In general, people who eat meat stick to one base argument: It’s “natural” for humans to eat meat. Surely you’ve heard this before, whether it was from your parents, grandparents, or siblings or even your friends. It IS a convenient excuse to deny any responsibility for the horrific ways that animals are raised and slaughtered for food. However, how true IS this statement? Are humans really supposed to eat meat?


Let’s take into consideration the obvious fact that most humans are revolted by the sight of blood, intestines, and raw flesh and can’t tolerate hearing the screams of animals being ripped apart and killed. Real carnivores take pleasure in killing and eating raw flesh. Any HUMAN who killed an animal with his or her bare hands and then ate the raw corpse would be considered deranged. Carnivorous animals are excited by the scent of blood and the thrill of the chase. The bloody reality of eating animals is innately repulsive to us.


Vegan Sidekick 

Let’s talk about the human body. Humans have short, soft fingernails and tiny canine teeth. Try to imagine catching and ripping apart an animal with those! All true carnivores have sharp claws and large canine teeth that are capable of tearing flesh. Real carnivores’ jaws move only up and down, requiring them to tear chunks of flesh from their prey and swallow them whole. Humans and other herbivores can move their jaws up and down and from side to side, allowing them to grind up fruit and vegetables with their back teeth. Like other herbivores’ teeth, humans’ back molars are flat for grinding fibrous plant foods. Carnivores lack these flat molars.


Dr. Richard Leakey, a renowned anthropologist, summarizes, “You can’t tear flesh by hand, you can’t tear hide by hand. Our anterior teeth are not suited for tearing flesh or hide. We don’t have large canine teeth, and we wouldn’t have been able to deal with food sources that require those large canines.”

Now, think about the way carnivores swallow food. They usually gulp down chunks of food whole, relying on their extremely acidic stomach juices to break down flesh and kill the dangerous bacteria in meat that would otherwise sicken or kill them. Our stomach acids are much weaker in comparison because strong acids aren’t needed to digest pre-chewed fruits and vegetables.


Even our intestinal tracts and colons differ greatly from those of carnivores! Carnivores have short intestinal tracts and colons that allow meat to pass through their digestive system relatively quickly, before it can rot and cause illness. Humans’ intestinal tracts are much longer than those of carnivores of comparable size. Longer intestines allow the body more time to break down fiber and absorb the nutrients from plant-based foods, but they make it dangerous for humans to eat meat.

The bacteria in meat have extra time to multiply during the long trip through the digestive system. Meat actually begins to rot while it makes its way through human intestines, which increases the risk of colon cancer. Since we don’t have strong stomach acids like carnivores to kill all the bacteria in meat, dining on animal flesh can also give us food poisoning.

According to the U.S. Department of Agriculture, meat is a significant cause of foodborne illnesses in the U.S. because it’s often contaminated with dangerous bacteria such as E. coli, listeria, and campylobacter. Every year in the U.S. alone, food poisoning sickens more than 48 million people and kills more than 3,000.

Pigs crowded in factory farm

Jo-Anne McArthur / We Animals 



Dr. William C. Roberts, editor of the authoritative American Journal of Cardiology, sums it up this way: “[A]lthough we think we are one and we act as if we are one, human beings are not natural carnivores. When we kill animals to eat them, they end up killing us because their flesh, which contains cholesterol and saturated fat, was never intended for human beings, who are natural herbivores.” If we were meant to eat meat, why is it so damaging to our bodies?

Unlike humans, carnivorous animals in the wild virtually NEVER develop heart disease, cancer, diabetes, strokes, or obesity—ailments that are caused in humans largely by the consumption of the saturated fat and cholesterol found in meat. Studies have shown that even when fed 200 times the amount of animal fat and cholesterol that the average human consumes each day, true carnivores did not develop the hardening of the arteries that leads to heart disease and strokes in humans.


Human bodies weren’t designed to process animal flesh, so all the excess fat and cholesterol from a meat-based diet can make us sick. Heart disease, for example, is the NUMBER ONE KILLER in the U.S., according to the American Heart Association, and medical experts agree that this ailment is largely the result of the consumption of animal products. Meat-eaters have a 32 percent higher risk of developing heart disease than vegetarians do!

According to the Centers for Disease Control and Prevention, most Americans get MORE THAN enough protein, without paying special attention to their diets. A high-protein diet can sometimes restrict carbohydrate intake so much that they can result in nutritional deficiencies or insufficient fiber. It may also increase your risk of heart disease and may worsen kidney function in people with kidney disease because your body can have trouble eliminating all the waste products of protein metabolism.


According to nutrition expert T. Colin Campbell, the director of the Cornell-China-Oxford Project on Nutrition, Health, and Environment, “In the next ten years, one of the things you’re bound to hear is that animal protein … is one of the most toxic nutrients of all that can be considered.” With all these health risks, WHY did humans EVER turn to meat? The answer is quite simple.

During most of our evolutionary history, we were largely vegetarian: Plant foods, such as yams, made up the bulk of our ancestors’ diet. The more frequent addition of modest amounts of meat to the early human diet came with the discovery of fire, which allowed us to lower the risk of being sickened or killed by parasites in meat. This practice didn’t turn our ancestors into carnivores but rather allowed early humans to survive during periods in which plant foods were unavailable.


Vegan Sidekick 

Until recently, only the wealthiest people could afford to feed, raise, and slaughter animals for meat, while less wealthy and poor people ate mostly plant foods. Consequently, prior to the 20th century, only the rich were plagued routinely with diseases such as heart disease and obesity.

Since 1950, the per capita consumption of meat has almost doubled. Now that animal flesh has become relatively cheap and is easily available (thanks to the cruel, cost-cutting practices of factory farming), deadly ailments such as heart disease, strokes, cancer, and obesity have spread to people across the socio-economic spectrum. As the Western lifestyle spills over into less developed areas in Asia and Africa, people there, too, have begun to suffer and die from diseases associated with meat-based diets.


Basically, not only is meat not meant to be eaten by humans, it could be actively KILLING us! Now, you have all the facts you need to respond to anyone who tries to use biological need as an excuse to consume dead animals. Going vegan is the most compassionate thing you can do for animals AND your body!

With all the cruelty-free options available at grocery stores and restaurants nowadays, going vegan is easier than ever. Order our free Guide To Going Vegan to get started! 

Order peta2's FREE Guide to Going Vegan! *Heads up: Orders can take up to six weeks to arrive. If you need materials sooner than this, please contact us so we can help you out. If you have already requested that another pack be sent to you, please wait until you have received and used up that pack before ordering another 🙂

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