Grain for feed if diverted to food could feed more than 3.5 billion people by 2050
By 2050, 1,573 million tonnes of cereals will be used annually for non-food (FAO, 2006a), of which at least 1.45 million tonnes can be estimated to be used as animal feed. Each tonne of cereal can be modestly estimated to contain 3 million kcal. This means that the yearly use of cereals for non-food use represents 4,350 billion kcal. If we assume that the daily calorie need is 3,000 kcal, this will translate into about 1 million kcal/year needed per person. From a calorie perspective, the non-food use of cereals is thus enough to cover the calorie need for about 4.35 billion people. It would be more correct to adjust for the energy value of the animal products. If we assume that all non-food use is for food producing animals, and we assume that 3 kg of cereals are used per kilogram animal product (FAO, 2006b) and each kilogram of animal product contains half the calories as in one kg cereals (roughly 1,500 kcal per kg meat), this means that each kilogram of cereals used for feed will give 500 kcal for human consumption. One tonne cereals used for feed will give 0.5 million kcal, and the total calorie production from feed grains will thus be 787 billion kcal. Subtracting this from the 4,350 billion calorie value of feed cereals gives 3,563 billion calories. Thus, taking the energy value of the meat produced into consideration, the loss of calories by feeding the cereals to animals instead of using the cereals directly as human food represents the annual calorie need for more than 3.5 billion people.