Tag Archives: Sustainability

Vegetarianism: Key to Coping with Population Growth?


A post from French newspaper Le Monde‘s “Éco(lo)” blog speculates that an increase in the global number of vegetarians may help conserve water as the world adds an estimated 2 billion more people by 2050.  I’ll quote a bit of it for any Francophone readers out there:

Si les pays développés connaissent l’urgence à réduire la consommation de viande, peu imaginent adopter dans les prochaines décennies un régime végétarien quasi-généralisé. C’est pourtant la réalité qui attend la population mondiale d’ici 2050 afin d’éviter des pénuries alimentaires catastrophiques et des déficits en eau considérables, si l’on en croit une étude du Stockholm International Water Institute, citée par le Guardian.

Aujourd’hui, à l’échelle de la Terre, les 7 milliards d’hommes tirent en moyenne 20 % de leurs apports en protéines de produits d’origine animale. Mais d’ici 2050, ce chiffre devrait tomber à 5 %, pour nourrir deux milliards d’êtres humains supplémentaires.


La production de viande nécessite en effet non seulement de l’espace et des ressources – 30 % des terres habitables de la planète sont utilisées pour nourrir les animaux, selon l’Organisation des Nations unies pour l’alimentation et l’agriculture(FAO) –, mais aussi beaucoup d’eau pour faire pousser les cultures destinées à l’alimentation du bétail. Selon l’étude, les régimes riches en protéines animales engloutissent cinq à dix fois plus d’eau que ceux végétariens. Un kilo de bœuf nécessite ainsi 15 500 litres d’eau, un kilo de porc, 4 900 litres, le poulet, 4 000 litres, et le riz, 3 000 litres, selon une autre étude parue en février. Or, 1,1 milliard de personnes n’ont actuellement pas accès à une source d’eau salubre, selon l’organisation mondiale de la santé, et 800 millions à l’eau potable, d’après les Nations unies.

D’après les scientifiques, le végétarisme serait donc une façon d’augmenter la quantité de ressources naturelles disponibles pour produire plus de nourriture.

Basically, this post is reporting on a recent study by the Stockholm International Water Institute that estimates that global water supplies will be insufficient to produce enough meat to feed all the people on earth by 2050.  Because of the amount of water required to hydrate and produce feed for livestock, vegetarian diets are estimated to necessitate 5-10 times less water than the diets of meat-eaters.  The post claims that today, worldwide, 20% of people’s protein sources come from meat but that this number must drop to 5% for everyone to get enough protein.  If more people became vegetarian, this sort of outcome might be achieved, although there is one caveat (my translation follows):

The question of vegetarianism is not, however, clear-cut.  Certain experts estimate that vegetarians in developed countries do not consume many fewer resources than moderate omnivores.  The World Wildlife Fund also released in 2010 a report on the impact of agricultural production that emphasized that meat substitutes, including foods made from imported soy, could actually use more cultivatable land than their meat or dairy counterparts.

Which doesn’t negate the main point but merely emphasizes the importance of doing vegetarianism “the right way,” so to speak.  I’m a vegetarian–I eat no meat, including seafood, though I still eat eggs and dairy–so this sort of change appeals to me.  The blog post points out some of the ecological benefits of agriculture geared toward vegetarian diets, and, without getting into them, I think there would be health and ethical advantages as well.  (I must admit that while I feel I’ve done enough research to justify my personal decision not to eat meat, I’d need to do more to have an informed opinion about the probable ecological impacts of shifting global agriculture away from meat production.)

The problem, as I see it, is that such a shift toward increased vegetarianism wouldn’t be automatic.  The post also describes the number of people living in great hunger or famine conditions today, and I suspect that if this study’s model is accurate, a decrease in the availability of meat protein would lead to greater hunger and malnourishment rather than an uptick in vegetarianism.  The latter change would require a global, concerted effort, which would be most effective if led by governments around the world.  That seems decidedly unlikely.  There have been Malthusians since Malthus, and they’ve been wrong so far, but this sort of study still makes me worry.

Image by Corey Templeton