By Matt Blitz
Updated August 22, 2016
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Credit: Courtesy of Greenling

According to a 2012 Gallup poll, 5% of Americans consider themselves vegetarians. That number may be small, but the number of actual vegetarians in this country may actually be smaller. According to a 2011 Psychology Today article, many who claim to be aren't completely vegetarian, but rather are people who follow a "vegetarian-inclined diet." A 2003 USDA study highlighted in the article confirms that "self-defined" vegetarians may still eat meat, but they eat less of it and are generally considered healthier than the general population.

Even if their numbers are comparatively small, vegetarianism is not a new phenomenon. In fact, anthropologists believe that many of our ancestors were vegetarians, eating nuts, fruit and ancient fungus. While it was previously thought that Neanderthals ate mostly meat, a 2012 science journal article explains that plant-material accounted for large portion of their diet. Sure, our human forebears ate meat on occasion, but it was often difficult and dangerous to catch. So, they relied on non-moving food (vegetation) as sustenance. That's not to say that humans had no need for meat. A 2012 study concluded, based on the studying of skulls, that human evolution could have only happened with a high-energy diet, one that could have not been maintained by plants alone. A 2016 report in Nature confirmed that humans needed meat to evolve. In other words, as one researcher put it, "I know this will sound awful to vegetarians, but meat made us human."

4000 years ago, humans began making the choice not to eat meat. Ancient Egyptians' diet, according to a recent finding, relied mostly on cultivated wheat and barley rather than meat and fish. This might be surprising considering the civilization's proximity to the Nile, but researchers theorize this was for religious reasons. Cows, rams, pigs and geese were all considered sacred in ancient Egypt. Not only did Egyptians at the time rarely eat meat (only during festivals and special occasions), they also frowned upon the wearing of animal flesh.

A millennium later, spirituality also played a role in a group of Greeks' choice not to eat meat. The mathematician and early animal rights activist Pythagoras (yes, of triangle fame) likely adhered to a strict vegetarian diet (including the eating of honeycomb) and inspired a committed following. Believing that all living things had a soul and were capable of ethical choices, Pythagoras considered it wrong to treat any animal differently than one would treat a human. There are legendary stories of him stopping a man from beating his dog because the dog was an "old friend," convincing a wild boar to be less aggressive and releasing a fisherman's catch back into the sea. Although it was common at the time to sacrifice animals to the gods, the story goes that when Pythagoras discovered the properties of the right angle triangle he instead sacrificed dough in the shape of an ox. Pythagoras also believed that abstaining from eating animals was conducive to peace. He thought if one was righteous to animals, then they must think it was "more unjust and unlawful to kill a man or to engage in war."

Greek and Roman vegetarians who came after Pythagoras started calling themselves "Pythagoreans." This included Aristotle, the Roman philosopher Seneca and the poet Ovid. As the decades and centuries went on, other famous people adhered to be the "Pythagorean diet," like Ben Franklin, philosopher Leo Tolstoy and Little Women writer Louisa May Alcott. According to the Online Etymology Dictionary, the word "vegetarian" - a combination of vegetable and agrarian - came about with the formation of Vegetarian Society in England on September 29, 1847. Three years later, the "American Vegetarian Society" formed in New York City. The early meetings were attended by many notable progressive Americans of the time, including journalist Lucy Stone, abolitionist Horace Greeley and suffragist Susan B. Anthony.

For the next century or so, vegetarianism operated on the fringes of society and, rather oddly, in step with the eugenics movement. Nobel Prize winner playwright and George Bernard Shaw a eugenics enthusiast was a well-known vegetarian. So was John Kellogg, the inventor of corn flakes and a healthy living advocate. He was also really into eugenics. Eugenic-promoting doctors of the day also said vegetarianism was a way to "unpolluted" the human race. In 1947, the American Vegetarian Party launched, nominating candidates for president until 1964. Their first candidate was a Chicago naturopathic doctor named John Maxwell. Unfortunately, he was born in England and therefore not eligible to be President of the United States.

In 1971, grad student Frances Moore Lappe wrote the best-selling book Diet for a Small Planet and is often credited for bringing vegetarianism into the mainstream (and thankfully away from eugenics). Promoting the diet as not just ethical and moral, Lappe also makes a practical argument around how it limits human impact on the environment. Coming on the heels of Rachel Carson's eye-opening Silent Spring, the book and the diet it promoted spoke to a much broader range of people than it had previously.

40 years later, it is not only vegetarianism that continues to have a loyal following but its stricter variants as well. In England for example, the number of vegans has risen 360 percent in a decade. It seems what is old is new again and more people are reverting back to the diet of our ancestors from millions of years ago.