ORDER NOW
Let’s be real: soy is kind of a controversial food. Once it was considered to be the ultimate health food, and then suddenly it became the worst substance you could be eating. What gives? What do we actually know about soy, and is it a right fit for you? With all food, context matters, and it’s usually not a simple case of bad or good. So let’s dive in.
Soybeans are a type of legume, and they’ve been a staple of traditional Asian diets for thousands of years. They can be whole, or they can be processed (and you can bet that has an effect on their health properties). Some soy foods include:
The biggest controversy when it comes to soy is its potential risk in impairing thyroid function and causing cancer (particularly breast cancer). This is because soy contains isoflavones, which are compounds that mimic estrogen.
Early research on these compounds found that they could promote the growth of cancer cells, cause infertility and negatively impact thyroid function. (1, 2, 3)
But again, context is key: most of the research that found these links looked at isolated soy compounds, removed from its whole food source. The problem with this is that we don’t typically eat soy like that, and whole foods behave differently in the body in comparison to isolated compounds because they work synergistically with other nutrients and fibre.
Another thing to note is that these studies looked at the effects of soy either in animals or in vitro (test tubes), and typically in larger quantities than we’d ever eat in a day. While this might give us some insight, it doesn’t account for the fact that soy may act differently in the human body or that some animals aren’t designed to tolerate soy.
In fact, research in humans found that soy could actually help fertility. (4) Recent research shows that soy products can also help to reduce the risk of breast cancer unless you’re a carrier for the BRCA2 mutation gene, in which case you might want to limit or avoid soy. (5)
Another common reason to avoid soy is because it contains antinutrients like phytates, agglutinins and trypsin inhibitors. Animal research done on agglutinins in soy found that it could increase intestinal permeability and disrupt healthy gut bacteria. (6,7)
However, like other foods that contain antinutrients, cooking, fermenting and sprouting soy helps to decrease the levels of antinutrients and also increase digestibility. (8) Again, how soy affects you will largely depend on the state of your own gut health.
In general there are lots of health benefits to soy (which we’ll dive into below), but the type of soy makes all the difference.
Opt For Minimally-Processed or Fermented. When it comes to soy products, fermented or minimally-processed soy is best. Foods like tempeh, miso, tofu and edamame offer up fibre, protein and nutrients like magnesium, iron and calcium. (9)
Choose Organic and Non-GMO. Another problem with soy is that it usually comes from genetically modified crops, which tend to be heavily sprayed with the herbicide glyphosate, which may negatively affect the endocrine system.
Avoid Heavily Processed Soy. When it comes to processed soy like textured soy protein, soy protein isolate (found in protein bars) or soy lecithin, it’s better just to avoid it. These products tend to offer up little nutritional value and often come with the baggage of additives and fillers.
One of the best ways to consume soy is in the form of tempeh, as it’s a fermented, whole-food source of tempeh.
If you’re looking for a source of plant-based protein, soy in its whole food form might be a healthy option for you in moderation. You may want to limit soy if you have an underlying health condition (like hypothyroidism), but if you’re in good health, 3-5 servings of soy a week is perfectly healthy!
Ready to give it a try? Impact Kitchen is super excited to launch our new organic, non-GMO marinated tempeh, available at all locations. We’ve had so many requests over the years for another plant-based option, and we didn’t want you to go unheard!
We’ve also been interested in the effect of a plant-based diet on longevity and have been looking to places—like the Blue Zones of Italy, Greece and Japan—to see what they’re doing. And as it turns out, these populations are eating a primarily plant-based diet with the inclusion of soy and legumes. (14,15) You’ll notice we’ve even added some new bowls to our menu (the Victory and the Thrive bowls!) that include legumes and lots of plants for this very reason!
Let us know: what are your thoughts on soy? Have your views shifted over the views with new research?