FAO projects that world population will increase 34 - 41% and reach 8.9 - 9.1 billion by 2050, food demand will increase by 70%, and daily per capita calorie intake will rise to 3,130 calories. Food is a major part of climate change, but it is also essential for survival, security and equity.
Worldwide, 2 billion people live primarily on an animal-based diet, while 4 billion live primarily on a plant-based diet. In fact, the UNEP estimated that calories lost from feeding cereals to animals could feed an extra 3.5 billion people.i
Another study found that 4 billion could be fed on with the crops devoted to livestock. The researchers found that the single biggest intervention to free up calories would be to stop using grains for cow carcass production in the US. The US, China and Western Europe account for the bulk of the 'diet gap,' and corn was the main crop being diverted to animal feed.ii
The UN World Health Organization (WHO) estimated that the number of people fed in a year per hectare ranged from 22 for potatoes and 19 for rice, to 1 and 2, respectively, for cow and sheep carcass. It added that the low energy conversion ratio from feed to carcass is a concern, since some of the cereal grain food produced is diverted to livestock production.iii
i Global Agriculture 2014
ii West et al 2014