Meat remains a hotly debated food in modern diets, with more people adopting vegetarian or flexitarian lifestyles—eating meat only occasionally. Beyond taste preferences, are humans truly built to consume meat, or is a plant-based diet more natural?
According to the latest Food and Agriculture Organization of the United Nations report, global meat production is projected to rise 2.2% in 2021, reaching 346 million tonnes. Yet, driven by ethical concerns like animal welfare and environmental impacts—such as livestock's role in greenhouse gas emissions, deforestation, and water pollution—many are cutting back.
Meat provides high-quality protein, vitamin B12 (vital for brain, nerve, and blood health), and iron. Evolutionary experts suggest it fueled early human brain growth and cognition. Today, though, diverse protein sources abound. Does continuing to eat meat still make sense?
From 4 to 2 million years ago, australopithecines thrived on plants: roots, leaves, and fruits. Their diets later included insects, eggs, and small animals, making Homo habilis omnivorous. Homo erectus hunted larger prey, and Homo sapiens became hunter-gatherers, eventually domesticating animals and cultivating crops. Humans have eaten meat for hundreds of thousands of years.
Anatomically, modern humans lack the hallmarks of strict carnivores—like long canines and sharp molars seen in lions, tigers, or wolves. We're also unlike herbivores, with their flat teeth for grinding plants and elongated digestive tracts for fibrous foods.
Most species' dentition and guts align perfectly with their diets; ours suit a mixed animal-plant intake. Our closest relatives, great apes, mainly eat nuts, fruits, leaves, and insects, with rare meat. Evolutionarily, a mostly vegetarian diet with occasional meat fits us best.
Researchers posit higher meat intake aided human brain expansion (for language and communication) and bipedalism. The energy-hungry brain may have shrunk our digestive tract relative to body size compared to other primates.
Today's world offers vast food variety unlike our ancestors'. Meat isn't crucial for essential nutrients anymore—and excess may harm us.
Cooking methods matter: Barbecuing or high-heat smoking releases fats that form polycyclic aromatic hydrocarbons (PAHs)—known carcinogens—on meat surfaces. High temperatures also produce heterocyclic amines (HCAs), linked to cancer.
Studies associate high red meat consumption with chronic diseases, including colorectal, prostate, kidney, and breast cancers. In 2015, the International Agency for Research on Cancer (IARC) deemed red meat (beef, veal, pork, lamb, etc.) "probably carcinogenic" and processed meats "carcinogenic." Plant-based diets, conversely, lower risks of major illnesses.
Since 2009, alpha-gal allergies—triggered by a carbohydrate in non-primate mammal meat—have emerged in the US, Australia, and Europe.
Excess meat threatens health and the planet: Intensive farming accounts for 14.5%–16.5% of global emissions, surpassing all transport. Annually, over 64 billion land animals and 1 trillion marine ones are slaughtered for food, notes the Swiss group PEA on World Vegan Day.
Change is underway. School canteens now offer weekly vegetarian options. A 2021 Climate Action Network and Harris Interactive survey found half of French people reduced meat intake in the past three years, with 30% planning to continue.
Protein abounds in fish, eggs, legumes (lentils, beans, peas, soy), nuts (walnuts, almonds), cereals, crustaceans, mollusks, fatty fish (sardines, mackerel), and dairy. Vitamin B12 is covered too. Meat isn't necessary today—cutting back, especially red meat, benefits personal health and the environment.
