Should We Eat Meat?
The meat question, unsettled
Description
In 2013, the Canadian energy and environment scholar Vaclav Smil published a book with a title that reads like a dinner-table provocation: Should We Eat Meat? Smil is not the kind of writer who provokes for sport. He spends most of his career counting things — barrels of oil, tons of steel, calories of food — and he approached meat the way he approaches everything, by refusing to answer the question before he had measured it. The book runs to more than three hundred pages and barely raises its voice. It is a work of arithmetic aimed at one of the loudest arguments we have.
That argument usually arrives pre-packaged. On one side, meat is a moral catastrophe: cruel to animals, ruinous to the planet, a luxury the world can no longer afford. On the other, it is the food that built us, the reward at the center of the plate, a right nobody should be lectured out of. Smil finds both positions impatient. Meat, in his telling, is neither villain nor birthright. It is a substance with a deep evolutionary history, an enormous industrial footprint, and a set of numbers that almost nobody bothers to look up before taking a side.
What makes the book unusual is that it treats an ethical question as a quantitative one first. Before we decide whether we should eat meat, Smil wants to know how much we already eat, what it costs to produce, what our bodies actually need, and where the waste hides. Only then does the question become answerable — and the answer is not the clean verdict either camp wants.
The question we’re asking : When one of the world's most rigorous counters of things turns his arithmetic on the meat on our plates, what does he find that the shouting has missed?What we’ll see : How a systems thinker measures meat from every angle — evolution, industry, environment, ethics — and lands somewhere neither side expects.
Table of contents
01Chapter 1 — A species that became carnivorous by choice
Smil begins where the argument almost never does: several million years back, with our ancestors. Meat, he argues, is not a modern indulgence layered onto a naturally herbivorous animal. It is written into what we became. Somewhere in the transition from earlier hominins to the genus Homo, our forebears began eating more animal tissue — first scavenged, later hunted — and the consequences were physical. Animal foods are dense in energy and complete in protein, and Smil links their steady intake to one of the more expensive organs in nature: the large human brain, which burns a disproportionate share of the body's energy.
He is careful not to overstate it. He does not claim meat alone made us human, and he resists the tidy story that we are simply built to be carnivores. Our biology is that of a flexible omnivore, capable of thriving on a wide range of diets. What the record shows, in his reading, is that access to animal protein loosened a constraint. A gut shrank, a brain grew, cooking arrived, and diets across the deep past varied enormously by climate and geography — some groups leaning heavily on meat, others barely touching it.
02Chapter 2 — The machine that turns grain into flesh
Modern meat, Smil shows, is less an agricultural product than an industrial one. The animal on the plate is the output of a conversion system: crops grown on a vast scale, fed to confined animals, transformed into edible tissue at a fixed and unforgiving rate. That rate is the hidden fact around which everything else turns. It takes several units of feed to produce one unit of meat, and the ratio varies sharply by animal — chickens are efficient converters, pigs less so, cattle least of all. Beef, in Smil's accounting, is the most expensive protein we produce by almost every physical measure.
The scale is what staggers. Global meat output multiplied many times over the twentieth century, and a system that once relied on animals grazing marginal land now relies on animals eating grain that could, in principle, feed people directly. A large share of the world's harvested cereals and soybeans is routed through livestock. Smil does not treat this as automatically wasteful — ruminants can digest grasses and crop residues we cannot eat, turning worthless cellulose into protein — but he is clear that grain-fed industrial meat is a different proposition, a deliberate choice to trade calories for a preferred food.
03Chapter 3 — The true bill: land, water, nitrogen, methane
The environmental case against meat, Smil agrees, is real — but he wants it stated correctly. Livestock occupy an enormous share of the world's agricultural land, both as pasture and as the cropland devoted to feed. They are a leading driver of deforestation where grazing and soybean expansion push into forest. And they emit greenhouse gases through several channels at once: the methane belched by ruminants, the nitrous oxide released from manure and fertilized feed crops, and the carbon dioxide from the fuel and land-clearing behind the whole operation.
Nitrogen is the thread Smil follows most closely, because it is his home territory. Modern meat leans on synthetic fertilizer to grow feed, and much of that nitrogen never reaches an animal or a human at all — it leaches into water, off-gases into the air, and unbalances ecosystems downstream. Meat, in this view, is not just a climate problem but a nutrient-cycle problem, a place where the flows that industrial agriculture unleashed run especially inefficient. The animal is the point where a lot of energy and nitrogen quietly disappear.
04Chapter 4 — Neither the vegan nor the omnivore is right
Step back from the individual chapters and the shape of Smil's method becomes the real argument of the book. He is temperamentally allergic to moral absolutes, and meat is the perfect subject to demonstrate why. The abolitionist position — that eating animals is simply wrong and should end — collides with biology, culture, and the fact that some grazing land can feed people no other way. The maximalist position — that meat is a natural right to be enjoyed without limit — collides with the numbers on land, nitrogen, and climate. Smil's contribution is to refuse both and to quantify the space between them.
His conclusion is deliberately unglamorous: rational meat eating. Not zero, not the extravagant levels of the wealthy West, but a moderate intake that meets human nutritional needs without wrecking the systems that sustain it. He points out that the affluent world eats far more meat than health requires, and that trimming excess consumption would deliver most of the environmental benefit that outright abstinence would, at a fraction of the disruption. The target is the surplus, not the substance.
05Conclusion
Smil ends more or less where his title began — with a question he declines to slam shut. Should we eat meat? His honest reply is that the framing is wrong. The useful question is how much, of which kind, produced how, and the answer that falls out of his arithmetic is moderation: less than the rich world eats, more than the abolitionists would allow, and produced with far more attention to where the waste and nitrogen go. It is the conclusion of a man who counted before he judged.