It is often estimated that a third to a half of the food produced for human consumption globally is lost or wasted. But an even bigger waste, which is not included in this estimate, may be through what researchers at the Weizmann Institute of Science in Israel have called “opportunity food costs” – dietary choices that result in the squandering of environmental resources.

Opportunity food loss mainly comes from using agricultural land to produce animal-based food instead of nutritionally equivalent plant-based alternatives. The researchers estimate that, in the United States alone, replacing animal-based food with edible crops having the same nutritional value would provide enough food for more than double the U.S. population.

For example, the land area that could produce 100 grams of protein from soya, potatoes, cane sugar, peanuts and garlic would yield only 4 grams of edible protein if used to produce beef.

The amount of additional food that could be produced by growing crops rather than animal-based foods is estimated to be:

  • beef – 25 times as much
  • pork – 10 times as much
  • diary – 4 times as much
  • poultry – twice as much
  • eggs – 1.7 times as much.

In a similar vein, Anas Ghadouani, a professor of environmental engineering at the University of Western Australia has pointed out that the amount of water used to produce chocolate – 24,000 litres of water for each kilogram of chocolate – far exceeds that for any other food product. In comparison, one kilogram of beef requires the still enormous amount of 15,000 litres of water.