Having observed Chinese culture first-hand at close range...
* Yes, they really do eat a lot of soy, and have for a long time. Daufu is the key ingredient in a fairly common dish that has been around for a long time, "ma bo daufu" ("the pockmarked mother's bean-meat"). Soy sauce has been ubiquitously used for probably thousands of years.
* Soy-milk is NOT a by-product of making daufu. You make daufu out of soy-milk. It's not a by-product, but a first-step in the process. First you make soy-milk, then you coagulate it with calcium salts. I dunno how long they have drunk it, and it's true they don't feed it to their babies except maybe fortified, recently, for infants who are already allergic to milk.
Most other Asians do not eat nearly as much daufu, if any, as the Chinese. The Japanese however have been making Miso for hundreds of years, and that is a very common type of soup, which in the old days was a fairly typical Japanese breakfast. Also, large numbers of diaspora Chinese have introduced soy to a lot of parts of the world, such as Southeast Asia, where the natives don't or didn't eat it but Chinese locals do.
Javanese have been making a soy product called "Tempeh" for a long time. It is made by innoculating soybeans with a specific fungus, and eating the soy and the network of mycelium. It is "interesting" for a number of reasons, but hard to make unless your climate has an ambient temperature of around 90 degrees with correspondingly high humidity. People determined to make it in the USA make boxes to keep it warm and humid to grow the fungus, which they need to maintain as a pure culture.
I think a lot of hysteria around soy started when some Italian scientists discovered that a diet rich in soy is negatively correlated with heart attacks.
Unfortunately, they speculated that it might have to do with the phytoestrogens found in many Leguminous foods including soybeans (this is NOT a peculiarity unique to soybeans). Women do not die of heart attacks at anything like the rate at which men do, until about 20 years or so later in their lives when their hormonal levels subside. Problem with linking it to estrogen is that not only do men produce estrogen, but unlike women their production does not fall off as much with age. (hmmm...are eunuchs as prone to heart-attacks as intact males?)
http://www.sciencenews.org/sn_arc97/12_6_97/fob1.htmEstrogen is usually described as the animal kingdom's primary female sex hormone. That's a gross oversimplification, however. Even that quintessentially male preserve -- the sperm -- depends on estrogen, scientists report this week. Without estrogen, males are infertile.
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What the new data clearly demonstrate, Korach states, is the essential role of estrogen in male reproductive health. Indeed, Sharpe adds, "Suddenly, the idea of 'male' and 'female' hormones begins to look thin."
Estrogen is thought of as a "female" hormone only because our way of thinking has been dominated by cultures that tend to view the world as opposing opposites, for example, Aristotelian binary logic, or the El-Ashteroth fertility cult.
Male and female are not "opposites". Put a man and a woman together and they don't cancel each other out and implode!
That article I linked to touches on male hormonal problems that are causing a decrease in sperm count, not to mention a suspected effeminization of men in general. That's an issue to discuss on a different thread, and I doubt it has anything to do with soybeans. To be honest I wouldn't be surprised if the problem were actually with women's hormone's not mens: using birth control pills makes women prefer more effeminate mates. Not to mention that the hormones in birth control pills get into the sewage system and are detectable in drinking water.
In any case, soybeans are not unique in containing phytoestrogens, they have approximately one-thousandth of the effect of real estrogens, and furthermore, most people's digestive tracts break down a lot of what's there before it hits your blood stream.
Unfortunately, though, the Feminist community went off half-cocked over the speculated hormonal link, and widely-disseminated the idea that soy foods were "good for women".
This, not surprisingly, resulted in a counter-reaction that they must be bad for men!
It didn't help that there had already been a deep suspicion of soybeans in some segments of the "whole foods" movement, because soy-foods are essentially ALWAYS fractionated. Almost no human eats soybeans straight up; they're hard to cook and hard to digest.
When I developed sensitivities to certain foods as a result of a problem caused by prescription antacids that I stupidly took on doctor's orders, I stopped eating soy, because it was commonly listed as a common irritant.
Soy is also ubiquitous in processed foods--further damaging its reputation. BUT only in tiny amounts. And I don't eat much processed food anyway. The really hard foods to avoid were actually wheat and oats.
I eventually narrowed it down to the gluten in wheat, to which I had developed a mild sensitivity, and....OATS! To which apparently I have long been developing a sensitivity to and can no longer tolerate at all!
And oats are absolutely ubiquitous in US breakfast foods. Wheat and corn-based porridges have gotten very rare, most brands have been pulled from the markets, and I can only find the few left at just a few stores anymore. It's probably easy to find corn porridge in the southern states ("grits") but it is very hard to find in northern states--mostly only in grocery stores where Afroamericans, many of whom still eat it--shop.
The only thing I notice about soy is that textured vegetable protein is hard to digest. It's too dense, probably has too long of polymerized chains of amino acids, and often show up in a fatty form as "vegetarian meat". Daufu seems to be pretty easy to digest; I have no problem with it and never did.