Soy is everywhere. It appears in almost any processed food product, in baby formula, as a main dish and a condiment, and even in animal products from animals fed soy (second-hand soy? No thanks!). Some even consider soy a superfood–but is it really that good for you?

The truth is that many people have soy sensitivities or allergies, and even if you don’t, soy can still have a negative impact on your health by creating hormone imbalances. Not so “super” anymore, are you, soy? In fact, hormonal changes are so well-noted in medical literature that they’re hard to miss. Some of the best examples of soy’s negative impact on hormones are delayed menstruation, endocrine disruption to match the degree of the breast cancer drug Tamoxifen, could potentially lead to breast cancer and pose a risk for those who have breast cancer, can suppress the pituitary-thyroid axis, and can drop testosterone levels in men. But, it doesn’t end here…it can affect our babies and the proper development of children: soy phytoestrogens could increase susceptibility to prostate cancer for our preborn baby boys, they could accelerate puberty in developing girls, and harm the reproductive system of females exposed to soy early in life (“…altered ovarian differentiation (i.e., multioocyte follicles), delayed vaginal opening, caused abnormal estrous cycles, decreased fertility, and delayed parturition”). According to the Weston A. Price Foundation, “Toxicologists estimate that an infant exclusively fed soy formula receives the estrogenic equivalent of at least five birth control pills per day. By contrast, almost no phytoestrogens have been detected in dairy-based infant formula or in human milk, even when the mother consumes soy products. A recent study found that babies fed soy-based formula had 13,000 to 22,000 times more isoflavones in their blood than babies fed milk-based formula.” Thankfully, research is exposing the major problems with this popular “health food.”

Though it’s almost impossible to completely avoid hormone disrupting foods, environments, and habits in our modern age, removing soy can make a significant difference.

Here are 3 top reasons to avoid soy:

1. Hormonal disruption to the degree of damaged reproductive systems, suppressed thyroid, and cancer
2. Allergies and sensitivities causing immune response and inflammation 
3. Present in many processed foods that are better avoided in the first place. Soy is often given many different names, including “natural flavors.” Click here to learn some of soy’s different names.

There are many negative aspects of soy, but that doesn’t mean we all must avoid all soy at all times. I appreciate Sarah Pope’s opinion on her blog The Healthy Home Economist: “Please note that fermented soy in small, condimental amounts as practiced in traditional Asian cultures is fine for those who have healthy thyroid function. Only miso, tempeh, natto, and traditionally brewed soy sauce fall under this category. In addition, if you want to sprinkle a few edamame on your salad or have a few small cubes of tofu in your miso soup from time to time, that is fine too. A little soy lecithin in a nonGMO snack food from time to time isn’t necessarily a problem either. Just don’t make it a regular part of your diet!

If you have any sort of thyroid issues going on, however, it is really the best policy to avoid all soy all the time as soy is a potent goitrogen (thyroid suppressor) even if fermented.”

The truth is that I’m happy to avoid most soy, but I love certain soy products. Tamari (traditionally brewed soy sauce) and natto are two favorites of mine. I’ve tried to make natto (and chickpea natto) a couple of times, but it didn’t turn out as well as I’d hoped. Unfortunately, I haven’t found a place to purchase chickpea natto yet as a soy-alternative, but my hopes are high! As for a replacement for soy sauce or tamari, coconut aminos do the trick!

Have you tasted natto? Have you tried to make it?

Additional Reading:

1. Estrogenic foods, such as flax (another popular “health food”!) and soy can trigger precancerous breasts! 1.a.https://www.thehealthyhomeeconomist.com/soy-flax-estrogenic-foods-herbs-trigger-precancerous-breasts/
2. A thorough list of scientific literature demonstrating adverse effects of isoflavones (phytoestrogens found in soy): 2.a.https://www.westonaprice.org/health-topics/soy-alert/studies-showing-adverse-effects-of-isoflavones-1950-2010/
3. Dangers of soy formula and alternatives to it: 3.a.https://www.westonaprice.org/health-topics/soy-alert/why-babies-should-not-be-fed-soy/
   3.b.https://www.thehealthyhomeeconomist.com/why-soy-formula-even-organic-is-so-dangerous-for-babies/