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Spilling The Beans — The Dish on Soy

(By Mary Vance — Reprint with author's permission.)

As someone conscious of her health, I spent 13 years cultivating a vegetarian diet. I took time to plan and balance meals that included products such as soymilk, soy yogurt, tofu, and Chick'n patties. I pored over labels looking for words I couldn't pronounce. Occasionally an ingredient or two would pop up among my fake sausages. Soy protein isolate? Great! They've isolated the protein from the soybean to make it more concentrated in my veggie dogs. Hydrolyzed soy protein? I never successfully rationalized that one, but I wasn't too worried. After all, in 1999, the FDA approved labeling found on nearly every soy product I purchased: "Diets low in saturated fat and cholesterol that include 25 grams of soy protein a day may reduce the risk of heart disease." Soy ingredients are not only safe — they're beneficial.

After several years of consuming various forms of soy nearly every day, something wasn't right. I felt reasonably fit, but somewhere along the line I'd stopped menstruating. I couldn't figure out why my stomach became so upset after eating edamame or why I was often moody and bloated. It didn't occur to me at the time to blame soy, heart-protector and miracle food.

When I began studying holistic health and nutrition, I kept running across risks associated with eating soy. Endocrine disruption? Check. Digestive problems? Check. I researched soy's deleterious effects on thyroid, fertility, hormones, sex drive, digestion, and even its potential to contribute to certain cancers. For every study that proved there was a connection between soy and reduced disease risk, others cropped up to challenge these claims. What was going on?

"Studies showing the dark side of soy date back 100 years," says Kaayla Daniel, PhD, clinical nutritionist and author of The Whole Soy Story: The Dark Side of America's Favorite Health Food. "The 1999 FDA-approved health claim pleased big business, despite massive evidence showing risks associated with soy, and against the protests of the FDA's own top scientists. Soy is a global four-billion-dollar industry that's taken these health claims to the bank." Besides heart health, the industry says that soy consumption can alleviate symptoms associated with menopause, reduce the risk of certain cancers, and lower levels of LDL, the "bad" cholesterol.

Epidemiological studies have shown that Asians, particularly in Japan and China, have a much lower incidence of breast and prostate cancer than in the US, and many of these studies trace the results back to a traditional diet that includes soy. Daniel says a common misconception is that Asians are consuming more soy than they actually are; soy accounts for only about 15 percent of their total calories, or nine grams per day. Asian diets include small amounts of primarily fermented soy products, such as miso, natto, and tempeh, and some tofu. By contrast, in the US, processed soy food snacks or shakes can contain over 20 grams of soy protein in one serving.

"There is important information on the cancer protective values of soy," says Ed Bauman, PhD, clinical nutritionist, head of the Bauman Clinic in Sebastopol and director of Bauman College of Holistic Nutrition, who cautions against painting the bean with a broad brush. "As with any food, it can have benefits in one system and detriments in another. If there is an individual sensitivity, one may have an adverse response to soy. And not all soy is alike," he adds, referring to processing methods and quality.

Soy is indigenous to Eastern Asia, where it was once considered toxic and used only as a cover crop. It was eventually fermented for better digestibility; it had long been known that soy caused extreme digestive distress if consumed raw or undercooked. Fermenting soy deactivates these harmful constituents and creates health-promoting probiotics, the good bacteria our bodies need to maintain digestive and overall wellness. Daniels mentions that Asian populations may have had success with soy because they are consuming primarily the fermented forms.

As soy moved west, it became a new addition to the diets of Europeans and Americans. "Soy is not a native food to North America or Europe, and I think you have issues when you move food from one part of the world to another," Bauman says. "We fare better when we eat according to our ethnicity. I think soy is a viable food, but we need to look at how it's used and maybe consider using other food stock that's more indigenous."

Formerly considered a small-scale poverty food, soy exploded onto the American market. Studies — funded mostly by the industry — began singing the praises of soy's ability to lower disease risk while absolving one from guilt associated with meat consumption. "The soy industry has come a long way from where some hippies would start boiling up the beans," says Daniel. "It's very much about the marketing."

Marketing includes spotlighting philanthropic efforts. The soy industry would like us to believe that it can alleviate the world's hunger problem by introducing soy to third world countries. "Rather than encourage people to grow a variety of indigenous things, the industry goes in and basically replaces wheat, lentils, vegetables and chickens and goats with soybean plants," Daniel says. Most often those plants are genetically modified to withstand spraying with herbicides such as Roundup and Partner. The aim is to reduce competition by weeds and grasses, a boon for agribusiness.

Large farm or small, the environmental effects of introducing a non-indigenous crop can be detrimental. "In Argentina and Brazil, most of the big farms are eating up the rainforest for GM soy, and they're using massive amounts of pesticide," Daniel says. "People in the surrounding areas are developing all sorts of health problems. They're busy exporting the soy to places like China rather than focusing on growing their own food."

By now, the industry has discovered ways to use every part of the bean for profit. Soy oil has become the base for most vegetable oils; soy lecithin, the waste product left over after the soybean is processed, is used as an emulsifier; soy flour appears in baked and packaged goods; different forms of processed soy protein are added to everything from animal feed to muscle-building protein powders. "Soy protein isolate was invented for use in cardboard," says Daniel. "It was approved for packaging but it was never given GRAS [generally regarded as safe] status. It hasn't actually been approved as a food ingredient."

Soy is everywhere in our food supply, as the star in cereals and health-promoting foods or hidden discreetly in processed foods. Even if you read every label and avoid cardboard boxes, you'll likely find nd soy in your supplements and vitamins (look out for vitamin E derived from soy oil), in foods such as canned tuna, soups, sauces, breads, meat (injected under poultry skin), and chocolate, and in pet food and body care products. It may hide in your tofu dogs under such aliases as textured vegetable protein (TVP), hydrolyzed vegetable protein, or just plain lecithin.

Extensive processing to hydrolyze soy protein into vegetable protein produces excitotoxins such as glutamate (think MSG) and aspartate (a component of aspartame) as byproducts. Food-borne excitotoxins are ubiquitous in processed foods and cause brain cell death.

Soy is one of the most allergenic foods, in addition to wheat, corn, eggs, milk, nuts, and shellfish. Most people equate food allergies with anaphylaxis, or a severe emergency immune response, but it is possible to have a subclinical sensitivity to a food. These lead to health problems over time and are exacerbated by a lack of variety so common in today's American diet.

"People can do an empirical food sensitivity test by eliminating the food for a period of time and reintroducing it to see if there's an immune response, but most don't do this," says Bauman. "Genetically modified soy is the most problematic, and that's probably what most people are eating if they're not paying attention. People can develop a sensitivity to a food that has antigens or bacteria not originally in the food chain, as is the case with GM foods."

Agri-giant Monsanto obtained FDA approval to market GM soy in 1996, and by 2004, a staggering 85 percent of the US crop was genetically modified. Daniel says, "One question I get all the time is, 'What if I only eat organic soy?' Their assumption is that GM soy is problematic and organic is fine. Certainly, organic is better, but the bottom line is that soybeans naturally contain plant estrogens, toxins and anti-nutrients, and you can't remove those."

Anti-nutrients block enzymes needed for digestion. Soy's naturally occurring phytates block absorption of essential minerals such as zinc. This is most worrisome for vegans and vegetarians consuming soy as their main source of protein, and for women in menopause who may be further upping their soy intake through supplements.

The highest risk population is infants. "The reason," says Daniel, "is because it's the only thing they're eating, they're a very small size, and they're at a key stage developmentally. The estrogens in soy will affect the hormonal development of these children, and it will certainly affect their growing brains, reproductive systems, and thyroids." Soy formula also contains large amounts of manganese, which has been linked to ADD and neurotoxicity in infants. Such effects prompted an investigation by the Israeli Health Ministry that resulted in an advisory stating that infants should avoid soy formula altogether.

Soy contains phytochemicals — plant nutrients with disease-fighting activity — called isoflavones, which act as plant estrogens (phytoestrogens) in humans. Studies claim that isoflavones can mimic the body's own estrogens, raising a woman's estrogen levels, which fall after menopause, causing hot flashes and other symptoms. On the other hand, the phytoestrogenic effects of isoflavones may also block the body's estrogens, which can help reduce a woman's high estrogen levels, therefore reducing her risk for breast or uterine cancer before menopause. High estrogen levels have been linked to cancers of the reproductive system in women.

Isoflavones are thought to be useful in warding off cancer due to their antioxidant effect, neutralizing cancer-causing free radicals in the body. Although soy's isoflavones may have an adaptogenic effect — contributing to an estrogen-boosting or -blocking effect where needed — they may also have the potential to promote hormone-sensitive cancers in some people. Studies on isoflavones' effects on human estrogen levels are conflicting and it is possible that they affect people differently. In men, soy has been shown to lower testosterone levels and sex drive, according to Daniel.

Bauman believes processed soy foods are problematic but maintains that soy has beneficial hormone-mediating effects. "People are largely convenience- driven. We're looking at this whole processed food convenience market and we're making generalizations about a plant. Is soy the problem, or is it the handling and packaging and processing of the plant that's the problem?"

"Primary sources of food are a good thing," Bauman states. "Once there was a bean, but then it got cooked and squeezed and the pulp was separated out, and it's heated and processed for better shelf-life and mouth feel. Soymilk is second or third level in terms of processing."

Bauman's eating-for-health approach entails ingesting a variety of natural and seasonal unprocessed whole foods, including soy in moderation, tailored to one's biochemical individuality and sensitivities. "Using soy as a part of a diet can bring relief for perimenopause, for example," he says. "Throw out the soy and you throw out the isoflavones." (It is possible to obtain phtyoestrogens to a lesser extent from other foods, such as lima beans or flax.) "The literature is extensive on the benefit of soy, and that should always be stated, just as the hazards should be. That's science. These studies are not ridiculous or contrived, but take a look at them. Who's funding them?" asks Bauman.

"There are a lot of problems with these studies," Daniel says, adding that the 1999 heart health claim was an industry-funded initiative. "My position is that even if there is positive information, and even if these studies are well designed, we need to weigh that against the fact that we've also got really good studies showing the dangers. The precautionary principle states better safe than sorry. Possible benefits are far outweighed by proven risks."

Dietary needs are different for everyone and change according to the body's needs. Daniel and Bauman both agree on the benefits of variety. "As a clinical nutritionist, my experience is that people who have a varied diet tend to not get into trouble," says Daniel.

"We like to demonize certain foods in this society," says Bauman. "If you want to find fault, you'll find it. The bottom line is, what is a healthy diet?"

Q & A

Mary Vance: What health problems do you see in your practice that can be traced back to over-consumption of soy?

Kaayla Daniel: I work mostly with mid-life women, and that is a population likely to eat a lot of soy and drink a lot of soymilk. They're even taking soy isoflavone supplements because they've heard that it's going to help them through menopause. A lot of these women are very intelligent and educated, and unfortunately they get this idea that if a little of something might be good, then they should do a lot of it. They start doing a whole lot of soy, and they start gaining weight, feeling fatigued, they get lethargic and depressed, and when they go to a regular doctor, they're told, "Well, what do you expect, you're getting old," and that this is typical of menopause. In fact, the symptoms are almost entirely coming from that change in their diet, which had to do with soy.

How much soy does the average person consume in a day?

Someone on a junk food diet is getting soy flour in their fast-food burger bun, soy protein in the burger itself, and soy oil in the fries; soy is in every one of these products because it's cheap and abundant. You'll find soy hidden in so many foods, and these small quantities add up.

People often start by drinking a lot of soymilk. If they are doing supplements, they can be getting really high doses and that's where it starts to get very scary. Even scientists working for the soy industry will say they support soy food but do not support use of soy supplements, so I think that's something just about everyone has agreed upon. It is so dangerous at such a high level, and it's harming many people. Women say [drinking soymilk] makes them feel good. Most soymilks have a lot of sugar, so they might be getting a sugar hit. The other thing that may happen is with the thyroid. Short-term, soy may stimulate the thyroid so they'll feel better, but the thyroid gets stressed out from extra stimulation and goes long-term into hypothyroidism.

How does marketing affect soy consumption?

It's very much about marketing. If we look back, the soybean was used in this country for soy oil. They take apart the bean and take out the oil and turn it in into margarines and shortenings and all those liquid vegetable oils. Once the oil is out, what they had left over was a whole lot of protein.

The USDA has spent so much money and many decades researching how to use soy in animal feed so that the animals will stay healthy. Some of the problems they were running into were that the animals were having birth defects; they were having fertility problems; they were dying prematurely on soy feed. The USDA was looking into what vitamins, minerals, or amino acids they needed to add and what is the maximum amount of soy they can use in animal feed before the animals have too many problems. They don't care that the animals would have thyroid problems and get fat because that's their objective anyway. Soy is not a natural food for an animal. Only so much soy can be used in animal feeds before there's big problems. For instance, with poultry feed, it's 25 percent.

How should people interpret the conflicting information on studies about soy and cancer?

The soy industry has really been running with the recent study where they asked people what they'd been eating during childhood and teenage years; women with the highest soy intake were the ones with the lowest rates of breast cancer. There are a lot of problems with that kind of study. First, if I started to interview you right about what you ate last Tuesday, could you tell me and tell me how much? When people are talking to an interviewer, they like to say what the interviewer wants to hear; there's a potential for bias. In the latest study, it was only like two servings per week and in all probability it was not things like soy energy bars or shake powders. It was miso soup or tofu. Maybe they were a traditional family eating a lot of foods from scratch. There are other foods and other factors you could get these benefits from.

Is increased soy consumption a reason that girls are hitting puberty as early as eight or nine?

There's a good reason to think that soy formula is part of that problem, but we also have environmental estrogens and pesticides and plastics and supermarket meats, xenoestrogens. Soy may be the one thing we can completely avoid.

What provoked the Israeli Health Ministry warning on soy foods?

The Israeli Health Ministry issued an advisory that babies should not get soy formula, and that children to age 18 should eat soy no more than once per day, three times per week maximum. Adults should exercise caution due to the adverse effects on fertility and increased breast cancer risk. It's a pretty strong statement and a good start.

Were they seeing problems or was it a precautionary measure?

Both. It started a few years ago when several babies were hospitalized with severe beriberi and brain damage because of a soy infant formula that was deficient in vitamin B1. The manufacturer had gotten the idea that why should they add extra B vitamins if soy is such a perfect food, already high in B vitamins? They didn't understand that babies need added B1 and that processing affects vitamins. National alerts were issued, the product recalled, and all the babies on soy formula immediately got injections of B1.

That incident caused the Israeli Health Ministry to start looking into soy formula. They formed a large committee including toxicologists, oncologists, pediatricians, and other experts, reviewed the literature, and decided that there are some risks. The Israeli soy industry has protested mightily and threatened to sue the government, but the health ministry maintained its position.

Daycare centers have been told to cut back on soy foods. They were [serving soy products] every day and now they're doing it three times a week. I would say that's still a little too much for children, but it's a big start.

How much soy should people consume, if at all?

I'll use the numbers the Israelis used. But of course some people are allergic to soy; some are sensitive to soy; some have thyroid problems already. Those people probably should avoid it. Then there's the issue of what types of soy are we talking about. I still enjoy miso soup.

Which soy product is the worst?

The biggest problem is soymilk. Those with lactose intolerance are thinking that soymilk is a great alternative, and they're drinking a lot and getting a huge dose of isoflavones. If you're drinking soymilk, you're going to have a problem, or most people will sooner or later. We're all different — some people will start having problems in a day, and some people will think they're fine and a year later things will start to go downhill.

Drinking just one glass a day of soymilk will give someone the level of plant estrogens that has hurt the thyroids of healthy Japanese men and women. Most people are doing several glasses, plus the soy protein energy bars and the bags of edamame.

If people are worried about calcium, they could try coconut milk, which has the calcium, magnesium, and potassium they'll get from cow's milk and is a wonderful tonic. I don't recommend rice milk due to the sugar content. It's still a heavily processed food. Many lactose-intolerant people find they can tolerate raw milk that hasn't been pasteurized, which kills the enzymes needed for digestion.

Before they started using soy protein isolate they used soy flour, and that gave babies very bad gas. Once they started using soy protein isolate they were having fewer problems in terms of gas and overall digestability. Babies in the short term seemed to be doing better. The problems with hydrolyzed plant protein include that the processing creates MSG and other excitotoxins, and we get that with soy protein isolate as well.

Also, the protein is unstable when soybeans are cooked a long time. It's a very tricky thing to not cook them too long or to cook them long enough — it varies from bean to bean. Some of the USDA studies were going on for years: how to do that processing to make it work. Then they finally gave up. What's happened is some of the things they tried to get rid of they're now marketing as things that can prevent cancer or prevent problems. They take something that's bad and turn it into something that's good. Every time they remove a component of soy, they have another thing they can sell.

In Kenya, the soy industry is talking to bakers, teaching them to use soy flour in baked goods, and down in Johannesburg they're working on using soy protein shake powders to help AIDS patients. When the tsunami hit, the soy industry was right there giving people assistance and free soy products. Rather than help the people pick up the pieces and get their small farms back together, they're replacing the local foods with something that's global.

WhiteWave Foods, which makes Silk Soymilk, started out as a small company in Boulder, but it is now owned by Dean Foods. You see it in supermarkets everywhere. And Dean Foods — you don't have to look very far to see what kind of products they're selling. Kellogg and Dean and Con-Agra — all these big companies own what used to be small-time companies. New standards for organics means quality assurance goes down. We need to be looking at buying locally. Transportation alone has a very serious toll on the environment.

Do you think we should have a warning label here in the US?

That's the next step to take. I will be involved with three petitions to the FDA. The first will be to remove the current health claim that soy prevents heart disease. It's been on foods since November 1999, and in fact, soy food sales went from less than a billion to $4 billion between 1999 and 2004. They had planned to get a "soy prevents cancer" claim but we put a stop to that. Last year, the American Heart Association retracted its position on soy. They're now saying soy does not prevent heart disease or lower cholesterol. Secondly we're going to petition the FDA to remove the GRAS status for soy protein isolate. The third will have to do with putting warning labels on soy foods.

Do you think that labeling will be a reality in the US?

We're hopeful our petitions work but the other part is that we're bringing attention to the issues. What amazes me is that so many vegetarians and vegans will say that the FDA would never have approved a "soy prevents heart disease" claim unless there was good strong evidence. Hello! This is the same FDA that gave us Vioxx and aspartame!

I'm sure in Berkeley in the '60s there were little companies that made tofu and soymilk, and people still believe soy is that kind of food. What they're not getting is that we have Big Pharma and now we have Big Soy. It is a global industry. The industry is whining because growth has slowed. They're hoping for the next big product. They had high hopes that soy protein sales would go from four to eight billion by 2007 with the "soy prevents cancer" health claim, but we killed that for them.

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