Diet for a low-carbon planet

Most of the proposed solutions to climate change such as substitution of fossil fuels require large investments, policies that are politically contentious or difficult to enforce, and years to fully implement. However, some of the most effective and lowest cost opportunities for greenhouse gas (GHG) reductions are lifestyle choices that can be made today that cost little, and that are actually good for us. Chief among them is the decision to adopt a healthier, less meat intensive diet.

The significance of this opportunity was emphasized in a recent presentation at the World Bank by Jonathan Foley, director of the University of Minnesota Institute on the Environment. According to analysis by the Institute, every pound of meat is equivalent to about 30 pounds of grain production in its contribution to climate change when allowance is made for the full life cycle of livestock production. This is primarily because methane emissions from ruminants have a GHG impact roughly 25 times that of carbon dioxide.

Another expression of the resource intensity of meat production, Foley explained, is that even highly efficient agricultural systems like that in the US only deliver about the same calories per hectare in human consumption terms as poor African countries with more grain based diets. The surprisingly large role of livestock in global warming was explored in a 2009 article by Robert Goodland, formerly a World Bank economist, and Jeff Anhang, an IFC environmental specialist. They estimate that when land use and respiration are taken into account and methane effects are properly calculated, livestock could account for half of current warming when using a 20 year time-frame. According to Goodland and Anhang, replacing 25% of livestock products with alternatives would liberate as much as 40% of current world grain production with comparable benefits in reduced burdens on land, water, and other resources.