Soybeans are made into a number of food products, such as miso and tofu in Asia, but in the West, it’s increasingly become an ingredient in all kinds of foods, like veggie burgers. Food manufacturers add a soy product, textured vegetable protein, to many processed foods. Is soy good, bad, or indifferent?
Here’s the truth about soy: the good, the bad, and the ugly.
Soy consumption is associated with a lower risk of cardiovascular disease, enough that the FDA decided that soy food manufacturers could make health claims for them. ” [T]he agency has concluded that soy protein included in a diet low in saturated fat and cholesterol may reduce the risk of CHD by lowering blood cholesterol levels.”
The FDA pronounced their judgment in 1999, but unfortunately the intervening years have not been kind to the data on soy, which turn out to have little effect on blood lipids and cholesterol.
Cholesterol itself doesn’t cause heart disease anyway, so the FDA’s reasoning in this case is spurious.
The good about soy isn’t really all that good.
Soy contains phytoestrogens, which are molecules that mimic the action of estrogen. They’re a class of compounds known as endocrine disruptors, which affect the sex hormone systems of both men and women, and are of increasing concern in the environment. Endocrine disruptors are also found in food packaging, personal care products, store receipts, and plastics, and should be avoided.
If we should avoid environmental endocrine disruptors, it seems a really bad idea to be ingesting them in large quantities.
Soy contains large amounts of endocrine-disrupting phytoestrogens. See table below.
The amount of estrogens in soy makes the use of hormones in meat into a non-issue.
Some studies have found the effects on male hormones such as testosterone to be minor, others have found a larger effect. The larger point, however, is that because phytoestrogens bind and activate the estrogen receptor, they don’t need to change male hormones to have a feminizing effect.
Large amounts of soy can lead to a complete loss of manhood and gynecomastia (man boobs).
Phytoestrogens in soy can disrupt the endocrine system in fetuses and infants, leading to lifelong reproductive problems in both men and women, and can alter the developing brain.(Source.) Consumption of tofu is associated with decreased cognitive function in adults.
Soy simulates the growth of estrogen-dependent breast tumors in a dose-dependent manner, so soy products may cause cancer.
Men who consumed large amounts of soy had lower sperm counts. “In the multivariate-adjusted analyses, men in the highest category of soy food intake had 41 million sperm/ml less than men who did not consume soy foods.”
Soy suppresses thyroid function and is a goitrogen. As someone who’s had hypothyroidism, I can say that you really, really don’t want that to happen.
The Really Ugly
The really ugly part of soy is that Big Food puts it in everything, and as we saw above, the FDA approves of it, and so large numbers of people are consuming large amounts of soy. Could that be responsible for the general feminizing of men that so many have noted?
They even put it in baby food. Baby food, Mandrake.
Textured vegetable protein (TVP) is a waste product of soy oil extraction, so of course they decided to put into food. The food company Archer Daniels Midland invented TVP in the 1960s, and if there’s one thing you don’t want to eat, it’s a food invented by a food manufacturer, especially only a few decades ago. Hydrolyzed vegetable protein is another product often made from soy and found in many processed foods.
Unbeknownst to most consumers, in addition to well recognized soy products such as soy milk, tofu and tempeh, soy is found in upwards of 60% of processed foods. Textured soy protein (50–70% soy protein) is a meat substitute found in hotdogs, hamburgers, sausages and other meat products while soy protein isolate (90% soy protein) is used to enrich energy bars, sports drinks, infant formula, cereals, granola bars, imitation dairy products, ice cream, cheese and even doughnuts. In addition, textured soy protein is used to fortify numerous products in the school breakfast and lunch programs as well as other federal assistance programs. Soy is a popular food additive because it is a cholesterol-free, vegetable protein rich in complex carbohydrates and unsaturated fats, high in fiber, and free of lactose. It also contains upwards of 100 or more phytoestrogens. [Source.]
The Deep Soy State may be metaphorical, but it’s a very good metaphor, with food companies and the government colluding to get it into all kinds of foods.
Avoiding soy and phytoestrogens
Soy and the phytoestrogens in them are widespread ingredients in processed foods, so avoiding soy is both a simple and sometimes difficult task: don’t eat processed foods. Eat whole, unprocessed or minimally processed foods like meat, dairy, eggs, fish, vegetables, and nuts.
I’ve got some more bad news too: beer contains phytoestrogens. It comes from hops, which contain a potent phytoestrogen, and which may be responsible for reported menstrual problems in female hop workers. “Hops have been shown to contain one of the most potent in vitro estrogenic substance known from the plant kingdom, (±)-8-prenylnaringenin.” (Source.) The new style craft beers contain more hops than ever, so they are probably best avoided.
Soybean oil does not contain phytoestrogens, but you shouldn’t consume it anyway. It’s toxic waste as far as I’m concerned, and can cause cancer and heart disease.
The good news is that if you make a concerted effort to avoid soy and other estrogenic substances, any hormonal or sexual health problems such as infertility or erectile dysfunction should return to normal in fairly short order, perhaps weeks to months, depending on initial severity.
So cast off your chains, you have nothing to lose but your man boobs.
Question, does this also apply to non-processed soy products eaten in moderation like edamame, for example? I noticed that most of the problem foods mentioned were highly processed like soy flour, soy milk, tofu, soy additives, etc. I’m wondering if this is a processing problem, like eating whole fruit vs fruit juice or table sugar, etc…
James, according to this article, endame has a fair amount of phytoestrogens. Processing can concentrate them though.
Ok, good to know. Years ago I cut back on soy, but it seems like I didn’t cut far enough; so I’ll completely cut out the processed stuff that I still eat occasionally (tofu and miso), and make edamame a once in a while thing. Thanks.
Thanks for the informative article. I knew that soybean oil was high in omega-6s and therefore best avoided, but I hadn’t realized that soy protein was an endocrine disruptor. To date, I’ve generally avoided foods made with soy, but now I’ll make a point of cutting it out completely.
Laughed out loud at the Strangelove reference. Thank you!
Thanks, Robert – I didn’t know how many readers would catch that!
“Ice cream, Mandrake. Childrens’ ice cream.” I too loved the Strangelove reference. The best movie ever…by far.
Loss of essence.
Hello Mr. Mangan, the following info should be of some interest to you (source: https://www.ncbi.nlm.nih.gov/pubmed/16772450)
The quantity of 8-prenylnaringenin present in beer is actually not as relevant as it might seem – its metabolized into several different metabolites, many of which are also estrogenic (though less so). However, hopped beer also contains a phytoestrogen called isoxanthohumol which is substantially more abundant than 8-prenylnaringenin though it itself is far weaker.
However, when isoxanthohumol reaches the bottom part of your gut, almost all of it turns into 8-prenylnaringenin and you get hit with a high dose of phytoestrogens (contingent on the isoxanthohumol levels in the beer). Relative to straight-up estradiol it’s weak but it is decidedly not biologically insignificant.
Thanks, Theo, that is indeed of interest.
I live in Asia* but have avoided unfermented soy products (tofu, edamame, etc.) for some time. However, it has been my understanding that fermentation (e.g. soy sauce, natto) greatly reduces the phytoestrogens. Is that true, and if so, is it enough?
* People over here actually consume less unfermented soy product than people in the West think, although the “soy as health food” perception and addition of soy to various processed food products is increasing.
This question is something I am interested in also PD. In the past I have avoided soy milk and any TVP added stuff. But I’ve always thought that miso and tempeh were fermented and thus OK.
I also would like to know if bio natto is okay to eat every once in a while? I am not a soy person, but I do like fermented natto every once in a while. Very high in Vitamin K2 (I think the MK-7 type which has the longest half-life). I never eat un-fermented nor non-bio soy of any kind.
Yikes, I had no idea peanuts were so estrogenic! Rather disappointing (and illuminating) for someone who liked peanut butter a lot as a boy.
Interesting to see peanuts on the list as I’ve never heard them mentioned in that context before. Any comments?
Definitely sad to hear about hops. There’s this amazing double-hopped beer brewed by Odell that I really enjoy. Luckily I only get to have it once every couple of years.
Even worse, almost all the soy products from the USA are GMO soy. They are sprayed several times with roundup. So you get cancer causing chemicals along with your Franken food burger and feed chemicals to your newborn; how evil is that? Just treat all soy products as poison avoid them entirely and you will be fine. Eventually they will lose enough money and produce non poisonous products. Gmo soy is fed to livestock, fish, etc so everything that is not organic or specifically grass fed is suspect. How sad that our farmers are too stupid to realize the lies they have been sold.
Roundup is traceable in large amount in cereal, oats etc. There was a large study released this year
PD, Off topic but interesting, you have covered lots of health helping items. But have just found an article in Heart, which talks about the benefits of chocolate for the heart.
It reduces Atrial Fibrillation !
Even sugar rich milk chocolate works apparently.
but I’ll stick with 90% dark just to be sure.
Also check out the info on the Dutch Study. roguehealthandfitness.com/chocolate-prevents-death/
I’m really surprised to hear that soybean oil does not contain phytoestrogens; I figured that it would be the biggest culprit. What do you think about the effect on one’s body from heavy consumption of eggs from chickens on a heavy soy diet?
I’m guessing that estrogens in animals that eat soy would not be a problem, but I don’t really know. Most would be metabolized and excreted, so it would only contain the amount it had eaten recently.
Also, what do you think of the phytoestrogenic potential of soy lecithin? It’s pretty widespread as an emulsifier (almost always used in chocolate production). Always wondered about this one
This article says that lecithin has no isoflavones (phytoestrogens).
Would you keep using whey protein that contains lecithin? Or find a soy free brand to be safe?
Soy lecithin is present in small amounts in protein supplements and contains virtually no phytoestrogens, so it’s not a cause for concern.
I did, at least a year ago, just to be safe. I use Blue Bonnet whey isolate & after tons of trial & error i feel it’s the best whey available on the market… grass-fed, undenatured, and soy free
In regards to soy lecithin:
“Soy is the greatest food source of phytoestrogens, and one group of researchers discovered significant estrogenic activity in soy lecithin. (15) Interestingly, none of the soy lecithin they tested contained genistein, which is the predominant phytoestrogen in soy. They concluded that “a so-far unidentified estrogen-like compound” is present in soy lecithin that accounts for its estrogenic activity.”
It is really too bad about soy having phytoestrogens, if not for that it would be a good source of plant protein. I remember reading that whey and soy protein together are superior for muscles because they contain different amino acid profiles, for example soy contains a high level of the amino acid glycine, which is low in whey.
I used to eat Cliff bars and other energy bars since I travel a lot but have had to stop due to there high sugar and soy content.
This is my favorite line:
“The amount of estrogens in soy makes the use of hormones in meat into a non-issue.”
Indeed! Indeed! And furthermore people are too worried abut BCPs when they’re okay with ingesting tons of soy which is basically the same..makes no sense to me
From the linked study on identification of phytoestrogen in hops:
“The presence of 8-prenylnaringenin in hops may provide an explanation for the accounts of menstrual disturbances in female hop workers. This phytoestrogen can also be detected in beer, but the levels are low and should not pose any cause for concern.”
I wonder what they mean by “low” enough in beer to not be concerned?
Daniel, that’s a good question. IMO, and it’s speculative, is that old-style beer like Coors or Bud probably doesn’t have much in the way of hops, but new style IPAs possibly do. IPAs are loaded with hops, and I’d be careful about drinking too much of those types of beer.
Hi Daniel – See my above content for some more detailed information on 8-prenylnaringenin.
Wait if soy decreases cognitive function and Asian countries consume disproportionate amounts of soy, and Asians still have relatively high avg IQ, does that mean if we substituted red meat for soy in the Asian diet they would become a genius super-race
Thing about Asian soy consumption is that it’s fermented soy – miso, tempeh, etc. – so the bad stuff is fermented away.