How belief too often precludes discussion

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Some time ago I happened to write an approving comment on someone else’s Medium article in which the author pointed out a simple truth: a strict vegan diet carries significant metabolic risks unless the practitioner takes steps to augment what is, for the human species, a sub-standard diet.

There is an abundance of evidence from human dentition through the gastro-intestinal tract that we humans are obligate ominvores. Indeed, paleontologists strongly suspect that the comparatively large brain of the genus homo is a direct consequence of a shift to augmenting a largely plant-based diet with increased consumption of animal products.

Furthermore, there is overwhelming clinical evidence that unless the practitioner takes supplements to augment a strict vegan diet, a wide variety of neurological impairments occurs in consequence of lack of vitamin B12. Additionally, sub-optimal omega-3 levels are frequently observed in vegan blood samples as are relatively high cases of anemia, in cases where vegans do not adequately augment their diet with appropriate supplementation.

There is a wealth of medical evidence supporting all these basic statements of fact, and links to a few references are given at the end of this article. There are, of course, a great many more references of the same sort and the interested reader is invited to do their own research among reputable sources such as various NIH-funded research institutions, the Mayo Clinic, and reference to the UK medical journal of record The Lancet.

Despite what appears to be a non-contentious itemization of evidence strongly supported by many independent studies, it turns out that some vegans prefer assertion over evidence and thus react adversely to any information that challenges their beliefs.

The problem is, when we cleave to beliefs and choose to ignore evidence (or, slightly more sophisticatedly, ignore evidence that contradicts our beliefs while promoting evidence of doubtful merit that appears to support our beliefs) we do everyone a disservice. The US Republican Party and the UK Brexiteers demonstrate all to well the perils of make-believe. Even if the only people who suffer from mistaken beliefs are a sub-set of vegans themselves, many more people may be led astray by unsupported assertions about the virtues of veganism. Currently fashionable is the notion that becoming vegan can “save the planet” by reducing methane emissions from cows, and by reducing total demand for water and plant materials. Thus veganism is frequently promoted as a “moral choice” rather than a fad diet.

Personally I understand why some object to consuming animal products, especially given the horrific conditions pertaining within the US agricultural system. Sadly, plant-based agriculture is just as industrialized and very nearly as harmful to the environment, as toxic algae bloom and suffocate large bodies of water in consequence of massive over-use of fertilizers and pesticides create havoc among insect populations. It’s understandable that some adopt veganism in reaction to becoming ill because of the appallingly unhealthy standard American diet. This is, however, very different from claiming that one’s personal choice is evidence of “superior” morality and even further from any notion that everyone else ought to do likewise, especially those few who were eating more adequately in the first place.

All-or-nothing thinking is seen, of course, in traditional religions, the mythologies of which each lay claim to superior morality and an ultimate “truth.” And traditional religions invariably lead to regressive thinking, forced imposition of restrictive norms onto others, and far too often violence both rhetorical and actual. For anyone doubting this last proposition, a little exposure to history will serve to elucidate matters further and the reader is encouraged to consult books on the various wars of religion that repeatedly tore Europe apart during the middle ages, as well as consulting news articles on current Buddhist genocide against Rohingya muslims in Myanmar, to cite merely two examples among hundreds.

The appearance of a dietary choice morphing into yet another religion is, therefore, somewhat depressing.

What I found most sad about the various responses by devoted vegans was the anti-intellectual tone that predominated. Nowhere did any outraged vegan cite actual scientific data; instead, Trump-like phrases and insults were to the fore. Perhaps this is because the most devout vegans are like the most devote religionists: in desperate need of a simple creed to which they can cling in a confusing and complex world. And as we all know, when someone’s beliefs are challenged it’s far easier to respond with vitriol than to take a moment to consider the actual data.

Whatever the case, I continue to believe that we collectively learn and consequently make better decisions if we use reason rather than assertion, if we look for well-supported data rather than crude polemic, and if we recognize that the choice of some may not be the choice of others.

And if people do choose to be vegan and supplement appropriately, they harm neither themselves nor (through putting a burden on the health care system) impose costs on others. But that very supplementation itself shows clearly that a vegan diet is insufficient for the human species. This much cannot be in doubt, except for those most desperate to believe otherwise in the face of all currently available evidence.

As always, belief is easy. Reason much less so.


Anyone who enjoys my articles here on Medium may be interested in my books Why Democracy Failed and The Praying Ape, both available from Amazon.

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