Meat vs Veg: An Energy Perspective


By Eric Garza, PhD

March 22, 2014

What ought we eat? This is among the preeminent questions of our time, one asked by policy wonks, diet gurus and, of course, consumers. People imbue a wide array of values into their dietary choices, including impacts on their health, cost and environmental impacts, among others. The question of what to eat generates a particularly generous array of fireworks when it pits plant eaters – vegans and vegetarians – against consumers of animal flesh.

I’ve spent time as both a vegan and vegetarian, adopting both practices due to ethical concerns regarding how meat is raised in the United States. As I’ve learned about the array of management practices available to animal farmers I’ve opened to eating animal-derived foods again, and have also taken up hunting. Beyond this, I do life cycle energy audits within the agricultural sector as part of my profession, and I’ve accumulated enough data to see a fascinating story emerge regarding one particular impact of food production: its energy intensity. In this essay I’ll present data on the energy intensity of animal- and plant-derived foods and hopefully contribute to a constructive dialog about what we ought to eat and how we ought to be producing it.


Modern food systems turn industrial fuels into food. As I pointed out in my essay on the energy basis of food security, high and volatile energy prices inspire many to wonder how much longer we can afford to depend on this industrial model, and perhaps a time is coming when economic forces will favor a different one. While I’d never claim that energy input/output figures should singularly drive food system design considerations, the preeminence of energy throughput to industrial society suggests to me that energy efficiency should certainly be an important factor.

Vegetables and fruit are obviously a necessary component of a healthy human diet, contributing calories as well as a wide array of plant secondary compounds with nutritional and medicinal benefits. Animal foods also contribute by offering complete protein and necessary fatty acids, at least when pasture raised in a way that affords animals access to a diverse, natural diet. As the debate continues on the role that animal-derived foods can and should play in our food system, I hope that the data I’ve presented here injects clarity into discussions that focus on the energy efficiency of these two classes of foods. Vegetables and fruits are not inherently less energy intensive, and pastured meats are not necessarily more so. I look forwards to gathering additional data on this subject, and making it available to aid others in developing management practices that yield resilient and profitable agricultural systems.

(click here to read the full article by Eric Garza)