There are a lot of mixed messages about soy out there right now. It’s hard to know if you should eat it or not. If you do eat it, how much is okay and how often should you eat it?
The American Dietetic Association confirms that soy is a great source of protein (it has as much protein as meat), B & D vitamins, fiber, minerals, and essential fatty acids. Soy is a good way to get these benefits without the cholesterol and saturated fat contained in meat. The FDA also agrees that soy can help fight heart disease and strengthen bones. However, it is also highly processed and nearly all soy sold in the USA is genetically modified (GM) unless it’s organic. What’s wrong with GM food? Many would argue there’s no difference in GM food and non-GM food, but studies are popping up that suggest otherwise. This is another day’s blog all together, but I want to provide a few links about it. Here are a couple of links where you can read about how GM soy has been linked to sterility, infant mortality in lab animals, malformations in amphibian embryos, and altered gene expression in rats:
The bottom line, from what I gather from many different sources, is that it is scientifically unjustifiable to say that GM soy is safe for human consumption.
The GM issues aside, let’s say you’re eating organic soy products. Is that okay? Well it depends on who you are and how your body reacts to soy. Soy contains goitrogens that can interfere with thyroid function, causing it to become enlarged. There are many people “out there” (on blogs and message boards and such) who say soy ruined their thyroid and they now have to take medication. Soy also contains phytoestrogens (plant estrogens, basically) and there are mixed messages out there about whether phytoestrogens can be linked to breast cancer or whether, in moderation, they can help prevent breast cancer. Phytoestrogens tend mimic your own estrogen in the body, but they can also have very different effects. I read a Vegetarian Times article once that explained it like this:
Imagine that your blood stream is like a runway at an airport. Your own estrogens are like jumbo jets. Phytoestrogens come in and they are like smaller planes, all gathering together and blocking the jumbo jets from entering the runway. This messes the flow of everything up. Some studies say that keeping the jumbo jets out of the way reduces your risk of cancer. But I’ve also read that keeping them zooming around in your bloodstream may increase the risk. Some sources mention that Japanese women have been eating soy for centuries and their cancer risk has been significantly lower as compared to those who eat the standard American diet. But when it comes to saying people have been doing “X” for years and they’ve been OK, I have to remind myself that things are changing drastically. Centuries ago, women in Japan didn’t eat GM soy, and soy wasn’t in EVERYTHING like it is now, so they were probably eating it in moderation. There is more information on soy as it relates to cancer here.
As I mentioned before, soy is highly processed and I would by no means consider it a “health food.” Too much processed anything isn’t good for you, whether it’s vegan or not. Soy protein isolate is popping up in everything, as is soy lecithin. There’s soy in canned beans, most brands of peanut butter and mayonnaise, some canned vegetables, and even cake sprinkles! According to the ADA, “soy protein isolate contains antinutrients that can actually delay your body’s ability to digest food and absorb nutrients into the blood stream.” I recently read at LiveStrong.com that processing soy “involves acid washing it in aluminum tanks. As a result, large amounts of aluminum are placed into the finished product. In addition, nitrites and chemical flavorings are used to add flavor. These chemicals have been linked to the development of certain cancers, allergies and even Alzheimer’s disease.” Bad news bears, people!
My opinion? Moderation for most things. I won’t say “everything in moderation” because I believe there are plenty of things that we should try never to eat if we can help it. But if you are eating a healthy, balanced diet that incorporates a variety of whole grains, fruits, beans, and vegetables while limiting your intake of foods with higher levels of pesticides, and one day you want to have a little organic soy, go ahead! Just don’t go overboard. Don’t have soy milk with your cereal in the morning, tofu and soy sauce with your stir fry at lunch, and then veg chicken nuggets for dinner. I would even go as far to say that you should limit your soy intake to less than twice a week. But that’s just me. We were meant to eat foods in their whole form, as they grow from the Earth.