A problematic report on the 'dangers' of soy

There was a report in yesterday's Guardian about the supposed dangers of soy products. I am rather dubious about the claims, simply because some of the 'facts' stated about the use of soy beans in Asian cuisine, or Japanese cuisine in particular, are just plain wrong. The implication made in the article is that all soy products are fermented for a long time in Japanese cuisines, but this is simply not true. Only miso and soy sauce and like products - which are only consumed in very small quantities, since they are quite salty - fit that description.

Here is the ways that, as far as I know that soy has commonly been consumed in Japan for hundreds of years, and how I grew up eating them in a Japanese household (and I do mean a Japanese one, in Japan, not hyphenated-Japanese).

  • As tofu. The way that tofu is made is not described correctly at all in this report:
After the long, slow boiling of soya beans in water to eliminate toxins, a curdling agent was added to the liquid to separate it. The curds would then be pressed to make tofu and the whey, in which the antinutrients were concentrated, would be thrown away.

If soy beans were cooked for a long time, they turn into the consistency that any cooked dried beans turn into - mealy and starchy - thus making it impossible to express soy milk from. As far as I know soy milk for tofu is made the way I described it in my how to make tofu series, by soaking the beans then grinding them up before cooking the resulting pulp for a relatively short time (less than 30 minutes) to produce soy milk. The whey is usually thrown away, simply because nigari, the coagulant, has a bitter taste. However, some Japanese households used to save the whey for making the next batch of tofu.

  • As various tofu-based products: aburaage, atsuage, yuba, etc. Also various foods made from tofu such as ganmodoki.
  • As natto, which are boiled and fermented soy beans. They are not, however, fermented for "a very long time" as the article at one point states all soy bean products are, but only for a day. (My grandmother used to make natto at home, fermenting the beans in the warm kotatsu, a heated covered table.) Tempeh is also only fermented for a day or so.
  • As cooked whole dried beans, often together with hijiki (a type of seaweed), or mixed with steamed rice (daizu gohan, or soy bean rice). This goes against the quote from one of the interviewees, who produces soy sauce - "I never saw soy beans on the table in Japan - they're indigestible." Raw soy beans are indigestible for sure...so are all raw dried beans. I have to think he was misquoted somehow, if he really did live in Japan for 18 years and has a Japanese wife. Of course it's possible his wife's family never served whole cooked soy beans or natto for whatever reason. In my experience, it's never, ever a good idea to rely on the anecdotal 'evidence' provided by non-Japanese people who are married to Japanese people and base all of their "Japan expertise" on their interactions for their spouse and their family. This is a typical example.
  • As green immature fresh soy beans, boiled - edamame. Since I originally wrote this post back in 2006, edamame have become almost ubiquitous in many American cities. In Japan, edamame are eaten as beer snacks and such all the time, especially in summer.
  • Finally, as miso (and miso-like bean pastes) and soy sauce; both of these items are fermented for a long period - a minimum of 6 months in most cases, or longer. So, these products are the only ones that actually fit the definition of 'safe' soy products, according to these alleged researchers.

Missing from the list is soy milk, which is called to-nyu in Japan. Traditionally people didn't drink soy milk in Japan; it's just in the last two or three decades that it's been touted as a healthy alternative to milk. When I was going to school in Japan, our school lunches always had a bottle or carton of cow's milk. Most people in Japan still drink cow's milk rather than soy milk.

It's quite possible that industrially produced, highly processed soy products are not necessarily good for you. In my opinion, it's always a good idea to question and investigate just how good manufactured and engineered food products are for you - although for the record, I am not one of those who dismisses GMO products and such out of hand just because "it's evil". Soy products that have been consumed for hundreds, if not thousands, of years, or the whole soy bean such as edamame and cooked dried beans, are another story. Anyone who consumes a disproportionate amount of heavily processed foods of any type to excess is playing fast and loose with their health anyway! However, the items listed as facts in the report really aren't do make me skeptical about the veracity of the whole piece. And is soy milk, which is cooked, bad for you? I'm skeptical about that too.

Although Japanese use of soy was used as the primary examples, the article also made a blanket statement about all Asian cuisines. If you're Asian, what did you grow up eating? What about soy milk, which seems to be the primary focus of criticism?

Update: February 2011 - Another take on this subject over on Calorie Count, which is part of About.com (link updated April 2016).

Filed under:  essays japanese legumes ethics philosophy

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I don't think you've been entirely fair to the article...

Their main point was not to say that Japanese styles of eating soya were problematic but that they showed how much care needed to go into eating soy whereas modern soy food (burgers, milk etc) has only been processed to split it into oils, proteins etc without regard for the toxins and oestrogens.

Christopher Dawson, the guy who lived in Japan for 18 years, runs Clearspring (http://www.clearspring.co.uk/ - website being updated at the moment though) which is the best source for Japanese ingredients in the UK as far as I have been able to find, he used to work for Mitoku in Japan. The Clearspring Organic Mikawa Mirin is truly wonderful.

The article does get some facts wrong about Japanese cooking, no doubt, but their general point is that Japanese soya use is generally done with appropriate cooking and moderated consumption. Western veggies are eating toxin-laden soya in chillis, burgers, sausages, pseudo-cheeses and in 'milks' and 'yogurts'. This is not good.


I have an interesting link about soy here:


It was given by a vegan blogger to answer people worried about soy.
I don't know who is right or not in this "soy" controversy but I think the article is interesting.

These kinds of "reports" enfuriate me.

I am sure if soy products were as harmful as these people would like to claim, the entire population of Asia would have died out centuries ago from consuming so much evil vile soy!

On the contrary, many many studies have shown that Asian peoples, nameley the Japanese, have the highest health and longevity in the world. I would think it would be obvious that a high soy diet has something to do with it... not the opposite.

"Toxins" is really pretty misleading. They don't say which specific chemicals in soybeans are "toxins", and the article is careful to associate that word with isoflavones and estrogen-like compounds. Estrogen is not a toxin, tho having too much can be quite harmful to males. Males are somewhat likely to have bodies that process the estrogen-like soy compounds as estrogen. It'd take a *lot* of soy to give a female side effects from too much estrogen. Further, the estrogen-like compounds in soy don't get processed as estrogen by females (usually, humans vary a lot so there may be some females who would process it as estrogen). Isoflavones are also not automatically toxic.

Please note that describing soy as being like "eating 5 birth control pills a day" is highly misleading. If that were true, you'd expect to see dietary disturbances (vomiting, nausea), reduced fertility in females with high soy product consumption, and a whole host of other effects. Some males do experience symptoms where their bodies exhibit more feminine traits if they have high soy consumption, but this is not something that happens to all men who eat soy.

So it *might* be worth getting hyped over soy, but that article is no reason to. If they'd named the compounds they considered toxins, I might take it more seriously.

We never ate much soy growing up in my Chinese family. Then again, we probably didn't eat a typical Chinese diet in the US. :P My mum doesn't think soy is good for health. She's not a fan of dairy either, so I rarely drank soy milk or regular milk growing up. ...But I think I came out alright. Maybe. .___.

My mum thinks a lot of things are bad, but to me it's ridiculous to think any one food with a long history is super evil or else, as Lea said, people wouldn't have been able to live on these foods. (Not that being alive necessarily equates to health considering how many people die in hospitals, but...you know what I mean.) My mum will tell me how bad wheat is...and then eat a buttered croissant. Argh!

On the opposite end of the "THIS FOOD IS SO EVIL!" scale, some foods get over-exposed as being a miracle cure for everything. Surely there are foods that are known for being healthy/unhealthy, but no single food will erase disease and unless I'm presented with double-deep fried toxic sludge I'd rather not freak out too much about how harmful something is. ;)

I did read the original article, and I am still a bit confused. The article looks to me as being pretty sloppy slapped together. It could be that it has been written by a decent science journalist, but then butchered by a not so knowledgeable editor, or it could have been that the journalist simply did not really know what she was writing about.

About Dawson: I have a suspicion that he got seriously misquoted (the more favorable for him suspicion...).

However, the description of the soy milk/tofu production does not make much sense at all. As said, cooking the beans for a long time simply creates a mush, and on the other hand, boiling the beans in water for extended times will make sure that the (valuable) amino acids get cracked. Which means that the "healthy" substances are simply gone (and one can assume that the oestrogen-like compounds will get cracked too.

It is understandable that such imprecisions in the article hurt the credibility of the rest (which might actually be correct).

One thing can be interpreted into the article, and that is that highly industrially produced products may be questionable.

Ah, yeah, about soy milk... to claim that it is "good" needs some kind of "special" palate ... I personally hate that hayy flavor.

I grew up eating lots of tofu and drinking soy milk (the Vitasoy box drinks!) on occasion too, though my Chinese American family normally drank regular cow milk at home. The thing about how tofu is prepared in Chinese restaurants & kitchens is that it's often fried, much like aburaage... I hardly ever get to eat it cooked well in its fresh state, though I suppose that this is done mostly in the home (my grandfather cooks cubes of fresh tofu with frozen peas... this isn't very tasty though.)

As for soy milk, Chinese folks seem to like it sweet, a la Vitasoy -- and all of that added sugar can't be good for you!

Jason: I think that the article is very sloppily written and researched (or perhaps, as max suggests, poorly edited). This distracts from its message. It's quite surprising, given that it comes from the Guardian, which is maybe my favorite UK newspaper. It's not measured and I found the writer's range of interviewees and research to be quite inadequate too. As you say, she probably is making the point that industrially produced soy products are dangerous but the message is lost in the mire, in my opinion. As Emily says, some terms were thrown about too lightly, like the birth control pill thing.

Robyn: I wonder why your mother thought soy was not good - or for that matter milk?

plume, thanks for that link! I'm going to put it in my next post so people who don't read comments might see it too.

Maki - Agreed it's a sloppy article and I'm probably giving them the benefit of the doubt because it is The Guardian who are usually very good (about the only paper I can read apart from IHT without getting fed up).

Maybe she thinks there are better foods out there that could replace tofu and soy...or that they're not that needed in general. I'm not a big fan of plain milk, but I don't mind it as much now as I used to. In 9th grade I gave a presentation about why milk is bad and my class thought I was insane (thankfully, my teacher didn't). I doubt I would choose a topic like that today as I don't think milk is really bad or awesome (I got sick of "Got Milk" ads after seeing a gazillion of em over my lifetime). It's...useful. And it's good for cheese and ice cream. :] If I could, I wouldn't mind trying milk fresh from the cow, although I suppose a lot of people would find that more disgusting than regular factory made milk, stuff that kinda grosses ME out.

Fresh milk from a cow is unbelievable.

When my sister Mayumi visited Switzerland, she couldn't stand the regular (full-fat), fresh milk because to her it tasted like cream. She had gotten too used to drinking watery skim milk...

You forgot to mention the spate of crank articles about how all Asians are supposedly lactose intolerant that are popping up in the U.S. media. As you mentioned, every school lunch in Japan since MacArthur has featured milk, and kyuushoku blogs have now popped up all over the place documenting that fact.

Soy milk does seem to be rather more popular these days, but it's still maybe a 5-to-1 ratio, judging by shelf space in the markets.

I think the Japanese experience puts the lie to all the soy danger hysteria, as it does to the mercury-in-fish hysteria.

Toxicity is not just about the chemical compound per se, it is also about dose, duration and the unique response of the individual. Lea is correct; isoflavones are not toxic just because they are isoflavones, however but they do illicit estrogenic effects at doses that are readily achieved from consuming soy. That is why there is much evidence that shows that dietary exposure to soy isoflavones causes infertility in all manner of experimental animals and can markedly alter the menstrual cycle of adult women.

What really troubles me is the massive amounts of the isoflavones that infants fed solely soy formulas are exposed to. You see here we have a situation were we have a potentially toxic compound coupled with large dose, long duration in highly susceptible targets. Sad to say the "5-birth control pills a day" is true; it refers to the amount of estrogenic equivalency that infants fed solely on a soy-formula are exposed to. That the soy industry can continue to expose infants all over the world in such as way when they have the ability to remove isoflavones from soy formulas is unforgivable.

But isoflavones are not just estrogens. It is little known that the soy isoflavones are also potent anti-thyroid agents, more potent that the drugs that are given to people with hyperthyroidism. In fact isoflavones are best viewed as naturally occurring endocrine disruptors. They are present in the soy bean for one reason – to stop things eating them! Adults would be wise to eat soy products in moderation and even wiser to minimise isoflavones exposure in infants, children and adolescents.

Thank you, mike, for this information. I'm new to some of this, having very recently had breast cancer surgery (I'm 70, with no family history of it). One of the concerns is that if you test as "estrogen receptor positive," other substances that mimic estrogen (such as soy) could be attracted to these sites with adverse results. I'll update this in the future as I find out more. The point is that some may be overdoing the soy use -- too much soy milk, tofu, etc. -- thinking it's "good" for them. I drank milk as a child and adult, never tasted soy milk (knowingly), but use shoyu once or twice a week in stir frys for the past 10 years or so.

October is Breast Cancer Awareness Month in the USA. Dr. Susan Love, a well-known expert in breast cancer research, has started a website ArmyOfWomen.org to try to sign up a million women of all races and nationalities, young and old, diagnosed with breast cancer and HEALTHY, to take part in a huge collection of data. Breast cancer may be caused by a virus or some other factor. Instead of only treating the disease once it's diagnosed, Dr. Love hopes to find other common factors from among healthy womean as well.

To register for this on the website, you supply your name, email address, Zip code (where applicable), race (general), and create a password. Later you can supply as little or as much additional information as you choose.

The website is better at explaining this than I am. Please visit it and do as you think best. Dr. Love has the right idea and needs far more data than is otherwise available to try to track this down. We all can help -- without revealing personal identifying information. Everyone will benefit.

Very late to the discussion, but anyways.... In Singapore and Malaysia, soya bean milk (dou-nai 豆奶) is a very common drink. Although there are plenty of canned or packet commercial varieties, it is also commonly sold freshly made, alongside beverages like fresh fruit juices, and another local fave, fresh sugarcane juice. I love my soya bean milk, steaming hot and fresh from the pot. There is that stomach warming, thick and soothing factor not unlike cow's milk, but without the lactose which I can't take too much of. At my favourite soya bean milk stalls, the sugar syrup is added just before serving, so you can ask for less, or omit the sugar altogether. You can drink it plain, or do the Taiwanese style and dunk deep fried dough (you-tiao). Other interesting variations on the standard bean milk you can choose from include ginger, chocolate, almond, and chinchow (a black-coloured herb beverage with julienned herb-infused jelly - the black wormy things make an interesting contrast with the white milky soya bean milk) Soya bean milk has always been seen as a healthy drink here - it is commonly believed that it in fact detoxes (!) I've heard accounts of factory workers, whose work causes them to inhale alot of smoke/dust, swear by their daily dose of soya bean milk to detox.

Being a science student we've been told at uni that most if not all scientific newspapers/magazines/media for the general public tend to be misleading; let alone non-scientific sources reporting on scientific discoveries.

Public media usually spruce up "reports" making them a better read for the general public, the n.b. JOURNALIST (not scientist; they have not much scientific background, if so, probably not in the area that they are reporting on) misinterprets the information given or just the fact that they tried using analogies to explain a difficult scientific phenomenon but in the end having it come out all wrong.

When the public think of the scientific magazine "New Scientist" most would ohh and ahh thinking its all true to the bible, but in fact that they information presented may not ALL be true; it may be based on some facts, but really its a magazine. Within the biological science school (dont even think about the med faculty) "New Scientist" is just entertainment to us.

We students would get smacked if we try to cite something from a science magazine and if you try telling anyone who knows their stuff that everything in a science magazine if true; u'd just get laughed at.

Want some real up-to-date science info? Try a science journal paper and dont forget to check the Impact Factor. >_>"

Like klOOK, I'm from South East Asia as well. Tofu is one of the soy things seen at our mealtimes (I can't think of any more, actually). But we don't cook it everyday. My family isn't that big a fan of tofu, so we have it maybe twice a month? Unless you eat out and love tofu so much you'd order it everyday, I doubt people eat much soy in their meals.

The other two soy products that are consumed are soy bean milk and "tau foo fah", which is a dessert that's rather like silken tofu, but much softer. Again, these things aren't drunk or eaten everyday. Maybe once a week, or once in a blue moon for certain people (like me).

Over here, soy bean milk is seen as just another type of drink, like Coke or Pepsi. I've never heard anyone mention the health benefits of soy bean milk; they drink it because they like the taste. And most people I know don't drink it that regularly unless they like it very much and have a craving for it every other day. Personally, I don't like the taste of it so I don't drink it at all. ^_^;

I find that it's not uncommon for people (especially in the United States, where I'm from) to release articles about how dangerous certain trendy foods are. American journalists make money off of claiming outrageous things, so when I see articles like these, even though it's from the UK, I just go, "eh" and continue on about my day. I am allergic to dairy and soy milk has more protein than rice milk and is less expensive, and thus it's my milk of choice. I'm pretty sure I'm not going to die from drinking it.

I also think that Western cultures should probably be more concerned with the health dangers of things like Coca-Cola and artificial sweeteners than they should with time-tested foods like soy. ;)

Thank you Mike, I couldn't have put it better myself.

As far aa I'm concerned soy is a very dangerous product when consumed in the quantities that vegans and some vegetarians eat it. It's actually very concerning as they have bought right into the soy industry's hype of soy being marvellously good for you.

The facts are otherwise. But you'll need to look at the scientific research to understand exactly why.

For starters, try this website: soyonlineservice.co.nz

and read the scientific research there amongst other informative articles you'll find.

Aside from the very high phytic acid content of soy, which robs the body of minerals, there is the effect that regular consumption of soy has on the thyroid gland. And that's just the beginning of soy's unpleasant activities in the body.

There was a time when I too bought into the BS that soy is very good for you, and I happily ate tofu almost every day. The result of all those phyto-estrogens? Massive haemorrhaging and a total disruption of my hormonal balance.

I learned the hard way that it's always better to do your own research rather than pass uninformed opinions or become defensive.

That site does not look like a legitimate or reliable source of impartial information to me by any stretch of the imagination.

The whole point here is that should be taken into account is that excess consumption of ANY single nutrient could conceivably - not definitely - lead to some kind of harm. I don't know if this is some sort of modern malaise, but there is this almost hysterical tendency for people to rush to one kind of 'miracle food' or another, based on sketchy theories; or on the other side of the coin decry some foods as being poison, etc. This doesn't bode well for our future.


I used to work in a "health food"/natural food store and I heard the BS about soy being "evil" many, many times. (I'd like to point out, FTR, that the 'recommended alternatives' to soy products all cost at least a few dollars more. As if I'm supposed to believe that didn't have anything to do with it!)

I loved to point out Asian cultures' love of soy as an argument against the 'anti-soy campaign'.

Personally, I DON'T think "soy" has anything to do with it- however, when westerners consume soy (ESPECIALLY the 'health conscious' westerners frequenting whole food stores...) it's not as a whole soy product (edemame, miso, soy sauce, tempeh, tofu) it's as "soy protein isolate" (in shakes consumed as meal replacement- so instead of sitting down for actual food, these people will drink a shake made of chemically separated soy byproducts and vitamins...) "fake meat" (Tofurky anyone?) and other outright abuses of the humble soybean- consumed in great quantity. As in, "instead of normal food."

I suspect that if you did these very same things with oh, say, organic broccoli, you'd have similar problems. I continue to happily eat soy and don't worry about it. :)

I'm a 19 year old and my periods have been regular as clockwork since I was 13 and I love soya milk. Women have so much oestrogen that a little bit of soya milk would be a drop in the ocean.

I resent the post that suggests that ALL vegans eat fake meats. It's an ignornt generalisation. Many vegans nver eat soya products at all and most of us avoid fake meats - why wuld we want something that tastes like death?

I've known someone who was allergic to soy, and as a result his food choices were very limited. There is soy in nearly every pre-packaged thing you buy from the store. I don't think it's so much a matter of whether or not you drink soy milk or eat tofu, but a matter of eating a variety of good and nutritious foods - soybeans included!

Regardless of this debate, there is one thing about soy that is not up for debate: it is 1 of the 8 most common food allergies (milk, soy, eggs, wheat, peanuts, tree nuts, fish and shellfish). So despite everything else, it is safe to say that the human digestive system does not respond well to soy. What infuriates me is the fact that soy is in EVERYTHING! As someone who is sensitive to soy, I hate that it is shoved in my face all the time as this super food, because for me, super food it is not. It is like a toxin in my body. Guess what, Soy Milk can be just as, if not more, irritating than regular milk! Get it out of my face!

People also always make the Asian claim. The Japanese and Chinese eat 10 grams of soy per day — about two teaspoons. Yet a soy manufacturer recommends Americans eat ten times what the Japanese eat — 100 grams of soy protein per day. Soy production in the US is going gangbusters and these mega-industries are shoving it down our throat. Also, the fermenting of soy in Asian cuisine cuts the harmful properties of soy.

People with Thyroid issues are instructed to avoid soy, as are people at risk of breast cancer. If soy is so great, then why would this be?

To me, after watching many infuriating food docs and getting worked up over industrialized food practice in the US, I've realized that things like corn and soy are taking over our diets at rapid rates without much research into the effects on humans. Like I said, it's going gangbusters, so they market the hell out of it and have the money and power to squash any dissension. To me, this is what is really alarming.


See the centre for science in the public interest nutrition action health letter for reliable research based nutrition info with no hype, they have no advertising

After concern about soy being problematic, I didn't eat tofu or any soy products for several years (except shoyu or tamari, since it is well-fermented and is only flavoring). I did start eating tofu again though since I heard some contrary evidence to the anti-soy (i.e. that phytoestrogens actually *block* estrogen receptors, leading to a *decrease* in cancer). I still wouldn't eat highly-processed soy, such as soy protein isolate or "textured vegetable protein" (TVP), as it is sometimes called. I also wouldn't eat non-organic soy because it is essentially always transgenic (aka. GMO) and I don't trust GMO products (in addition to avoiding pesticides.

Macrobiotic folk say you should eat soybeans but not tomatoes, potatoes or eggplants (which are nightshades).
Some Buddhists, Hindus, and Jains (especially monks) avoid onions or garlic in addition to meat. Then we have the "paleo" people who say that grains, tubers and salt are great evils and that lean meats should be eaten in abundance.

There's always some report about how some food is either a "superfood" or should be always avoided. I am vegan so I don't eat meat or other animal products and I try to stick to foods which are not highly processed (rice or noodles and vegetables or beans are common staples for me) and I try to stick to organic wherever possible.

I know I didn't eat tofu, miso, tempeh, edamame, etc. for about 8 years because of the anti-soy fears but if soy was really bad for you wouldn't there be records of the problems in Asian countries which routinely consume soy? I'm always dubious about prescriptive diets which claim to have found the "perfect" way of eating, whether scientifically or philosophically. Human beings can survive on entirely plant-based diets or entirely animal-based diets, we're a very flexible species. Certainly, junk food is junk and should be avoided and not regarded as food and people should learn how to cook and make time to do so instead of eating microwave dinners, fast food, instant ramen, soda pop and candy bars. Eat real food and get some exercise once in a while and I think most people will be okay, whether they choose to eat meat or not or if they eat soybeans or potatoes or onions. Some people overthink food.