Third in this occasional series on vegan pork pies (lies) is this: soy consumption equals longevity. This is still commonly found around the Internetz: a website about super-aging has a section on the Okinawans. ‘Eat more soy,’ it says, as a key to longevity. And it is via the Japanese island of Okinawa that this vegan myth, helped along by the pro-vegan food writer John Robbins, emanates. Centenarians run, or used to run, at 34 per 100,000 people there. In the far less sub-tropical, far more stressful, post-industrial hellhole that is the UK, the current rate of centenarians is, by my calculation, around 23 per 100,000. Okinawans, it is said – mainly by vegans, of course – eat lots of soy products, and this is why they tend to live so long. Robbins has asserted that Okinawans eat 12% of their calories as soy, but it turns out that this figure was taken from a (pork) pie chart of total legume consumption.
Now, to assert that a single dietary element can be responsible for making it past 100 is brave, maybe even foolhardy. One of the authors of a book on Okinawa’s lifestyle and eating asserts that there are genetic factors at work here, which in a small and relatively isolated population typical of an island, is highly likely to be a factor. Then there is the particularly strong sense of community, and the equally strong sense of purpose that pervades the life of the elderly Okinawan, according to studies on them. Let’s not ignore the sunshine, either, and the fact that the main cooking fat there is…lard. Eat lard, live longer. There must be a cookbook in that? Actually, I found this mediaeval translation of a Roman ode to gladiators:
‘En garde!’/As they sparred,/Flexing, working hard,/’Don’t be a retard,/Cook with lard’.
Anyway. So it looks relatively easy to pick apart the argument that it is soy that bestows longevity upon the Okinawans, when there are clearly multiple factors involved, including lard. But could soy contribute to longevity at all? As non-Okinawans, should we be suckers for soy? Or are the touted longevity benefits of soy no more than marketing hype?
The thing is, in Asia, soy has been traditionally consumed in either a fermented form or a coagulated form (tofu), and in small quantities as a condiment rather than a primary nutrient source. These preparation methods offset the inherently toxic nature of soy to an extent. Even so, a disease called Hashimoto’s thyroiditis, an autoimmune disease, was first described in Japan, and seems to be on the increase globally.
So I hereby run through a list of associations and causal relationships made between soy and human health. There have been controlled studies in some areas, for example that of tissue changes in the reproductive organs of babies, where it might be reasonable to infer that soy causes the health change. In others, there is an association in which soy is a likely cause or contributor to the health change.
Soy linked to increase in thyroid cancer in older women.
Soy linked to increase in fatalities in peanut allergy/asthma sufferers.
Soy linked to increase in hypothyroidism.
Soy causes changes in tissues of reproductive organs in babies.
Soy linked to increase in risk of breast cancer.
Soy causes decrease in testosterone levels.
Soy causes decreased fertility – in men and in women.
The vast majority of soy products are soy isolates, in which none of the antinutrients have been nullified, as happens in the traditional fermenting process, yet soy is constantly being marketed as a ‘health food’. It is indeed a health food, a bad health food, and, if you have thyroid problems, reduced testosterone, breast cancer or a peanut allergy, then soy’s contribution to your longevity is likely to be a negative one.
Till next time. ‘Don’t be a retard, cook with lard. It’s neither hard nor ill-starred, no need to be on your guard,’ quoth the bard.*