Instead, in order to keep up with consumer demand, livestock producers have adopted intensive farming techniques, such as swine confinement operations and cattle feedlots, that rely on grains and legumes to feed the animals, thus using cropland, fertilizers, and water. Other farmers have increased land use for grazing and growing animal feed to meet increased demand, resulting in deforestation and erosion. These trends in animal agriculture are pushing our natural systems to their limits. The quality of our land, water, and air is being degraded, valuable resources are diminishing, and biodiversity is rapidly being lost. Although any food choice will put some pressure on the environment, choosing a vegetarian diet can decrease your impact tremendously.
Vegetarian diets use as little as one quarter the resources required to produce animal food.
Limiting animal products in the diet is the single most important thing a consumer can do to help the environment, dwarfing the impact of such things as recycling, and even transportation choices. The biggest environmental problem with using cropland to grow food for food animals that we will eventually eat is that it is not very efficient. Even with intensive farming where animals are confined, bred, and drugged to make production more efficient, we lose most of what we feed to animals. Roughly speaking, farm-raised animal foods use about five times as much land, water, energy, pesticides, and other petrochemicals as the equivalent amount of plant food for human consumption. The biggest issue is land.