Wednesday, May 19, 2010

Killer Tofu

This week's "Tip Hero" newsletter contained a link to a tip I wouldn't have considered particularly controversial: "A Cheap and Healthy Meat Substitute." The article was about TVP, an inexpensive meat substitute made from soybeans, and most of the comments focused on ways to use TVP and other soy products. However, one of the comments seemed to wander off into the realm of, well, wacko-dom. An excerpted version:
Arrrggghhhhh, soy?? Has anyone ever read "The dark side of soy"? Soy is actually toxic in the bean form and they acid wash it, and do other nasty things, to make it edible at all. It's used as a filler, just like all the chemicals and such in our foods. Soy washes away all the good stuff in our digestive tracts, plus mimics estrogen in our bodies....Don't believe what they tell you out there, they are not out for our health and the government, the FDA, and the Medical field is all about keeping us sick. The only way "some" say it can be used safely and might have benefits, is when it's "fermented" soy. However, there are still those who will argue it's not safe at all.
Now, I already knew for a fact that soy doesn't need to be "acid washed" to be edible, because I've eaten it straight from the pod as edamame, so I was naturally suspicious of the comment as a whole. It sounded like such blatant pseudoscience that my first impulse was to go to Snopes.com and "The Straight Dope" looking for an article debunking these claims. To my surprise, they had never been addressed. I then tried Googling phrases such as "soy inedible," "soy toxic," and "soy safety," but I didn't find a single article on the safety of soy that seemed to be from a reliable, unbiased source. I found one article by alternative-health guru Dr. Andrew Weil, but I hesitated to cite him as a source, since so many people consider his views a bit "fringe" already. An article from the Mayo Clinic looked promising, but it turned out to be about soy-based supplements, rather than soy foods. Eventually I managed to turn up an article from the NIH's National Center for Complementary and Alternative Medicine, which said only that "Soy is considered safe for most people when used as a food or when taken for short periods as a dietary supplement." (However, it also noted that research is unclear about whether soy can affect estrogen levels, so women who are at risk for breast cancer and other hormone-dependent cancers should "be particularly careful about using soy." It wasn't clear whether "using soy" referred to eating soy foods or taking soy supplements.)

I was surprised at how hard it was to find a single reliable source that evaluated the health risks and benefits of soy objectively. However, one thing I do know is that from an ecofrugal standpoint, the benefits of soy products aren't always clear-cut. For example:
  • Soy isn't always cheaper than meat. A one-pound slab of tofu costs $1.49 at Trader Joe's. A pound of chicken or pork can cost a dollar or less on sale at the local Stop & Shop. (Free-range chicken, on the other hand, starts at $2 a pound.)
  • Tofu isn't a particularly lean source of protein. According to the USDA's National Nutrient Database, half a cup of raw, firm tofu has about 20 grams of protein and 11 grams of fat. A whole cup of white-meat chicken, by contrast, has 27 grams of protein and only 4 grams of fat. (Hardly surprising, when you consider that soybeans are grown largely for oil.)
  • On the other hand, soy does seem to come out ahead from an ecological standpoint. According to Wikipedia, soy farming produces "up to 15 times more protein per acre than land set aside for meat production."
On the whole, including soy foods in my diet seems to be a reasonably ecofrugal choice, and the balance of the evidence suggests that it should do my health more good than harm. But I can't help wondering whence comes all this animosity toward the humble soybean. Are all the anti-soy sites secretly funded by meat producers?

EDIT: Here's a little illustration supplied by Brian to go with this post.

5 comments:

  1. A couple weeks ago there was an article linked on boing boing talking about how certain meat substitutes get processed with hexane and how no one tests to see how much of the chemical remains afterward. Then it was retracted. Then it was reissued. I'll see if I still have the link somewhere in my email dump.

    There has also been talk about how the health benefits of soy mostly come from unprocessed soy - edamame - rather than processed soy (the stuff that bumps up the protein contents of just about everything, tofu, etc.)

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  2. Got this response from Tim by e-mail:

    "It does not really surprise me that there are
    conspiracy theories growing up around soybeans. Various health nuts (including my own physician) have been extolling the virtues of tofu for decades, in many cases claiming that it has a modest fat to protein ratio. If false
    negative claims about its health are springing up now, it seems to me to be a natural reaction to many years of false positive claims."

    My comment: saying that tofu has a "modest" fat to protein ratio may not really be out of line. It has about half as much fat as it does protein, which puts it ahead of hamburger (13 grams fat, 18 grams protein in an average patty) and on a par with pork (12 grams fat, 22 grams protein in a 3-ounce serving). Of course, you can choose leaner cuts of meat, but you can also choose reduced-fat tofu. And many other soy products, like TVP (the stuff that started this whole debate in the first place) are much leaner.

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  3. "There has also been talk about how the health benefits of soy mostly come from unprocessed soy - edamame - rather than processed soy (the stuff that bumps up the protein contents of just about everything, tofu, etc.)"

    Funny thing is, this person on TipHero was claiming just the opposite--that only fermented soy is safe to eat, and that unprocessed soy is not only less healthful, but actually deadly. This is patently false, of course, but some people refuse to be deterred by facts.

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  4. I wonder if any of this fear mongering has to do with the fact that soy receives a ton of subsidies and is lumped with big, bad, evil corn? I love me some corn, although I could do without the heavy subsidies and freaky "grown in a lab" foods and by-products of soy and corn.

    In other news, thanks for stopping by and commenting on me ol' blog! Always great to find a new corner of the web dedicated to earth-loving, frugal living.

    Well, except for TVP. That's a by-product I actually dig. I'm pretty sure my Trader Joe's soy chorizo is made from TVP and that stuff is so good, I could bathe in it.

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  5. Ooh, yes! Eeeeeevil corn! As if it were the plant itself that planned to take over the world....

    I don't think TVP is a by-product, exactly. That is, I think it's a primary product. There's only one company that makes it, I believe. And it is very useful and versatile stuff. Hmm, soy chorizo, you say? I'll have to try that.

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