The Inefficiency of Meat
3 Jan 2022
Early humans hunted animals that lived around them. Later humans found ways to farm certain animals. This saved the effort of the hunt as well as ensuring that there would be animals in the first place, but it also meant that the animals needed to be fed and cared for. Feeding farm animals requires more food than you could possibly get out, thanks to the first law of thermodynamics. But that wasn't a big problem because the food the animals were fed wasn't digestible to humans, e.g. grass, or wasted, e.g. scraps.
I used to believe this was still the case. Surely, industrial farming was using resources that otherwise couldn't be used. Statistics like "86% of all farmed animal feed is from human-inedible sources" seem to support this. When looking deeper into this however, my believe turned out to be false. And what better way to condense what I found than into an infographic that shows this?
Calories
It turns out that farmed animals eat a lot of human-edible food. Farmed animals consume 63% of all calories globally, yet provide only 19% of all the calories eaten by humans. Farmed animals als eat three times more of specifically human-edible calories than they provide. This holds up when measured in weight too, where every 1kg of animal product requires 3kg (dry weight) of human edible plants. On top of that, even more non-human edible feed is required (43% of all farmed plants). Although some of this would otherwise be wasted (e.g. stover, or harvest leftovers), a lot of it is specifically grown for animals to eat. This requires energy, space and labour, as well as an opportunity cost of growing more human food directly - about a third of pasture land is suitable to grow human-edible crops, roughly 700 million hectares. Note that these figures include fish. While wild fish eat no crops grown by humans and are very efficient is that sense, farmed fish on the other hand are often fed corn, soy, and vegetable oils.
On average, animal farming over the world is inefficient on calories from foods humans can eat. And when we include other feed, more calories are lost by feeding them to farm animals than are eaten by all humans. Plants grown directly for human consumption take up only 28% of all grown calories, but supply 81% of all calories eaten by humans. These are clearly more efficient, by a large margin.
Finally, 9% of all farmed plants are used for other uses, such as biofuel.
Protein
But that's all about calories. Animal products are of higher quality, they provide more protein, right?
Alas, this does not fill the gap. Remember that when looking at weight, we used dry weight for plants? When measuring the dry weight of edible plants their nutrient values are more or less equal to that of meat. With the big difference being that plants have more carbohydrates and meat has more fats. Calories and protein roughly balance each other out.
Looking at protein, 38% of al protein is supplied to humans via animal products. This is about twice the ratio of calories. However, this is offset by the farmed animal feed. This requires 42% of protein from all plants grown compared to 20% of all calories. In otehr words, farmed animals eat protein rich food, in fact, they eat more protein from human-edible sources than humans do.
Conclusion
By and large, animals are a very inefficient way to produce food. This is even before we look into animal welfare (more efficient methods tend to be crueler) and carbon emissions (animals eating grass rather than human-edible feed tend to be worse on emissions). If enough people eat less animal products or stop eating them altogether, much more food would be available for a growing poulation. This food is as rich in protein as the food currentyl available.
Unlike many other global issues, individuals can make a difference. Defining what people eat is unlikely to be set by governments, and companies will make the products people want. Rather than goverment or big company action, this is a change each of us individually can easily make. Three times a day, you can choose plants over meat, dairy and eggs and help stop this ineficiency.
Sources
Other related articles show similar figures, but have not directly been used for the infographic. E.g.: