Marks Daily Apple
Serving up health and fitness insights (daily, of course) with a side of irreverence.
22 Jan

Scrutinizing Soy

You’ve heard me comment here and there about Big Agra’s favorite legume, but I thought it was time to truly sit down with soy, stare it in the eye and get to the bottom of its real intentions.

Just so you know, we had an amicable exchange, and both parties came away from the table having learned a thing or two about open-mindedness and media frenzy.

It’s true, soy was once nutrition’s sweetheart. It could do no wrong (much like multi-grain anything these days). Within a shockingly brief period, it was thrust into the limelight, granted liberties it wasn’t ready for and didn’t, in all fairness, ask for. Its sudden fame propelled it into the likes of the dairy aisle, the barbeque line-up, even infant formula. Talk about big shoes to fill! Could anyone truly stand up to such phenomenal pressure and responsibility?

And so we find soy in its current circumstances, dissected by the health media, floundering, searching for a center long ago obscured, grasping for its authentic, legitimate role in nutritional balance.

All right, I’m ready to heave. Still with me? Just know that I’m completely serious about the media food frenzy, pun intended. Nutrition should be treated with more rationality and common sense than the parading line of fads and momentary cult worship. Maybe that’s what’s so satisfying about the primal diet: it doesn’t get any more basic than primitive.

Anyway, let’s get on with things and break it down.

Soy and Processing
The mantra applies here as well. All together now: Eat food, not food products. This doesn’t mean you have to forgo all forms of soy, but I’ll just say up front that food products with “the benefits of soy” conveniently added in just aren’t convincing me.

As I’ve said before, soy really needs some form of preparation before it’s safe to eat, and that in and of itself gives me pause. That said, minimally processed soy forms like fermented tempeh and miso as well as edamame seem like preferable options.

Soy processing isn’t a very comforting picture with acid washing and neutralization solutions, large and leaching aluminum tanks, and high temperature heating (rarely a good thing in the food world). And this doesn’t take into account the artificial flavorings, including MSG, that are oftentimes added to improve flavor. (Hmmm. When we say healthy tastes great, we kind of mean a food itself and not all the chemical crap added to it. No?) Finally, it’s vital to go organic when it comes to soy. Not only is it nearly all genetically modified, it has one of the highest pesticide contamination levels of any crop.

Soy and Cancer
We’re talking mostly about breast cancer here. The culprit in question is the group of soy isoflavones, plant hormones that mimics estrogen in the body. Some research has shown that isolated isoflavones, a.k.a. phytoestrogens, contribute to the growth of tumors in the breast, endometrium and uterus.

It essentially comes back to the whole foods question. The research has focused on the isolated isoflavones, particularly genistein, the most active of the soy isoflavones that activates cellular estrogen receptors, including those in breast tumors. Noted experts in the field have cautioned that research with isolated soy compounds does not necessarily carry over well to the effect of the whole food, even minimally processed soy flour. In other words, soy is healthier than the sum of its parts. Other studies have shown that the mix of phytoestrogens in soy, when taken together in whole soy foods, protect estrogen receptors and may partly shield them from the estrogen we take in with meat and dairy consumption (yup, bovine hormones even in organic). They can also possibly reduce the impact of the unequivocally insidious “xenoestrogens” found in chemical pollutants.

Add to this picture the analysis of cultural diet and disease trends. Though Japanese women regularly eat significant portions of soy (in forms like tempeh, edamame, miso and tofu), they have only 1/5 of the breast cancer rate that Western women.

Soy and Thyroid Function
Researchers are in general agreement that people with previously diagnosed hypothyroidism (underactive thyroid) should not take soy supplements. There’s not as much agreement, however, about soy and diet. The isoflavones in soy inhibit thyroid peroxidase, which produces T3 and T4, which can make a bad situation worse for those with diagnosed hypothyroidism or, as some suggest, help cause hypothyroidism to begin with.

It’s also important to note that soy isn’t the only food that has goitrogenic effects. Other foods in this category include (but aren’t limited to) cruciferous vegetables, corn and lima beans.

Soy and Mineral Absorption
Soybeans are high in phytic acid, which is known to block the body’s absorption of minerals such as calcium, zinc magnesium and iron. (Pertinent Insertion: grain-based diets have been shown to do the same thing.) Nonetheless, soybeans have the highest level of phytates. Fermentation is known to substantially reduce phytate levels, which is why you often hear that fermented soy forms are preferable. Other sources note that a meat or fish accompaniment to soy will reduce the effects of the phytates.

Bottom line…
Whole and fermented soy forms are clearly preferable. Personally, I wouldn’t bother with anything else. I know all of you soy milk lovers cringe when I say that. If you recall, I acknowledged a while back that organic and unsweetened non-GMO soy milk probably wasn’t a worse choice than regular cow’s milk.

I think there is something to the benefits of whole soy, and MDA has cheered and endorsed tempeh and miso more times than I can likely remember now. Not only do we endorse fermented food around her, but we appreciate the smart protein and blood sugar stabilization of tempeh.

Nonetheless, I’m still mindful of common soy concerns. I question the need for soy supplements, and I’m unequivocally against soy in infant formula (at least a whole entry unto itself!). For healthy adults, however, I acknowledge that soy can have a legitimate place in a well-rounded diet.

You’ve got my take now. What’s your thinking on soy? Shoot me a line.

Kanko* Flickr Photo (CC)

Further Reading:

Tempeh, Natto, Tahini Hurrah!

Spoutin’ Off on Veganism (Again)

Eating Fabulous: Soy May Help in Weight Loss

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Imagine you’re George Clooney. Take a moment to admire your grooming and wit. Okay, now imagine someone walks up to you and asks, “What’s your name?” You say, “I’m George Clooney.” Or maybe you say, “I’m the Clooninator!” You don’t say “I’m George of George Clooney Sells Movies Blog” and you certainly don’t say, “I’m Clooney Weight Loss Plan”. So while spam is technically meat, it ain’t anywhere near Primal. Please nickname yourself something your friends would call you.

  1. Keep in mind – not all beef contains exogenous hormones.

    Yet one more reason to buy from family farms and the small producers that don’t advertise beyond word of mouth or small nickelnik type local classifieds.

    Laurel wrote on July 6th, 2010
  2. My daughter is allergic to cow’s milk proteins, so the allergist suggested soy milk. I had figured we’d be doing almond or rice milk (due to articles like this) but both he and my daughter’s regular pediatrician said soymilk.


    So, I guess at least we buy the kind with calcium and DHA, since I can’t give her fish oil, but still. These articles are tough to read.

    Michelle wrote on September 5th, 2010


    bob redford wrote on June 18th, 2011
  4. I read the Vegetarian Myth by Lierre Keith on Mark’s suggestion. He did a book review..i think his first on MDA. Lierre writes briefly on Soy for a few pages in the Nutritional Vegetarian Chapter and the things that she says will make me avoid Soy completely for the rest of my life. Its interesting to hear the positives and negatives regarding Soy and now with this post im left confused, I figured Mark would have the same info that Lierre has and wrote about and would be telling everyone to run away from the stuff. Anyways even if there’s only a litle truth to what she said im still staying away. I strongly suggest all vegetarians and Vegans read her book. I think she wrote it for them anyways.

    linsben wrote on September 1st, 2011
  5. sigh. so now “primal” is “paleo but..” it’s ok to eat rice, dairy, take whey protein and it’s ok to eat soy. So the next time someone says to me “Primal is just atkins” I’m forced to say…well yeah, it’s all about counting carbs. Hell the founder of “primal” even puts refined sugar in his coffee, eats chocolate and drinks whine…yup, just like our ancestors did.

    Garbage wrote on November 17th, 2011
  6. Well after reading about soy, Iam very worried. I am drinking Herbalife shakes twice a day as a meal replacement for weight loss and the first ingredient is Soy Protein Isolate. Is this something that I should stop drinking and just eat non processed foods? I would appreciate any opinions…

    Maria wrote on February 1st, 2012
  7. Great article Mark…I knwo it was written sometime back but I got to it by following one link to another from today’s post. (LOL) You pretty much summarized everything I have read from the many health resources I read. Did you mention, however, that as a plant, soy absorbs more trace metals from the ground than any other plant in the plant kingdom?
    For Denise and others looking for soy milk alternatives – my family has fallen in love with almond milk. Caution – watch ingredients as one brand I came across has soy with the almond milk. Michelle – the medical field recommends soy milk as they don’t know any better. They don’t have time to read the latest research as Mark presented here. Soy is in the top 5 of allergenic foods.
    An interesting side note I read this past week, and I wish I could remember which doctor’s e-zine I got this from – but for infants on soy based formula – a day’s worth of “meals” is equivalent to a baby taking 5 birth control pills. Soy formula is banned in the UK. Go figure. In three years studies show the average age of menses for a young girl will be 9 – that is downright crazy! Thanks for spreading some truths about soy…I cringe everytime I see someone grab a carton of unfermented, non organ soy milk. Re soy protein isolates- highly acidic food and had additional detrimental effects as well. For vegan protein look at pea protein isolates, but whole foods are always best!

    Rita S wrote on February 1st, 2012
  8. An impressive share, I just given this onto a colleague who was doing a little bit similar evaluation on this. He in reality bought me breakfast because I discovered it for him.. smile.

    bike clothing wrote on February 15th, 2012
  9. Here’s a great link on the harming effects of soy!

    Pranay wrote on February 19th, 2012
  10. Can someone please post how to tell from a package if it has the bad soy in it? I understand that If I grew a soy plant in my own back yard and did not use pesticides/herbisides etc. I could eat the beans and that would be the very best way to ingest soy. However, I would like to continue with a natural protein shake that I take for breakfast. I currently use soy based. I have used whey but I don’t want the dairy. I know that there are others such as rice based, but honestly there are more soy based drink shakes than anything else. Can someone please tell me if any of these are ok according to the standards set in the above articles and comments?

    Karen wrote on April 7th, 2012
    • Foods labeled “organic” are not allowed to be genetically modified, so if your soy option is organic, you will know it is not GMO, at least.

      Along those lines, what does everyone think of sprouted soy, like in Ezekiel breads?

      Nicole wrote on April 15th, 2012
  11. soy is probably 2x as good for you as wheat because its 2x older right?

    Max@flavortogofast wrote on November 4th, 2012
  12. Unless soy beans are proscribed in this plan, I don’t understand why I shouldn’t continue to make my own soy milk and tofu from them.
    Granted, they are not a whole food but they are high-protein/low carb (since the fiber and carbs are left in the bag when you squeeze out the milk.
    The resulting “okara” is something we’ve used in other recipes so nothing is lost and, while we don’t eat the whole bean in a single serving, we still use it all.

    Is there a good reason to stop doing this, or is it basically “you’re on your own either way?”

    Cee wrote on November 8th, 2012

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