There is no competition for food between livestock and people
Livestock feed is often presented as competing with human food. But according to FAO, 86% of livestock feed is not suitable for human consumption. It is often reported that 6-20kg of cereals are required to produce 1kg of beef. These figures certainly do not apply in the case of Europe, and the calculation is incorrect even at a global level. For example, the EU ruminant production system is based on grazing and mixed systems.
Grasslands play a significant role as fodder to feed livestock, converting grass into highly nutritious food. Also, concentrated feed given to livestock is composed of crop residues and by-products of cereals (from milling starch factory, distillery), protein crops (pea co-products), oilseed (oilcake rapeseed, sunflower), fruit (pulp citrus), vegetables and tubers (pulp beet, potato) as well as milk (whey from cheese factories).
Therefore, the ratio of human-edible food in ruminants grazing and mixed systems is extremely low. At a global level, human-edible feed materials represent about 14% of the global livestock feed ratio. A recent study by some researchers of the Friedman School of Nutrition Science and Policy in Elementa magazine – Science of the Anthropocene showed how comparing ten different diets, the more vegan oriented shows a worse and less differentiated use of the “resource soil”.
Ten very different diets represent ten ways to influence the environment, ten ways to influence our natural life, world biodiversity and cultural heritage such as the landscape. Among the ten diets, those excluding animal-origin food, generally believed more “virtuous”, have been revealed to be less efficient in land management, focusing only on arable land exploitation.
Indeed, in a paradoxical scenario made of 100% vegans, we would need more arable land than currently, as ingredients of the vegan diet are produced with very low efficiency in grazing lands. Not all agricultural lands are comparable in terms of theoretical productivity: some of them, for example, give their best with cereals, but they are inefficient for fruit and vegetable production, such as clayey soils poor in water resources.
On the other hand, some lands are only suitable for pasture as vegetable cultures would represent a too-high energy factor choice (stones density, soil depth, slope incidence, etc.). According to the results, land use connected to a vegan diet would be able to feed fewer people than land use based on an omnivore diet. So, it means that completely and suddenly eliminating animal-based products may not be the most sustainable option in the long term for humanity. A vegan diet may not be the best choice for the functioning of the human population, their protein needs and world soil resources management.