Has anyone ever run across info suggesting that soy products might actually be harmful?

I’ve heard too much soy can cause increased estrogen levels, but I don’t know how harmful that might be. I knew a guy who had a lot of soy in his diet and he became really emotional, most likely because of all the estrogen in there.

I might be imagining things, but I think we had a discussion similar to this a couple months back. Might want to try doing a quick search to see if anything pops up. :)

Yes. A lot of it depends on how the soy product is produced. Traditional ways of making soy into food (such as tofu, miso, and tempeh) have been eaten safely for a long long time.

I wrote a longer answer for this question here.

I’ve heard that people with thyroid conditions should avoid soy. I’ve never looked into why that is, but I’ve heard it said over and over again.

My oncologist says that the jury is out for tofu and other fermented soy products. Due to the estrogen issues, he suggests strongly that breast cancer survivors (raises hand) eat very little, except for the etamame beans.

It is particularly relative to my type of estrogen-positive breast cancer. I don’t find it hard to substitute something safer to eat.

“Soy products increase the risk of thyroid disease. And this danger is particularly great for infants on soy formula.” Source

According to an NPR review of a book on headaches, when you eat soy, your body is essentially manufacturing MSG, which can trigger headaches for a lot of people.

Soybeans were never widely consumed until recently in history when the “health” market jumped on them. In China, where they’ve admittedly been used for a few thousand years, they’ve primarily been used for soil treatment, not so much for consumption. I think the main problems lie in the hormonal effects they have on our bodies. I know a couple of soymilk babies who spent the better part of their teenage years with male breasts.

@marinelife is right, my mother shut her thyroid down when she went overboard with the soy.

Despite these findings we need to compare the overall benefits and risks with other sources of protein and whether we are talking about small or excessive quantities.

@mattbrowne I’m seeing things like cancer and birth defects from soy-heavy diets.

There are plenty of sources of high-protein that humans have actually been eating during our evolutionary past. Like nuts, seeds, insects, animal flesh, and normal fruits and vegetables believe it or not.

The human body doesn’t need that much protein, really. In fact, too much of it causes problems that most people don’t seem to be aware of like calcium deprivation. We have the technology to make sure everyone gets quality food, we just don’t have the system set up to do it. Too much power relies on our ridiculous power-farming.

So, only the wealthy buy natural foods, and only the hippies grow them. Everyone else gets mostly just the easily processed and preserved (slightly toxic) grains and legumes, and the addictive animal products and drugs when they’re eating really fancy. Because that’s what keeps the money (control) flowing, not just in agriculture, but in all the industries that depend upon the status quo. For example, the medical industry when most people get sick on a regular basis, and the healthfood industry when people desperately seek an alternative.

We’re not supposed to factor in the toxicity of our food as an acceptable variable in diet choices. We’re supposed to demand the healthiest food possible, for everyone, without question. To demand that people work harder for better food is like demanding an engine to run faster for better fuel. Nutrition is the basis of health and health is the basis of life. You can judge a society by their agriculture. And we suck.

@Nullo – What about modest soy diets?

There are a lot of problems with soy. The biggest for us is that most of the soy grown and distributed, particularly in the U.S., is genetically modified and largely not tested (where it is, it looks grizzly). Another is that we didn’t adapt to eat quite as many legumes as many people do in industrialized areas. Sure, some now and again are okay, but not as the central component to our diets.

Another is that the proteins are not that easily digested from legumes, particularly the proteins referred to as lectins. Therefore, the protein contribution of soy products is misleading, because they’re not properly incorporated into our bodies. Some nutritionists refer to them as anti-nutrients because of the way they inhibit the absorbtion of several nutrients. The traditional ways to prepare it, using active culture fermentation, supposedly negate a lot of the problems (and tofu is most definitely not one of the traditional methods). Although the level of Omega 3 fatty acids are often praised, it’s not actually that high and they contain more Omega 6, which is known to increase many inflammations.

Also, while soybeans may have been grown for a long time, they were mostly grown as cover crops to improve nitrogen in the soil and mostly eaten during famines. They have their place, but in very sparing amounts and in certain ways (fermented). It should also be noted that historically the switch from hunting, gathering, and gardening to the adoption of a diet made up mostly of grains and/or legumes marks a dramatic drop in overall health in every account I know of.