Your statement of June 8 that “we were born to eat meat” is nonsense. You made a major mistake in comparing the intestine-length-to-body-length ratio of a man versus a cat. The usual way to measure these things is from mouth to anus. In stating that man’s 23-foot-long small intestine is only four times his body length, you have clearly thrown in leg length. If you measure a man’s body length from mouth to anus like you would a cat or horse, you’ll find man’s intestine-to-body ratio is much closer to that of a plant-eating horse than a meat-eating cat.

In using comparative anatomy to determine what man was “meant” to eat, we should look at the species most similar to man, namely the anthropoid apes–chimpanzees, gibbons, gorillas, and orangutans. Of all animals, man’s digestive organs and teeth most closely resemble these apes. In captivity, some of these animals will eat meat if forced to rather than starve to death. But in the wild, all eat a vegetarian diet.

Another strong clue that man is naturally a vegetarian is the fact that vegetarians in general are much healthier than omnivores. The American Dietetic Association has acknowledged that vegetarians are less at risk for a number of chronic diseases, including heart disease, some types of cancer, obesity, high blood pressure, and adult-onset diabetes.

Eating a healthy diet goes far beyond cutting back a bit on red meat. In a recent study of 6,500 Chinese, Dr. T. Collin Campbell of Cornell found that even though the Chinese overall eat only a fraction of the animal protein Americans do, those who ate the least animal protein nonetheless had lower risk of disease than the average Chinese. Dr. Campbell concludes, “We’re basically a vegetarian species and should be eating a wide variety of plant foods and minimizing our intake of animal foods.”

–Glen Kime, president, Vegetarian Society of Washington, D.C.

I feel like I’m arguing that the pope is Catholic. To clarify a point that eluded many who wrote me about this: The issue is not whether vegetarianism is healthier, better for the planet, etc, than the standard U.S. diet. I have never doubted that it is. It’s whether humans are naturally vegetarians. Here it seems to me the best evidence is our history as a species. We have been happily eating meat for at least two million years, and probably much longer. The common view among anthropologists, in fact, is that increased meat consumption was a key element in the development of human culture, since getting and distributing the stuff requires cooperation.

Not all anthropoid apes are exclusively vegetarian. The primatologist Jane Goodall established more than 20 years ago that wild chimpanzees kill other animals once in a while and eat the meat with relish. Other primates (although apparently not gorillas) do so as well. It’s true chimps and other apes eat a mostly veggie diet, but for that matter so do most humans. Hunter-gatherers today consume only about 35 percent meat to 65 percent vegetables (Lee and Devore, 1976). Anyway, we and the anthropoid apes diverged 6 to 14 million years ago–who cares what monkeys munch now?

Your argument that meat eaters are more prone to chronic disease is irrelevant. Chronic disease typically strikes the old, not those of prime child-rearing age. Till recently most folks never got chronic disease because they died of the acute kind first. Chronic disease has had minimal impact on our ability to reproduce ourselves, which of course is the basis of natural selection. In short, as we evolved, chronic disease did not “select out” for vegetarianism. I trust you see the significance of this.

Your quibble about the measurement of intestinal length is not compelling. Even if we adopt your method and assume a three-foot “body length” for humans, our gut-to-body ratio is 8, about midway between plant-eating pigs and horses (20 and 12, respectively) and meat-eating cats (3). This tends to support the idea that we are omnivores.

There is much to be said for vegetarianism. I am at a loss to know why vegetarians cannot be content simply to say it, without taking the argument over a cliff.

Art accompanying story in printed newspaper (not available in this archive): illustration/Slug Signorino.