Could we nourish an additional 3.5 billion people if we just ate the stuff we feed to animals?
In a popular YouTube video titled "Why Meat is the Best Worst Thing in the World 🍔" by the channel Kurzgesagt, they claim:
According to projections, we could nourish an additional 3.5 billion people if we just ate the stuff we feed to animals.
The source for information is a research paper titled: Redefining agricultural yields: from tonnes to people nourished per hectare, from which there is this example:
China feeds more people than India per cropland hectare with 8.4 people fed with delivered calories, albeit with a lower calorie delivery fraction of 62%. If all produced calories were food, that number would rise substantially to 13.5 people ha-1.
What I can't get my head around is the graph they have:
Maize and its fatty germs, have the biggest losses, but they are more suitable for digestion by ruminants. For us, we get little to no fat from maize, and compared to soybeans (which need more specific climates unlike maize), half the calories, and one-tenth the protein, for the same weight.
Are the projections correct (when we consider the different digestive systems)? Would using the same exact crops meant for animals (mostly maize) to feed humans really nourish an additional 3.5 billion people?
For example, we can produce corn oil for cooking: an industrial process that introduces inefficiencies, and after the oil is used for cooking, most of it is discarded. Since we can't break down maize directly like ruminants, wouldn't this skew the most directly consumable calories (by humans) per hectare?