Network News

X My Profile
View More Activity
Column Archive |  On Twitter: J Huget and MisFits  |  Fitness & Nutrition News  |  RSS Feeds RSS Feed

Is Soy Safe -- or Scary?

A study I reported on briefly in yesterday's health section suggests a possible link between men's soy intake and reduced sperm concentration. The Soyfoods Association of North America quickly issued a statement debunking that study.

This isn't the first time soy's risk/benefit ratio has been called into question. In fact, the health effects of soy-based foods and dietary supplements are poorly understood and hotly debated.

Interest in soy as a health-promoting food stems from the observation that populations that have historically consumed a lot of soy -- particularly Asians who eat lots of tofu, miso, and tempeh -- have typically enjoyed good health and have lower incidence of such diseases as breast cancer. But nobody knows for sure whether those good outcomes are directly related to eating soy or to some other aspect of these people's lives and behaviors.

Soy and the isoflavones it contains have been touted for their cancer-fighting capacity and cardiovascular benefits. Isoflavones are thought to behave in the body in much the way that estrogen does, but scientists haven't quite figured out whether they work for good or for ill -- or both.

According to Connie Weaver, head of the department of foods and nutrition at Purdue University, flaws have recently been recognized in the research methodology on which our current understanding of soy's pros and cons are based. Much of that research has been in animals, she says, and apparently nobody thought to take into account the compounds -- potentially including those that have estrogenic effects -- that may have been in the chow those animals were fed. "A lot of what we thought we knew is confounded," Weaver says. "And we can't go back and unravel it because nobody was keeping track" of what the animal subjects were fed.

On top of that, she says, soy research is inherently complicated: There are so many varieties of soy, soy-based products and soy derivatives, any of which might have different effects depending on who consumes them and at what stage of their life they do the consuming. It's possible, for instance, that a person who has eaten soy all her life may enjoy protection against breast cancer, while a woman who already has an estrogen-sensitive tumor when she starts eating soy will find her cancer is exacerbated, Weaver explains.

None of this is news to the National Institutes of Health (NIH); that agency plans a workshop next April to address human soy studies and to grapple with issues raised in this 2005 report. In the meantime, the Web site for NIH's Center for Complementary and Alternative Medicine (NCCAM) says the agency has included basic and clinical research into soy protein and soy isolates among the areas of research from which it's taking a brief "pause."

For what it's worth, here's the federal government's most up-to-date assessment on soy. In short, based on the best available evidence, science strongly suggests that soy is a good source of protein and that it may lower overall cholesterol and low-density lipoproteins (LDL, or "bad" cholesterol) moderately. But it's not been shown that that translates into fewer heart attacks or strokes.

Science is more wishy-washy, but generally supportive, when addressing the idea that soy may help ward off diarrhea in infants and young children and ease some symptoms of menopause (such as hot flashes).

For all the other health benefits -- including those related to cancer and cardiovascular health -- attributed to soy intake, the government-funded analysis (issued in March by the independent Natural Standard Research Collaboration) finds inconclusive or contradictory evidence.

So what's your stance on soy? Do you eat soy-based foods because you like them? Or because they're supposed to be good for you? Do you feel your health's better because you eat soy? Or do you worry about soy's possible risks?

By Jennifer LaRue Huget  |  July 30, 2008; 7:00 AM ET
Categories:  Alternative and Complementary Medicine  
Save & Share:  Send E-mail   Facebook   Twitter   Digg   Yahoo Buzz   Del.icio.us   StumbleUpon   Technorati   Google Buzz   Previous: Keeping Weight Off Takes More Exercise Than You Think
Next: Worriers Rejoice!

Comments

I eat them because I like them and I appreciate the fact that it is low calorie, vegetarian, and high protein, which is a difficult combination to find.

Posted by: anon | July 30, 2008 8:15 AM | Report abuse

I think the key here, as with everything, is moderation. Too much of a good thing isn't always such a good thing. I didn't get the proper amount of calcium growing up because I'm slightly lactose intolerant. As a kid, soy milk was not a widely available option, especially since my parents had a limited income at that time. However, a year ago, at 17,I started to drink soy milk as an alternative to milk. I feel better, but I don't know if it's because I started getting more calcium. I've also noticed that my skin is a lot healthier. I've always loved soy beans, and I started eating tofu because I have a number of vegetarian friends who eat tofu to get their protein (tofu tacos are REALLY good.) As to the risks--well, there are always risks, some are just less riskier than others. For now, I'll stick to moderation because I think my risk for getting osteoporosis from lack of calcium is greater than the risks that soy poses.

Posted by: Anonymous | July 30, 2008 8:23 AM | Report abuse

We have never approached this issue scientifically, but my wife and I (76 and 75) have eaten a soy product almost every day for the past half century and are convinced that soy is a gift of the gods.

For one thing, soy's high protein content removes the need for eating meat, and is much more efficient to produce in terms of energy and other resource consumption. It can be prepared in a variety of ways that are appealing to the palate, and when combined with a grain such as barley, wheat or rice, provides a complete protein that is the equivalent of meat.

Besides, the animals that we would otherwise consume have shared the aeons of the same evolutionary process that created us humans. They are our kith and kin, and deserve our respect rather than serving as mere dietary constituents.

Posted by: David | July 30, 2008 9:01 AM | Report abuse

I stopped my wife from drinking soy milk because I am surrounded by fields and no deer or birds eat it. Breast cancer here in Pa. is door to door and I guess it all depends on the farmer who sprays cancer chemicals on our fruit and vegetables. Here I wouldnt eat a deer or rabbit because that all he does on a daily basis is spray spray and spray. This is why smoking is cancerous because the more the tobacco is sprayed the better the quality and its more money for the farmer in which the better quality tobacco the qicker the smoker dies. You see the commercials on tv telling you to eat fruits and vegetables but you dont know how many times the farmer sprayed and the wax on most covers the chemicals in which you cannot wash it off. There areno birds, rabbits or nothing here but Chemotherapy in which my home will be torn down and notr passed on to my children for cancer. High nitrates in the wells here since 1997 shows what kind of farm family is here and my letters for over ten years have gotten nowhere. Soy leave it alone.

Posted by: Dennis | July 30, 2008 9:45 AM | Report abuse

I have thyroid problems and soy is a definite no-no in excess. One serving a day is about the limit recommended.

Posted by: Emily | July 30, 2008 9:45 AM | Report abuse

Soy products that mimic meat products are pretty scary. I know too many folks who eat them thinking that they are getting something healthier than meat, without looking at the ingredients. These products are generally laden with sugar, artificial flavors, and preservatives to make them appealing. They are so processed that those benefits of soy are non-existent.

With that said, I love tofu. I also realize that, like my meat intake, I must eat this in moderation. Soy milk doesn't have the benefits that cow and goat milk does. The calcium in these in soy product is artificial, and not absorbed by the body. My suggestion to those who are lactose intolerant is to drink grass-fed whole cow's milk. I too had trouble drinking skim milk, because our body needs the fat to digest it. As result, I've lost weight in gaining a convenient and suitable protein source.

Posted by: Mz Fitz | July 30, 2008 10:11 AM | Report abuse

We've eaten soy in one form or another every day for probably 20 years. Don't know where we'd be without it.

Posted by: SaraBeth | July 30, 2008 10:14 AM | Report abuse

I've been on both sides of the soy debate over the past several years. At one point I was making my own soy milk. But I stopped when I became aware of the downside of soy, and began to be alarmed at its pervasive use in so much of what we eat.

There is no question that soy has certain benefits, but there are some very convincing detriments as well. Each side trots out its narrowly-focused studies to prove its point.

It's been noted that no society in history has consumed soy to the degree we have, not even in Asia. And in Asia much of the soy consumed is first fermented.

Until we have better perspective, my policy is moderation. I think a small amount of soy will be beneficial and that its dowside could probably be handled by the body. Some soy is most probably unavoidable anyway, so this way I don't have to worry about it, which in itself is not good for health.

Posted by: Paul B. | July 30, 2008 10:59 AM | Report abuse

I've been on both sides of the soy debate over the past several years. At one point I was making my own soy milk. But I stopped when I became aware of the downside of soy, and began to be alarmed at its pervasive use in so much of what we eat.

There is no question that soy has certain benefits, but there are some very convincing detriments as well. Each side trots out its narrowly-focused studies to prove its point.

It's been noted that no society in history has consumed soy to the degree we have, not even in Asia. And in Asia much of the soy consumed is first fermented, which removes many of the detriments.

Until we have better perspective, my policy is moderation. I think a small amount of soy will be beneficial and that its dowside could probably be handled by the body. Some soy is most probably unavoidable anyway, so this way I don't have to worry about it, which in itself is not good for health.

Posted by: Paul B. | July 30, 2008 11:00 AM | Report abuse

These products are generally laden with sugar, artificial flavors, and preservatives to make them appealing.
----

In other words, these soy products are no different than what's done to meat in grocery stores these days (read those labels!)

Posted by: Anonymous | July 30, 2008 11:49 AM | Report abuse

To Anon:
Absolutely! Plant based diets with a range of protein sources are probably the safest way to go, no matter what study comes out next week.

ALWAYS read labels.

Posted by: Mz Fitz | July 30, 2008 12:02 PM | Report abuse

A family friend is deathly allergic to soy (which makes cooking for her a challenge, as she can't even eat products that might have been processed in the same plants as soy, such as any oils other than cold-pressed olive oil) and she developed it in her 20s - perhaps from an overexposure the the various soy additives in processed foods?

In general, I believe whole foods are safest. Folks who avoid "processed food" happily chow down on tofu - I don't get it.

Edamame and soy nuts - love 'em. Soy sauce is a guilty pleasure. But we stay away from the meat substitutes and various convenience foods that have soy protein added - eat some beans and rice instead

Posted by: DrMary | July 30, 2008 12:18 PM | Report abuse

Vegetarians like me definitely eat soy for the protein content. I eat soy yogurt because I am lactose intolerant. Do I eat a truckload of tofu at a time? No! Just like most meat eaters don't eat the whole cow. As others said, if you eat in moderation and not to excess, you are generally OK.

Posted by: DB | July 30, 2008 12:23 PM | Report abuse

You said "populations that have historically consumed a lot of soy -- particularly Asians who eat lots of tofu, miso, and tempeh -- have typically enjoyed good health"
In China and Japan they eat about 2T of soy a day. Americans eat much more than that because some sort of soy is normally in processed foods. I do not know why this perception of soy consumption in Asia is continued,especially because actually consumption has been studied many times.

Posted by: Anonymous | July 30, 2008 12:47 PM | Report abuse

Regarding the comment about cancer-causing chemicals on fruits and vegetables: That's one of the many reasons to buy organic or local if you can. Don't make it stop you eating fruits and veggies!

As for the combining proteins comment, that's now considered a fallacy. Grains and beans definitely taste good together, but you don't have to eat them at the same meal to get the amino acids your body needs.

I eat soy regularly (soymilk, tofu, Boca burgers, edamame, soy protein smoothies) because I like it and it's a high-quality vegetarian protein. However, I would prefer if the U.S. did less genetic modification of foods and depended less on industrial monoculture farming that creates harmful nutrient runoff, pesticide residues in our food and a dearth of habitat for wildlife.

Posted by: Calliope | July 30, 2008 1:09 PM | Report abuse

I was under the impression that soy is a natural source of estrogen...wouldn't that possibly account for lowering men's sperm concentration?

Posted by: Oh Soy | July 30, 2008 1:33 PM | Report abuse

Doesn't soy fail the "Eat only what your grandparents might have eaten" test?

As for tofu, that stuff is just creepy.

What I really object to is foods like canned tuna that contain vegetable broth and a label that notes the presence of soy. Why put soy in tuna?

Posted by: Bartolo | July 30, 2008 1:41 PM | Report abuse

I'm going to reiterate what others have posted a bit. Soy in the quantity that Asians eat it is good. Soy in the quantity that Americans eat it can be bad. It's that highly concentrated processed soy that's the problem. Eat all the edamame you want. Keep the soy milk consumption at a minimum.

Posted by: atb | July 30, 2008 1:48 PM | Report abuse

It's no secret that the very powerful, highly government-subsidized meat and dairy industry is largely to blame for the labelling of soy as "scary".
Who eats all soy every day? If you are eating only one type of food, you are bound to feel negative effects, no matter what. There must be a VARIETY of fruits, grains and vegetables in one's diet to be properly nourished.
And in response to Mz Fitz, animal milk is artificially fortified with calcium as well, and is a higly INEFFICIENT way of getting calcium as the high protein content in milk negates the absorption of calcium and actually leaches calcium from your bones. Why do you think we in the West have a much higher incidence of osteoporosis? If milk is such a perfect conveyor of this nutrient, why is this the case when this country consumes so much of it??
As a vegan, I do consume some soy products, but I don't base my diet on it; it is but just one of the MANY vegetables I eat, so to worry about the so-called "risks" would be ridiculous.

Posted by: vegbikr | July 30, 2008 2:16 PM | Report abuse

I suspect the "anti-soy" arguments are all put forth by the dairy industry which wants americans drinking hormone & antibiotic laced cows' milk rather than soymilk, and the beef industry, which wants americans eating hormone & anitbiotic laced meat rather than soyproducts.

Posted by: michelle | July 30, 2008 2:22 PM | Report abuse

To the soy-yogurt eater: Many people with lactose intolerance can actually eat regular dairy yogurt without a reaction because the natural bacteria present aid in lactose digestion. I'm able to eat low-fat (not non-fat - which has more lactose) yogurt just fine.

http://digestive.niddk.nih.gov/ddiseases/pubs/lactoseintolerance/

Posted by: Soy Yogurt | July 30, 2008 4:17 PM | Report abuse

Actually, the milk that I drink is not artificially fortified. I have done my research, and am sure of that.

To each his own. I ate a mainly veg/vegan diet properly for many years, and found that my health has rebounded tremendously when I began cutting back on soy intake, and increasing the right protein. I am fortunate enough to live in an area where I can easily acquire local meat and dairy. I can visit and speak with the farmers to discuss their methods, and have seem my health steadily improve.

I have an issue with "replacement" products. After having eaten vegan cupcakes last week, I was disturbed to find out that some type of powdered egg substitute and margarine were used. I was under the impression that vegans used apple sauce and other natural foods as a replacement. When I asked why they did this, I received a snarky answer for inquiring. When I feed vegans and vegetarians, I always disclose the ingredients and cook using equipment that has not had meat on it.

Posted by: Mz Fitz | July 30, 2008 4:26 PM | Report abuse

Just venting a little bit of frustration on some of the comments.
First, these studies about soy have been going on for years. This is not the first nor will be the last that shows lowered sperm count with soy. Search google, search Pub Med. Search an article called "the dark side of soy" found on the internet.
Yes, it is the phytoestrogens in soy causing this. The same phytoestrogens promoted when women take soy pills as an estrogen replacer. New Zealand has banned soy in infant formula because of the concerns. Covered in the article I recommend.
There is no such thing as soy "milk". It is soy juice. It amuses me that people have put the two words together and treat them as if they were the same type of food.
I agree that milk has a lot of drawbacks as a food for adults, but that is its own discussion. A great source of calcium is broth, any homemade broth, especially eaten with calcium rich veggies.

Posted by: Anonymous | July 30, 2008 7:46 PM | Report abuse

"My suggestion to those who are lactose intolerant is to drink grass-fed whole cow's milk."

Thanks for the recommendation

Posted by: Anonymous | July 31, 2008 7:37 AM | Report abuse

"There is no such thing as soy "milk". It is soy juice. It amuses me that people have put the two words together and treat them as if they were the same type of food."

I think people call it that because it's generally called soy milk on the carton. I don't think people think they're the same kind of food--no more than people who drink calcium fortifide orange juice believe that it is milk. They treat them as the same type of food in the sense that both are sources of about the same amount of calcium.

Posted by: Anonymous | July 31, 2008 7:45 AM | Report abuse

I disagree with the last post. People do associate soy "juice" with milk. It's not just the label on the carton. Soy is marketed as a dairy substitute and offered in coffee shops as an alternative to milk.

Posted by: Anonymous | July 31, 2008 9:48 AM | Report abuse

I drink Soy daily, because I have Diabetes Type 11 and I have kidney disease. I am lactose intolerant and I love to make fruit shakes using Soy milk.I have to take it easy on protein, but I do not eat much meat at all, so I am safe here.Just give me a Soy Smoothie and I say "Be still my Heart" Love it! Love It!

Posted by: Nina B | August 15, 2008 5:56 PM | Report abuse

The comments to this entry are closed.

 
 
RSS Feed
Subscribe to The Post

© 2010 The Washington Post Company