Homo sapiens and all our direct ancestors evolved whilst partaking in heavily meat-inclusive diets. Even our closest living relatives, chimpanzees, regularly consume meat as one of the main constituents of their daily diet.
I shan't argue with those of the opinion that the consumption of meat is unethical. Ethics is subjective and arbitrary, and therefore cannot be proved logically and factually invalid. 'De gustibus non est disputandum', as the Romans would say (or if you prefer French to Latin, 'à chacun son goût').
But one should take care not to conflate or confuse their particular ethical sensibilities with scientific fact. Nor should one try to construe or contort real science in such a way as to make it meretriciously compatible with or corroborative to one's ethical proclivities.
Believe whatever you want. But don't distort reality and science to justify those beliefs, lest you become an ideologue.
As for the notion that meat is unhealthy (which is not proven) or at least not as healthy as non-meat foodstuff, it's not only unproven but arguably erroneous. Plants are doused with all kinds of toxic chemicals (pesticides, insecticide, herbicides (TCDD and other dioxins, for example), fungicides, etc.), which can act as endocrine disruptors, teratogens, mutagens, carcinogens, neurotoxins, and so forth.
Moreover, most plants have undergone hundreds of genetic modifications via genetic engineering (the result is typically termed 'genetically modified crops' or GMCs for short; they're sometimes also termed biotech crops).
Even for so-called "organic farmers", the seeds they purchase have almost always been genetically engineered; the "organic" plants themselves will also usually be inadvertently contaminated with synthetic herbicides and other chemicals due to herbicide volatilization and pervasive soil and water contamination.
So, meat is obviously less deleterious than plants insofar as the potentials for toxicity and pernicious medical effects are to be concerned. Meat is only contaminated indirectly as a result of animals eating contaminated crops.
Nothing has resulted in quite as much rampant pollution and excessive man-made environmental degradation as has agribusiness.
So, to reiterate: believe what you want to believe. But this dernier cri phytophilia cannot be justified by appealing to:
A.) evolutionary biology, anthropology,
and other evidence-based sciences, especially life sciences: since it's an incontrovertible scientific truism that humans evolved as meat eaters in much the same way as our ancestors did over the course of millions of years;
B.) health effects, nutritional value, and medical benefits: since these are all debatable;
C.) human nature: as we all know from history that human nature includes the eating of meat and whether one likes it or not or thinks it's unethical it remains an arrant fact. Most of what we know as human nature is arguably unethical to modern people as shown through the study of cultural universals and anthropology and thymology (rape, incest, infanticide, murder, pedophilia, torture, war, misogyny, pederastry, polygamy, adultery, thievery, racism, slavery, and so on), but something can be unethical and a fact of life at the same time;
D.) concern for animal welfare: since animals have never endured as much suffering as they have since the dawn of the Agricultural Revolution as a direct result of agriculture itself;
E.) economics: since meat is both cheaper to procure (a kg of beef is about as expensive as a kg of "organic" produce, yet cows are lower maintenance than a hectare of crops) and much easier for impoverished people to live off (a single adult cow could feed a family of five for a month or longer, whereas a month's worth of crops requires several hectares of land, fences and other protection from wildlife and pests, the right weather conditions or season, harvesting supplies, preparation, and so forth. Many more resources are necessitated than those needed to raise a calf into adulthood. Not to mention the inordinate water consumption of plants, which is considerable in developing countries where potable water is a scarce and valuable commodity).
So, in summary, there seems an exceptional dearth of both philosophical and scientific justification for the notion that meat is unethical and should be uneaten or at most consumed in strict moderation and with caution. Indeed, in the case of modern, Western vegetarianism and veganism, it seems the popular appeal preceded the rationale.
The consequence appears to be a clumsily coordinated and utterly unavailing endeavor to validate a foregone conclusion. The opinion should be informed by evidence, rather than having the evidence inspired by opinion. Vegetarians are in vogue, and herbivores are hip. But they're still demonstrably full of shit if they try to justify their choices by any means outside mere personal preference or ethical vagaries.
If anybody has an issue with the logic I've used and the facts I've employed in support of this comment, I'd enjoy hearing them. But, please, spare me the deontological drivel, utilitarian malarkey, and consequentialist claptrap; I don't argue over ethics, nor do I consider ethical objections to be valid arguments.