Narrator: Imagine a village in post-war Bohemia. It’s the middle of winter, and the community has gathered for a zabíjačka, the traditional winter pig killing. This isn't a sterile, industrial process; it's a festive, social, and culinary event. The entire animal is used, from blood sausages to roasted cuts, shared among families to sustain them through the cold months. This single event encapsulates a relationship with meat that is communal, resourceful, and infrequent. Now, contrast that with a modern supermarket, its aisles filled with an endless variety of pre-packaged meats, or a fast-food chain that serves millions of identical burgers a day. How did we get from one to the other? And what are the consequences of this monumental shift? In his deeply researched book, Should We Eat Meat?: Evolution and Consequences of Modern Carnivory, author Vaclav Smil provides a balanced, multidisciplinary examination of this very question, urging us to look beyond polarized debates and understand the complex realities of our carnivorous world.

Narrator: The debate around meat often overlooks a fundamental truth: eating meat is not a modern indulgence but a core part of our evolutionary heritage. Smil argues that carnivory is as integral to what makes us human as large brains and bipedalism. The evidence for this runs deep, even extending to our closest primate relatives. For instance, long-term studies of chimpanzees reveal that they are not strict vegetarians. They engage in sophisticated, cooperative hunts, often targeting red colobus monkeys. After a successful hunt, the meat isn't just consumed; it's shared strategically to reinforce social bonds and, in some cases, even exchanged for sex.

This behavior offers a window into our own past. Early hominins likely began as scavengers before developing the tools and social structures for large-scale hunting. This dietary shift to higher-quality, energy-dense food like meat is linked to the "expensive-tissue hypothesis." This theory suggests that to fuel the high metabolic cost of a growing brain, our ancestors' bodies had to make a trade-off: shrinking the size of the gastrointestinal tract. A smaller gut is less efficient at digesting large amounts of fibrous plant matter but is perfectly suited for nutrient-rich meat. In essence, eating meat may have been a crucial prerequisite for the very brain expansion that defines human intelligence.

Narrator: From a nutritional standpoint, meat is a uniquely potent food. It is a source of high-quality protein, complete with all the essential amino acids necessary for growth and repair. It is also packed with vital micronutrients that are often difficult to obtain from plants alone. Heme iron, found exclusively in meat, is far more easily absorbed by the body than the non-heme iron in vegetables, making even modest meat consumption a powerful defense against anemia—a condition that, according to the World Health Organization, affects over 1.6 billion people globally. Similarly, meat is a rich source of zinc and vitamin B12, nutrients critical for immune function and neurological health.

However, the benefits of meat are shadowed by significant health concerns. The same qualities that make it energy-dense—namely, its fat content—are linked to major "civilizational diseases" like cardiovascular conditions when consumed in excess. Furthermore, the risks are not uniform across all types of meat. Epidemiological evidence, while complex, consistently points to a stronger association between health problems and the consumption of processed meats like sausages and cured products, rather than lean, unprocessed cuts. The modern industrial system also introduces risks of contamination and meat-borne pathogens, a far cry from the fresh, locally sourced meat of traditional societies.

Narrator: For most of human history, high meat consumption was a luxury reserved for the affluent. In 1800, the average person in France consumed less than 25 kilograms of meat per year. By 1975, that number had quadrupled to nearly 100 kilograms. This dramatic shift, known as the "dietary transition," has been replicated across the developed world and is now occurring at an astonishing speed in modernizing economies.

The story of China provides a stark example of this rapid change. Following the economic reforms initiated by Deng Xiaoping in 1978, the country underwent one of the fastest dietary transformations in history. In 1961, in the aftermath of the Great Famine, the annual meat supply was less than 4 kilograms per person. By the year 2000, it had skyrocketed to nearly 50 kilograms. This was driven by rising incomes and a massive increase in domestic pork production, which ended decades of rationing and shortages. While this transition has lifted millions out of malnutrition, it has also placed an unprecedented strain on global resources, as a universal human propensity for eating more meat is unlocked by economic prosperity.

Narrator: To meet this exploding global demand, meat production has transformed from traditional, integrated farming into a highly specialized, industrial process. The modern meat chain is a marvel of efficiency, focused on manipulating the life cycles of animals to maximize output in the shortest possible time.

The U.S. broiler chicken industry is the quintessential example of this transformation. In the 1920s, raising a chicken to a market weight of about 1.3 kilograms took nearly four months. Through decades of systematic innovation—including selective breeding, optimized feed formulations, and the discovery that vitamin D supplements could allow birds to be raised entirely indoors—the industry achieved staggering results. By 2010, a modern broiler reached a weight of 2.6 kilograms in just 42 days. This process has been so successful that it has been replicated for pigs and, to a lesser extent, cattle, turning farms into landless, factory-like operations known as Confined Animal Feeding Operations (CAFOs). This system delivers affordable meat on a mass scale but has also severed the traditional link between animals and the land, creating a host of new ethical and environmental challenges.

Narrator: While the efficiency of the modern meat industry is undeniable, it comes at a tremendous environmental cost. A landmark 2006 report from the Food and Agriculture Organization, "Livestock's Long Shadow," identified the livestock sector as one of the top contributors to the world's most serious environmental problems. However, Smil argues that the greatest impact is not from the animals themselves, but from what it takes to feed them.

Producing the massive quantities of corn and soybeans required for animal feed necessitates vast tracts of land, often leading to deforestation. It also depends heavily on synthetic nitrogen fertilizers, whose production is energy-intensive and whose runoff pollutes waterways. The entire system is a major consumer of fossil fuels, from running farm machinery to transporting feed and finished meat products around the globe. In essence, the environmental footprint of a piece of meat is overwhelmingly determined by the footprint of the crops grown to produce it. This makes meat, particularly grain-fed beef, one of the most resource-intensive foods we consume.

Narrator: Ultimately, Vaclav Smil's analysis in Should We Eat Meat? steers clear of simple condemnation or praise. The book's single most important takeaway is that the core issue is not the act of eating meat itself—an act deeply woven into our evolutionary, cultural, and nutritional history—but the unprecedented scale of our modern consumption. We have transformed a traditional, occasional, and nutrient-dense food into a daily, industrial commodity, and our planet is straining under the weight of that decision.

The book leaves us not with a demand for universal vegetarianism, but with an appeal for rationality. It challenges us to move beyond the black-and-white thinking that dominates the conversation and to consider a middle path: eating less meat, choosing meat from more sustainable production systems, and drastically reducing the immense waste that occurs from farm to fork. The most profound question it poses is not if we should eat meat, but how we can do so in a way that nourishes both ourselves and the planet we depend on.