Human Teeth Are Not Particularly Well Adapted For Meat Eating

My friend’s brother once told me we humans must eat meat because of the shape of our teeth, which he claimed are good for biting and chewing meat. I replied that we use our brains to make decisions about what to eat and teeth don’t make decisions. 

Is it true that human teeth evolved over millions of years to primarily eat meat? The answer is no, because we humans for most of our existence were never carnivores such as lions, tigers, and wolves. Somehow, perhaps because some of our human front teeth, the incisors, appear somewhat sharp relative to the middle and rear teeth which are flatter, there has been an assumption the front teeth are specifically for biting and ripping dead animal parts, which is not true. “In his essay, Dr. Mills notes that not only are human teeth better adapted to a herbivorous diet but so is the entire mouth. Like other herbivores, our teeth are close together and flat, perfect for use on soft materials such as fruits. Even our elongated canines can be found in other apes, who use them primarily for display or defense. This contrasts with the teeth of carnivores which are spaced more widely apart and are more blade-like — ideal for shredding and tearing. 

“When considering the mouth in its entirety, humans also display other similarities to herbivores. Such markers include fleshy lips and a smaller mouth opening, very different from the hinge-like jaws of a cat or other carnivore. Our jaws are also able to move more freely than a carnivore’s, as we are able to move them both up and down and side to side, giving us greater use of our incisors while allowing us to crush and grind our food.”

Some scientists have studied human remains from long ago and found evidence their diets were mostly plant-based. “There is another place where scientists can look for clues to what early humans ate: their teeth. When researchers analyzed the tartar preserved in the stained teeth of two Australopithecus sediba individuals from South Africa, they found microscopic bits of silica from plants these hominins ate nearly two million years ago, including bark, leaves, sedges and grasses.”

One Neanderthal stereotype is that this group of humans was brawny but not too brainy and that they must have eaten a lot of meat. Well, maybe not. “Amanda Henry of Leiden University in the Netherlands and her colleagues found traces of legumes, dates and wild barley in the tartar on their fossilized teeth. And researchers led by Karen Hardy of the University of Glasgow discovered roasted starch granules in Neandertal teeth, in­dicating that they ate cooked vegetables. Some Neandertals might have even forgone animal flesh entirely: in a study co-led by Laura Weyrich of Pennsylvania State University, analyses of DNA preserved in the tartar of Neandertals found in El Sidrón cave in Spain turned up traces of pine nuts, moss and mushrooms—and no meat whatsoever.”

Pre-homo sapiens sometimes are described by the general populace in terms of what they learned in schools, where the knowledge of archaeology and anthropology was scant. What many of us have in our heads about how our pre-modern human ancestors lived might be hazy, with discombobulated timelines, outdated and incomplete. Paleo stories result where we may not have any basis for what we believe about how ancestors from millions or hundreds of thousands of years ago conducted themselves.

A 2025 Archaeology Magazine article explains: “Early humans were not the single-minded meat hunters often imagined in popular ‘Paleo’ narratives. A new study published in the Journal of Archaeological Research argues that our ancestors were skilled at gathering, processing, and eating a wide range of plants long before the first farms appeared. Researchers from the Australian National University and the University of Toronto Mississauga reviewed archaeological evidence from sites across the world and concluded that humans evolved as ‘broad-spectrum’ eaters, relying on diverse food sources rather than primarily on animal protein.”

My friend’s brother who assumed human teeth are well-suited to meat-eating was incorrect about human teeth and about what humans and pre-humans consumed long ago. He also had never studied the scientific research. Nevertheless, he was still opinionated on the subject.

Another false belief is that chimps and gorillas eat meat so humans must as well, but chimps and gorillas don’t actually do that in any significant quantity. “So how do the diets of humans compare with the diets of chimpanzees and other great apes, given our common ancestry? More different than you might think. Plant materials comprise 87% to greater than 99% of the annual diet of great apes, according to research published in the Journal of Nutrition.”

If you ask a man or woman walking in public on a sidewalk, “A million years ago, did our ancestors eat a lot of meat?,” that person might say, “Yes.” As we have seen, the notion is actually false. If the same person was asked, “What about wild black and brown bears, do they also eat a lot meat?” The same person might say emphatically, “Of course wild bears eat a lot of meat. They are constantly eating it.”

Is that true, though? Nope. Many wild black and brown bears don’t consume vast quantities of meat, “Bears are opportunists and feed on a wide range of vegetation and animal matter. Although bears eat meat, their diet is primarily vegetarian, including early greening grasses, clover, and the buds of hardwood trees in the spring, fruits and berries in summer, and beechnuts, acorns, and hazelnuts in the fall. This diet is supplemented with insects, including ants and bees (their larvae, adults, and honey), and occasional mammals and birds.”

So, even animals that some people assume are carnivores, such as some wild bears, actually are omnivores. They consume large amounts of diverse non-meat foods with some meat — they don’t only eat meat.

Some people might assume domesticated dogs are carnivores only because of their long, sharp, canine teeth, and that dogs must eat meat frequently to be healthy and to survive. Sorry to Captain Correction the readers, but this assumption is false. “Dogs are omnivores, capable of digesting both plant and animal foods. Research suggests they can survive, and in some cases thrive, on plant-based diets if carefully balanced.

“A 2022 peer-reviewed study in PLOS ONE compared over 2,500 dogs fed conventional, raw, and vegan diets. The findings were striking: dogs fed vegan diets had fewer vet visits and were reported as healthier overall compared to those on traditional meat-based kibble (Knight et al., 2022).

“Another angle worth noting: vegan diets naturally restrict methionine, an amino acid that cancer cells rely on for growth. Studies in cancer biology suggest that limiting methionine intake may help slow cancer progression (Gao et al., Nature, 2019).”

The point of this article is not so much to attempt a deep drive into the scientific literature. It is to demonstrate that our human teeth shapes do not prove we must consume meat, nor do they require it. Even some non-human species don’t need to eat a lot of meat.

CleanTechnica is not a health food website, it is about sustainability. The connection to food is the fact that some of the worst foods for climate change are beef, dairy products, farmed shrimp, lamb/mutton, and vegetable oils.