On the basis of both health and ethics, the case for eating a mostly plant-based diet is strong.
The health case is all but irrefutable. It is impractical to cite all of the relevant evidence here. If one goes to the National Library of Medicine website and types "vegetarianism AND health" into the search box, more than 730 peer-reviewed articles pop up. I cite some portion of that evidence in the chapter on vegetarianism (chapter 43 for those who have the book) in my textbook, "Nutrition in Clinical Practice, 2nd Edition" (2008). In this pop culture forum, however, we may reasonably limit ourselves to the view from altitude and noting that relevant citations include intervention studies, nutrient studies, epidemiologic studies, trans-cultural comparison studies and ethnographic studies of cultural transitions.
But before the more zealous carnivores start sharpening spears or pitchforks, and despite my prevailing support for the vegans, I must add that neither on the basis of health, nor ethics, do I find a decisive case for only eating only plants.
The surest sign you're on the middle path is that people on both sides of you are telling you why you're wrong (often in terms unsuitable for prime time). In this instance, I anticipate the wrath of staunch carnivores and devout herbivores alike. Oh well.
I addressed in my prior post the evidence against veganism as the ONLY health-promoting diet. Rather than revisit that argument here, I will simply reassert the takeaway message. Both entirely plant-based and mostly plant-based diets have been linked to powerful health benefits as compared to the typical American diet, the many glow-in-the-dark constituents of which might be hard to assign confidently to either the plant or animal kingdom. There have been no decisive, long-term comparison trials of optimal omnivorousness versus optimal vegetarianism, and perhaps never will be. The evidence available shows that eating only plants can reduce heart disease risk by 70 percent or more, and so can adopting a Mediterranean diet that includes animal foods. Impassioned arguments to the contrary notwithstanding, on the basis of evidence -- it's a draw.
Eating only plants -- whether vegetarianism or veganism -- is generally a good idea, and when practiced well, an excellent idea -- for health, for the kinder, gentler treatment of our fellow species and for the preservation of our planet. That is a trifecta if ever there was one, so I lend my very strong support to well-practiced vegetarianism.
But the fact that there are variations on the theme of eating well -- both health-related and ethics-related variations -- allows for more of us to opt in, and fewer to renounce the whole enterprise.
The ethical case against eating animals generally originates with our place in the animal kingdom. We are, of course, animals. We are not vegetables, or minerals and, in a time-honored, if admittedly simplistic cataloging of the universe, there's nowhere else to hide. Ethical arguments ensue from one of two fundamental assertions: We are like other animals, or we are different from them.
Let's start with being like other animals. I embrace this as the stronger claim not only on the basis of richly detailed renderings of evolutionary biology and molecular genetics, but on the basis of a far more intimate knowledge. Two animals -- dogs, to be specific -- are among the very best friends I have.
Living with these two animals and sharing friendship with them allows me to see just how much alike we are. I love them, they love me. I know joy, anxiety, fear, anticipation, delight and irritation -- and so, very clearly, do they. I can be impatient, thankful, annoying, loyal, affectionate and contrite -- and so can they. I can solve problems, and so can they -- albeit less complex ones (of course, they also create less complex problems!). I like some people and dislike others -- so do they. I remember what matters to me -- and they remember what matters to them.
By any measure that counts -- intelligence, resourcefulness, capacity to love, self-awareness, loyalty -- I find that Bramble, Zouzou and I differ only by degree, not kind. We are much alike. And of course, this isn't only about my dogs, or dogs in general. All animals are related at one remove or another, and all life is a continuum.
The ethical case builds from there. It is inarguably wrong (at least in modern society) for humans to practice cannibalism and eat other humans. Other animals are members of the extended animal family. It is therefore wrong for, presumably, lesser versions of all the same reasons to eat other animals. Rationalizing the eating of some animals, but not others, is rank "speciesism."
But this argument quickly falls apart under scrutiny. If it is wrong for humans to eat animals because we are so alike, then what applies to us must apply to them. In other words, the logical extension of this thinking must be: It is wrong for any animal to kill and eat any other animal.
This is just silly. It is silly for many reasons, among them the fact that some animals are obligate carnivores and could not survive by any means other than killing and eating other animals (sometimes in drawn-out, painful and rather brutal ways). It is also the very height of presumption for creatures born into a natural world to declare that natural world in its normal workings "unethical." It would be as if carbon-based life forms decided it was unethical to use up carbon in making life forms. We could assert it, but it would be nonsense.
We should extend this reasoning a bit and note that it would be silly for modern humans to declare animal eating by pre-modern humans unethical. While there seem to be some differences of opinion among anthropologists about the extent to which our forebears were hunters vs. gatherers, there appears to be universal consensus that they were both. Hunting extends even beyond the timeline of our species, to populate earlier entries into the genus Homo. Was it unethical for Homo erectus to hunt and eat what it killed?
There would be no modern ethical vegans had there been no Stone Age hunters feeding their ancestors, because those ancestors would have starved before ever making babies. (As I have noted on prior occasion, people who don't survive to make babies make very poor ancestors.) In contrast, there could certainly be modern meat-eaters whose meat-eating ancestors were fed by hunters, with no help required from ethicists. I am not sure it is reasonably in the purview of ethicists to declare as unethical something on which their existence depends.
It cannot be unethical for animals to kill and eat other animals. And it cannot be unethical for humans to have done so throughout their history. So can we make the ethical case based on how different we are from both other species, and our former selves?
In one sense, no. Biologically, we are the same as our former selves -- at least the same as we have been for tens of thousands of years, if not far longer. And while we might argue we are fundamentally different from other animals, that might as readily destroy as make the argument against eating them. If animals are so different from us, why extend to them the same ethical considerations we apply to ourselves?
But in another sense, there is a case to be made based on how different we now are from other species, and our former selves. That sense is our impact on the planet.
In our voracious, resource-devouring multitudes, we are exerting a force no other species has ever approached, and which our Stone Age ancestors could not have imagined. In that sense, we are genuinely different.
The ethical issue has little to do with whether or not we eat animals. Instead, it has everything to do with how we turn them into food. Knowing, willful neglect or abuse of any creature by any other is unethical. It may be that only humans can be "knowing" about such things, which would give us a basis to limit ethical considerations to ourselves. It allows us to exonerate the occasional brutality of lions, or Komodo dragons. But if fully conscious, premeditated abuse of one creature by another is not unethical, it's hard to see how anything is.
A growing mass of humanity with a penchant for meat inexorably drives the supply side toward methods of mass production, involving cost-savings and corner-cutting. Animals are fed food unrelated to their native diets. They are crowded together. They are dosed with antibiotics and hormones. There are expedient means of turning creatures into chops and patties that, according to a litany of first-hand accounts, play out very cruelly.
In other words, the mass production of meat can obliterate the life of the animal whose meat it is. A steer is turned into something other than a creature -- it's just a whole bunch of hamburgers on the hoof. By almost any defensible definition of ethics, the practices that ensue from depending on animals for food to the extent that we do -- are over the line.
Let's wrap up. Staunch proponents of veganism tend to over-interpret the evidence for plant-based eating, strong as it is. While it is clear that eating mostly plants is far better than hardly eating plants prevails in the U.S., it does not follow that eating only plants is the only way to eat well. Advocates of meat-eating who base their arguments on our ancestral consumption of meat overlook how radically different modern, domestic, mass-produced animal flesh is from the variety our ancestors ate.
As for the ethics, there are too many of us Homo sapiens on the planet already, and every reason to believe there will be many more of us before we control our population growth. Most of us who can, eat too many animals and animal products. The combination of our multitudes and our appetites results in the mass production of animal foods, which in turn results in -- or at least invites -- terrible abuses.
Perpetrating abuse while knowing it is abuse is unethical, if anything is. Eating animals may not be intrinsically unethical, but the means in this case may un-justify the ends. If we must maltreat animals to produce the volumes of animal food we demand, then we should stop demanding such volumes of animal food.
There is, however, some latitude left in the solution.
It would be fine if all of us were to eat only plants. But if most of us were to eat mostly plants, we could raise many fewer animals for food, and could treat those we do... ethically. There is more than one way to eat well and do good. The prevailing norm at present, however, isn't one of them.