The forests that once covered the planet and were the cradle of our species are growing ever sparser. Biodiversity is also experiencing an inexorable decline, global wildlife has decreased by 58 per cent from 1970 to 2012, and over the past forty-five years the quantity of fish in our oceans has halved. The correlation between the environmental devastation the planet is experiencing and our diet is now plain to see — we can no longer ignore it.

Eating the earth

The book "Mangiare la terra. Etica ambientale e scelte alimentari", written by Lisa Kemmerer, professor of philosophy of religions at Montana State University, is dedicated precisely to the connection between everyday dietary choices and environmental degradation. The scholar has produced a work that highlights the enormous environmental impact of livestock farming, fishing and hunting on ecosystems around the world.

The power of consumers

The author reminds consumers of the considerable power they hold, arguing that the daily choice of what we put on the table has concrete effects on the environment, and that through careful choices we can help prevent deforestation, pollution, and the depletion of soils and seas. "As consumers […] with your wallet you vote for or against the earth," the book reads. "Committing to a plant-based diet is the most important decision you can make in the name of the environment. You can decide which side you are on every time you sit down to eat."

The impact of livestock farming

In the book, Lisa Kemmerer makes extensive use of data to support her argument, noting for example that a serving of beef creates a global warming potential equivalent to 36 kilograms of carbon dioxide. Even more significant is the figure relating to agricultural products destined to feed livestock: 70 per cent of United States grain and 60 per cent of European grain is used to feed farmed animals.

The leading cause of climate change

The consumption of animal products, according to the author, produces ten times more fossil fuel emissions per calorie than the direct consumption of plant-based foods. Kemmerer refers to the Livestock's Long Shadow report, published in 2008 by the United Nations. The study identifies animal farming as the primary cause of climate change, though Kemmerer charges the report's authors with having stepped back from the obvious conclusions: "if we intend to protect the environment, we must stop producing and consuming animals and animal products."

There is no such thing as cheap animal products

"Low-cost meat, dairy and eggs are an illusion," Kemmerer stresses; the rock-bottom prices at which such foods are sold do not account for the externalised costs borne by the community as a whole. "We pay for each of them with depleted forests, polluted freshwater, soil degradation and climate change. Diet is the most important decision we make regarding our environmental impact."

The silence of environmentalists

Environmentalists, the author also notes, tend to be inexplicably silent on the subject of dietary choices. "Rather than altering meal plans, and asking others to do the same, environmentalists have preferred to urge us to use less water on our lawns and in the shower, to choose fuel-efficient cars and fluorescent light bulbs. While these are important measures, each of them is irrelevant when compared to the environmental benefits of switching to a vegan diet."

Oceans of death

The book also highlights the enormous impact of the fishing industry: industrial fishing is gradually emptying seas and oceans around the world and is based on an unsustainable model. In 2003, the Pew Ocean Commission reported the alarming decline of large marine predators: "we have removed a quantity equal to 90 per cent of large predators such as sharks, swordfish and cod from the world's oceans." A perverse effect of this type of fishing is what is known as "bycatch" — a term for those marine creatures caught by mistake, though as Jonathan Safran Foer reminds us, "it's not really by mistake because bycatch is a constituent part of contemporary fishing methods that generate abnormal catches with abnormal quantities of bycatch." The seemingly endless list of bycatch includes seabirds, turtles, whales, dolphins and seals. There is, however, a way to avoid contributing to the depletion of marine and terrestrial ecosystems: choosing to eat something else.