.2.8