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Our Future Depends On Our Food Choices

By: Richard Schwartz, Ph.D.
(reprinted at with his permission)

There are many reasons for people to consider becoming vegetarians, including concerns for their health, animals, and the environment. This article considers why a major societal shift to plant-based (vegan) diets is essential to avoid impending climate, environmental, food, energy, and water crises.

Climate Change

There are increasing indications that the world is rapidly approaching an unprecedented climate catastrophe. This is the view of science academies worldwide and of over 97 percent of climate scientists.

The 12 warmest years since temperature records have been kept in 1880 have occurred since 1998. Every decade since the 1970s has been warmer than the previous decade. Glaciers and polar ice sheets are melting far faster than the projections of climate scientists. There has been a major recent increase in the number and severity of severe climate events, including heat waves, droughts, wildfires, storms and floods.

While many people are in denial about climate change, there is a very strong scientific consensus that climate change is happening, that it poses a major threat to humanity and that human activities are the primary cause, as indicated by many peer-reviewed articles in respected science journals and statements by science academies all over the world.

Many climate experts, including James Hansen, director of the National Aeronautics and Space Administration (NASA) Goddard Institute for Space Studies, believe that a safe upper limit for carbon dioxide in the atmosphere is 350 parts per million (ppm). Atmospheric CO2 recently reached 400 ppm and it has been growing by 2 – 3 ppm per year, making climate experts very concerned.

What has Hansen and other climate scientists especially worried is that climate change could soon reach a tipping point, unleashing a vicious cycle of rapid climate change leading to disastrous consequences – melted sea caps, flooded cities, mass species extinctions and spreading deserts, among other events – unless major changes in how humanity uses energy soon occur.

How a Shift to Vegan Diets Can Combat Climate Change

It may seem naïve to argue that a mere change of diet could be a potent prescription for combating climate change, but the evidence is incontrovertible, and slowly the public is getting the message.

Much of global warming discussions by governments, environmental groups and individuals over the past 20 years has focused on implementing changes in energy use and given little attention to the impact of our diets. This trend changed somewhat upon publication of a landmark 2006 report by the United Nations Food and Agricultural Organization (FAO), estimating that livestock production globally is responsible for more greenhouse gas emissions (GHGs, in CO2 equivalents) than is emitted from all of the world’s cars, planes, ships, and all other means of transportation combined.

The FAO report, Livestock’s Long Shadow, also projected that the world’s current annual consumption of about 60 billion land-based animals will double by mid-century if current human population growth and dietary trends continue.

The resulting increase in GHGs would largely negate reduced GHG emissions from conservation and improved efficiencies in transportation, electricity and other sectors, making it extremely difficult, if not impossible, to reach the GHG reductions that climate experts believe essential to avoid a climate disaster. While that doubling may not occur, it is troubling that in the face of livestock’s strong role in warming the planet, many countries are encouraging the expanded consumption of animal products.

More recently, an in-depth analysis, “Livestock and Climate Change,” by World Bank Group environmental specialists Robert Goodland and Jeff Anhang was published in the November/December 2009 issue of World Watch magazine. The authors argue that there are sources of GHGs from the livestock sector that were overlooked, underrepresented or placed in the wrong sectors in the FAO report, and concluded that the livestock sector is responsible for at least 51 percent of all human-induced GHGs.

Goodland and Anhang call for the replacement of livestock products with plant-based alternatives, based on the rationale that this would result in quick reductions in atmospheric GHGs, while also reversing on-going world food and water crises.

Leading climate specialists have focused increasingly on the role of food in global warming, pointing out that there is no more powerful environmental action that any individual can take than adopting a plant-based diet.

Environmental Crises

The raising of 60 billion farm animals for slaughter worldwide annually is creating many environmental threats. These include deforestation, desertification, rapid species extinction, air and water pollution, and many more.

How a Shift to Vegan Diets Can Reduce Environmental Crises 

Modern agricultural methods used in meat production are a prime cause of the environmental crises facing the United States and much of the rest of the world today. Some examples include:

  • Over 85 percent of soil erosion is caused by animal grazing and feed lot food production.

  • Cattle production is a prime contributor to every one of the causes of desertification: overgrazing of livestock, over-cultivation of land, improper irrigation techniques, deforestation, and prevention of reforestation.

  • Mountains of manure produced by cattle raised in feedlots wash into and pollute streams, rivers, and underground water sources.

  • The tremendous amount of grain grown to feed animals requires extensive use of chemical fertilizer and pesticides, which cause air and water pollution. Various constituents of fertilizer, particularly nitrogen, are washed into surface waters. High levels of nitrates in drinking water cause illnesses to people, as well as animals.

  • Demand for meat in wealthy countries leads to environmental damage in poor countries. Largely to turn beef into fast-food hamburgers for export to the U.S., the earth’s tropical rain forests are being bulldozed at a rate of a football field per second. Each imported quarter-pound fast-food hamburger patty requires the destruction of 55 square feet of tropical forest for grazing.

Food Shortages


We appear to be at the start of major food shortages that have great potential to worsen. Prices for grain have risen to record levels recently. One reason is the effects of climate change. For example, a tremendous heat wave in Russia – temperatures in July 2010 averaged 14 degrees Fahrenheit above the norm – caused a loss of almost 40 percent of the Russian wheat crop. Recent droughts in China, major parts of the United States, and other countries could cause another major spike in grain prices.

Already, nearly a billion of the world’s people are chronically hungry and an estimated 20 million people die annually worldwide due to hunger and its effects.

Unfortunately, meeting the food needs of the world’s people will become increasingly difficult, Demand is expected to increase because of rising population, the movement of many people up the food chain, eating more animal products that require the consumption of grain for their production, and the increasing use of corn for ethanol.

And the production of grain is likely to decline because of the effects of climate change – droughts, floods, crop withering heat waves, melting glaciers, and shrinking aquifers – and by the conversion of farmland to other uses. The contamination of food by radiation from the Japanese nuclear power plants damaged by the recent powerful earthquake and tsunami will make the situation even worse.

How a Shift to Vegan Diets Can Reduce World Hunger

A shift to vegetarian diets can help greatly reduce world hunger. Consider these statistics:

  • While the average Asian consumes between 300 and 400 pounds of grain a year, the average middle-class American consumes over 2,000 pounds of grain, 80 percent of which comes in the form of meat from grain-fed animals.

  • While one hectare (about 2.5 acres) of land growing potatoes can feed 22 people, and one hectare growing rice can feed 19 people, that same area producing beef can feed only one person.

  • Making the situation even more scandalous, feeding grain to livestock wastes 90% of the protein, 99% of the carbohydrates, and 100% of the fiber of the grain, and produces a product that is high in cholesterol and saturated fat.

Energy Shortages

There are also many problems related to the world’s ability to produce enough energy to meet future needs. Many experts believe think we may soon reach a time of peak oil, when oil production will start to decline. The recent nuclear disasters in Japan caused by the major earthquake and tsunami show the dangers of relying on nuclear power. And coal-burning power plants are a major source of greenhouse gases. It is essential that there soon be a major increase in the production of renewable sources of energy as well as major efforts to reduce the demand for energy.

How a Shift to Vegan Diets Can Save Energy

Animal-based diets waste much energy. In the United States, an average of 10 calories of fuel energy is required for every calorie of food energy produced; many other countries obtain 20 or more calories of food energy per calorie of fuel energy. To produce one pound of steak (500 calories of food energy) requires 20,000 calories of fossil fuels, most of which is expended in producing and providing feed crops.

It requires 78 calories of fossil fuel for each calorie of protein obtained from feedlot-produced beef, but only 2 calories of fossil fuel to produce a calorie of protein from soybeans. Grains and beans require only two to five percent as much fossil fuel as beef. The energy needed to produce a pound of grain-fed beef is equivalent to one gallon of gasoline.

Water Shortages

The world is also experiencing increasing water shortages. As mentioned above, climate change is causing severe droughts in many parts of the world. Some experts are predicting that our time will be called, “The century of drought.”

Trying to grow adequate food for the world’s people through irrigation is causing aquifers to shrink in many countries, and some may soon be depleted. In addition, glaciers that provide replenishment water to rivers in the spring are receding rapidly. Already about one-sixth of the world’s people lack access to safe drinking water. And the worldwide demand for water is projected to double within 20 years.

How a Shift to Vegan Diets Can Reduce Water Scarcity

The standard diet of a meat-eater in the United States requires 4,200 gallons of water per day (for irrigation of feed crops, animals’ drinking water, meat processing, washing, cooking, etc.) A person on a purely vegetarian (vegan) diet requires only 300 gallons per day. Animal agriculture is the major consumer of water in the U.S.

According to Norman Myers, author of “Gaia: An Atlas of Planet Management,” irrigation, primarily to grow crops for animals, uses over 80 percent of U.S. water. Almost 90 percent of the fresh water consumed annually in the U.S. goes to agriculture, according to agriculture expert David Pimentel.

The production of only one pound of edible beef in a semi-arid area such as California requires as much as 5,200 gallons of water, as contrasted with only 25 gallons or less to produce an edible pound of tomatoes, lettuce, potatoes, or wheat. Newsweek reported in 1988 that, “the water that goes into a 1,000 pound steer would float a [naval] destroyer.”

Security Concerns Related to the Above Crises

Many military leaders and security experts are increasingly concerned about the national security implications of climate change and the other threats discussed above. In 2007, eleven retired United States generals and admirals issued a report indicating that millions of hungry, thirsty, desperate refugees fleeing from droughts, floods, heat waves, storms, wildfires and other effects of climate change will make instability, violence, terrorism and war more likely. Military and intelligence strategists in many countries are revising their planning to take climate change effects into account.


When we consider all of these negative environmental and climate-change effects, and then add the harmful effects of animal-based diets on human health, it is clear that animal-centered diets and the livestock agriculture needed to sustain them pose tremendous threats to global survival.

It is clear that a major societal shift toward veganism is imperative to move our precious but imperiled planet away from its present catastrophic path and onto a sustainable path.

NOTE: This article was written by Richard Schwartz, Ph.D. and appears here at with his permission.

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