There's a theory, still argued over by anthropologists, that our brain got as large as it did because our ancestors started eating enough protein to fund it. The brain is expensive to run, using close to a fifth of the body's energy at rest, and something had to pay for that. The leading idea is that denser, protein-rich food, meat, marrow, fish, eventually cooked food, let the gut shrink and freed up energy for the brain, a straightforward trade between two hungry organs. It's not fully settled, some newer research credits cooperative childcare and social living just as much as diet, but either way protein wasn't incidental to becoming human. It was part of the machinery.
Its importance doesn't fade with time, it changes shape. As you get older, the body gets less efficient at using protein to build and hold onto muscle, a process with the unglamorous name sarcopenia, and appetite tends to shrink at exactly the point the need for protein goes up. There's a false story a lot of older people are still quietly living by, the one that says careful eating means eating less, because getting fat is still the thing to fear most. I've heard a version of this from a woman in her nineties, who turns down a second yoghurt because she's watching her weight, while she can no longer manage the stairs without help. That fear was useful once, decades ago. It isn't anymore. Past a certain age, the real risk usually isn't a bit of extra weight, it's not having the strength left to get up out of a chair unassisted. Eating more protein, not less, is often exactly what's needed to fight that.
Pulses were a typical and readily available source of protein long before money or industrial food existed. Which pulse depended entirely on where you were standing. Lentils have fed South Asia and the Middle East for thousands of years, ground into dal, simmered until they collapse into something warm and whole. Chickpeas and fava beans did the same work around the Mediterranean, pounded into hummus, or simmered slowly with garlic, cumin, and oil into ful medames, the fava bean stew that's been Egypt's everyday breakfast for centuries. Across the Americas, beans and corn grew alongside each other and were eaten the same way, a pairing so old it predates written history in that part of the world. In West Africa and later the American South, black-eyed peas carried the same job. And in the British Isles, it was dried peas and broad beans, boiled for hours into a thick pease pottage kept going in the pot for days at a time, replenished rather than remade. It mattered enough that for two hundred years, from the 1400s through the mid-1600s, "pottage" simply meant peas. There's still a nursery rhyme that remembers it exactly, pease porridge hot, pease porridge cold, pease porridge in the pot, nine days old, a rhyme about leftovers that were never really leftovers, just the same pot, carrying on.
Meat earns its reputation for a plain reason, it carries all the amino acids the body needs in one place, no combining required, which is why it became the benchmark everything else gets measured against. A piece of chicken, a bit of beef, a fillet of fish, all get you there in a single mouthful, efficiently, without needing to think about it. That's not a small advantage, and it's exactly why so much of the world built meals around it whenever it could be afforded. None of what follows here is arguing against that. It's just that meat was never the only route to the same destination, and knowing the others gives you more nights where dinner doesn't depend on whether there's any in the fridge.
That certainty about meat is fairly recent, and it came from somewhere specific. Across much of Europe, meat was scarce and tightly rationed through the war years, and for many countries the shortages ran on well after the fighting stopped. Spain, still recovering through the 1950s, was eating less meat than Greece or Turkey at the time. Then the 1960s and 70s brought real economic growth across the continent, and meat consumption climbed sharply almost everywhere it reached, in Spain, in Italy, in Britain, becoming something closer to a symbol of having arrived than an ordinary ingredient. For the generation that grew up either through the scarcity or in its long shadow, meat on the table every day wasn't a lifestyle choice, it was proof the hunger years were over and weren't coming back. That's a reasonable thing to want to hold onto, having lived through actual scarcity. It also meant the habit got passed down as a rule rather than a memory, so plenty of people inherited "meat at every meal" without ever being told why it mattered so much to the generation that taught it to them. Plenty of other food cultures, in the Mediterranean, across Asia, in much of the world that never went through that particular postwar rush, never made the same rule at all, and ate meat occasionally, as one good thing among many, without ever treating its absence as a problem to solve.
Tofu deserves its own word here, and its own history. It's been made in China for around two thousand years, and travelled to Japan with Buddhist monks, whose vegetarian practice needed a reliable source of protein that didn't involve meat, the same principle of non-violence that shaped Buddhist temple cooking generally. But tofu wasn't only a religious solution. Pork has been the everyday meat in China since roughly 4000 BC, and for most of history it stayed a luxury few could actually afford, so it was ordinary people, not the wealthy, who leaned hardest on soy and tofu, simply because meat was out of reach. The soybean itself did more quiet work than tofu alone, fermented into pastes and sauces, ground into milk, dried into sheets, all ways of getting real protein out of a bean that's otherwise fairly plain on its own. That's the real reason tofu sits at the centre of so much Asian cooking, not fashion, necessity, built to feed people who couldn't or wouldn't eat animals, in numbers large enough to matter. It has almost no flavour of its own, which is precisely the point. It takes on whatever you put around it. Pressed hard to squeeze the water out, then fried until the outside goes properly golden, it holds a marinade the way meat does. Silken tofu goes the other way, soft enough to blend into a dressing or a dessert without anyone noticing it's there.
None of this is really about picking a side. Meat, pulses, tofu, eggs, dairy, whatever ends up on the plate, the decisive factor was always just what was available and suitable for the person eating it, and that's still true now. Someone with easy access to good meat and a taste for it has no reason to complicate things. Someone who can't get it, can't afford it, or simply doesn't want it has just as many ways to get there. There's no correct answer sitting above the others, only what actually works for you, in your kitchen, on an ordinary Tuesday. You decide what you do. But it's best to have protein.
You don't need a slab of meat to hit a decent amount of protein at every meal. A tin of chickpeas thrown into whatever you're already making, a handful of red kidney beans stirred through a salad, a spoon of white beans mashed into a soup at the end, all of it adds real protein for no extra effort at the stove.
