The growing global human population and the increased global wealth will result in the consumption of billions more animals each year.

The so-called “developing” world is growing quickly and in most cases adopting Western lifestyles and diets as they do so. Feeding a global population of more than 9.3 billion (by 2050) will therefore mean the consumption of billions more animals. With references to Thomas Malthus and a recent study by David and Marcia Pimentel, we take a closer look at this population problem.

In 1798, the mathematician Thomas Malthus wrote, “Population, when unchecked, increases in a geometrical ratio. Subsistence increases only in an arithmetical ratio.” More specifically, the Malthusian Dilemma refers to “a return to subsistence-level conditions as a result of population growth outpacing agricultural production.” In other words, the scarcity of critical resources, particularly food and water, will knock human civilization back to a state of subsistence (minimum life support). This is due primarily to population growth, if left unchecked.

Malthus would undoubtedly agree with an item in our research library. The item is a study called “Sustainability of Meat-Based and Plant-Based Diets and the Environment,” written by David and Marcia Pimentel of Cornell University in 2003. The Pimentels provide an objective (and rather bleak) view of the future of food scarcity. While they find that a meat-based diet is clearly less sustainable than a vegetarian diet, the real culprit when it comes to sustainability is population growth.

According to the study:

Worldwide, an estimated 2 billion people live primarily on a meat-based diet, while an estimated 4 billion live primarily on a plant-based diet. The US food production system uses about 50% of the total US land area, 80% of the fresh water, and 17% of the fossil energy used in the country. The heavy dependence on fossil energy suggests that the US food system, whether meat-based or plant-based, is not sustainable. [And later…] However, the meat-based diet requires more energy, land, and water resources than the lactoovovegetarian diet. In this limited sense, the lactoovovegetarian diet is more sustainable than the average American meat-based diet.

Using these results (which, quite frankly, are consistent with common sense), farm animal advocates can claim sustainability among the many benefits for vegetarian (and vegan) diets. Raising animals for food requires more grain than feeding people directly, and therefore it is an inefficient and unsustainable use of both land and water. From an exclusively sustainability standpoint, however, everyone becoming vegetarian will not be enough; we must also control our population growth. At 6.7 billion, humans are already arguably living beyond the Earth’s carrying capacity. According to the Pimentels:

The major threat to future survival and to US natural resources is rapid population growth. The US population of 285 million is projected to double to 570 million in the next 70 (years), which will place greater stress on the already-limited supply of energy, land, and water resources. These vital resources will have to be divided among ever greater numbers of people.

Some animal groups have estimated that the average American consumes about 2,600 animals in his or her lifetime. As animal advocates, it could well be that our most effective form of activism would be to keep some of those average Americans from being born; i.e., focus on population control. In vitro meat production, which I have advocated, would eliminate 98% of animal suffering. But if we are to save the planet and ensure survival of its many species (including our own), the solution must inevitably involve controlling – and reducing – the human population.