Soy, good or bad for you?: Get the Truth

Written By


Expert Reviewed By

Dr. Lauryn Lax, OTD, MS

Dr. Lauryn, OTD, MS is a doctor of occupational therapy, clinical nutritionists and functional medicine expert with 25 years of clinical and personal experience in healing from complex chronic health issues and helping others do the same.

To Soy 800X675 1 | Soy, Good Or Bad For You?: Get The Truth

To Soy or Not to Soy? The whole truth–both sides of the story…

If you are not confused about soy foods, you must not be reading news headlines or magazine articles.

For years now, soy has been one of those debated topics it seems no one can fully agree upon.

For the pro-soy camp, we’ve been told that soy-based foods lowers cholesterol, prevents breast and prostate cancer, boosts weight loss, metabolism and bone health. Products such as tofu, soy milk, soy-based infant formula, and meatless “texturized vegetable protein” burgers are widely available.

Before the rise of other popular non-dairy alternatives, like almond milk and coconut milk, soy milk became the holy grail of milk and creamers. Then of course you’ve got all your “heart healthy” cereals, granola bars and powders boasting “extra protein” packed with soy protein. And if you’re opting for a vegetarian or vegan-based diet, soy comes to the “rescue” for the protein supply you need in tempeh, seitan, tofu and edamame.

Then, you’ve got your no-soy advocates, those who claim “soy causes cancer and hormonal imbalances.” Men scare other men off by noting that soy boosts estrogen (and man boobs—or ‘moobs’). Organic meats on shelves claim to be soy-free. And paleo die-hards tell us legumes ferment in our guts and cause gastric distress.

So who and what do we believe?

Unfortunately, the studies from days of old are old…and the more we know about soy, the more apparent it is that there is little—if any—benefit from it at all (with a few exceptions).

The Bottom Line: Before getting into “To Soy or Not to Soy?,” the biggest factor to consider here is that soy is not a necessary or essential food to the human diet—just like dairy foods are not essential to the human diet, or stevia-sweetened Zevia (Coca Cola substitute) or “paleo friendly” tortillas.

That is that.

And, that said, the question as to whether soy is good or not really is minuscule in the scheme of a total balanced diet, where 80-percent of the time, your body is thriving upon the “basic essentials”—Real foods: Fresh veggies (fibrous and some starchy), fresh fruits, healthy fats and oils, meat and fish, nuts and seeds, and lots of water. All these “real foods” boast the vitamins, minerals, amino acids and nutrients the human body needs to digest and work in conjunction with one another.

When we focus on adding those basic essentials to the bulk of our intake, then the question of what to take away, or what to avoid (or not avoid) becomes inconsequential (hello, 20-percent of the time, let life happen).

Since soy is not essential (Meaning: our bodies can get by without soy in our life), then it certainly may find its way into your palate on the occasion that you order edamame along with your sushi, or crave tofu with your stir fry or salad…but, on balance, soy is not a food where our daily protein intake or vitamin and minerals are won.

Ok, now with that out of the way, here’s the 4-1-1 lowdown on soy.

Soy Good Or Bad

1. It is a Real Food (Sort of).

Soy is a legume. Legumes are beans. Beans are found in nature. Soy is natural unprocessed form.

Cool. Real food. Right?


A real food with some protein—even better, right?

Right…sort of.

In fact, soybeans (unlike many other plant-protein alternatives) do contain all the essential amino acids, like creature-proteins do, and is an alternate option for vegan and vegetarians alike to reach their daily protein requirement (approximately .08-1 gram/lbs. of bodyweight per day).

However, these proteins are not always digested or used by the body.

2. Digestion Problems

The problem with all legumes is that, by nature, legumes are also designed to be protected in the wild from predators and weather.

Beans, nuts and grains contain a special shell casing made up of phytates and lectins to help them do just that—not be eaten by other animals or destroyed by vast storms. This is great for the beans and legumes, but not great for our human guts.

Instead of easily breaking down the phytates and lectins, our gut has difficulty breaking down the toxins, as we consume them, the stomach intercepts these guys as if we swallowed small playground pebbles or steel bullets.

Boom. Boom. Boom. Not easily digested.

Phytates also bind up other minerals—like calcium, zinc and iron, leading to mineral deficiencies. And lectins (proteins with a “sweet tooth”), eat away at your body’s own cell membranes, invoking cell injury and death, and lead to GI, immune and systematic dysfunction. In addition, soy also contains protease inhibitors (trypsin), which can block the enzymes that are necessary for the digestion of certain proteins.

So even though it is a good thing that soybeans are a “real food”—their in-digestibility makes them questionable (and that 9-grams of protein in your Kashi cereal insignificant).

3. Cancer & Cardiac Conundrum

Beyond protein and digestion, other hype around soy is the whole cancer and heart disease debate.

Some studies say: “Yay. Soy wards off cancer and heart disease.”

Other studies say: “Nay. Soy causes cancer and heart disease/inflammation.”

It seems as though, in this case, whatever you go looking for you will and can find, and, depending on whom you ask, soy is either a superfood or toxic carcinogen.

Check out Weston A. Price’s history of studies on soy, from 1939-2014, for instance, showcasing both points of view over the span of 75 years.

Harvard revealed the same thing.

And most current research arrives at also the same answers.

The results? Inconclusive.

BIG chances are (aside from soy in your diet, or not in your diet), multiple other health and lifestyle factors do play a HUGE role in the likelihood of cancer and heart disease (or not) in your future.

Things like, the all-around nutrient density of your diet, toxic exposure, microwave use, stress levels, exercise, organic vs. non-organic produce, social connection, and gut health.

Oh yes, gut health.

If there is ONE thing not mentioned in any study on cancer, heart disease and soy…it is gut health.

Perhaps “inflammation” is alluded to in both reference to cancer and heart disease, but from a nutritionist’s perspective, your gut is the gateway to ALL things health (1, 2).

When you gut is a mess or not happy (bacterial overgrowth, intestinal permeability, parasites, indigestion, GERD, low stomach acid, constipation, bloating, gas, disrupted micro biome, etc.), then the rest of your health and systems take a hit.

Disease is directly connected to your gut—80-90% of your immune system and its cells alone are produced in your gut, and when we have a dysfunctional GI system, then inflammation and autoimmunity (i.e. heart disease and cancer) are bound to happen.

Go back to point one above (on digestion) to sense why the ingestion of soy-based products (milks, soybean oil, processed fake meats) may lead to diseases like cancer and heart disease (hello poor digestion).

4. Hormonal Haywire

Hormonal benefit or hormonal disruptor?

Enter the other “great debate” around soy.

Initial claims around soy, boasted the women-boosting benefits that soy provided for curbing hot flashes, boosting bone health and energizing libido and fertility, due to the isoflavones — a class of phytoestrogens— plant-derived compounds with estrogenic activity, found in many soy products.

Similar to our conundrum with the “healthy heart” and “cancer free” claims above, no study has come back 100% conclusive that isoflavens are really positive for your health.

Oregon State University reviewed and synthesized multiple studies around soy and isoflavens, in particular, revealing things like:

“To date, randomized controlled trials examining the effect of soy isoflavones on bone mineral density in postmenopausal women have produced mixed results.”

“Supplementation with isoflavones appeared to be about 40% less efficient than hormone-replacement therapy in attenuating menopausal hot flashes and required more time to reach its maximum effect…”

And, “There is currently little clinical evidence that taking soy isoflavone supplements decreases the risk of incident and recurrent breast cancer.”


It sounds good…however studies so far haven’t provided a clear answer.

Leading us back to point one…If you are NOT digesting your soy in the first place, what benefits are you really getting?

5. Marketing Mayhem

Unfortunately, when it comes to soy, whatever “good” heart-healthy claims we have been told, digger keeping shows that the FDA may not be telling us the whole story.

In 1999, the Food and Drug Administration allowed companies to claim that diets low in saturated fat and cholesterol that also contain soy “may reduce the risk of heart disease.” The claim was based on early (now, dated) research showing that soy protein lowered levels of harmful LDL cholesterol.

Interestingly however, about one year earlier (1998), the Protein Technology International (PTI), requested that a health claim for isoflavones (the estrogen-like compounds found in soy) be the main marker as to whether or not soy is really beneficial for heart disease and overall health.

The PTI wanted the FDA to make it clear that soy with isoflavones still in it (i.e. processed soy products) IS NOT the healthy kind of soy that humans should consume for health benefits. http://home/laurynlax/ , proposing the real-food soy products (like fermented tofu, miso, tempeh and nato) are more on par with the “beneficial soy” we should be eating.

Read, once more: NOT processed foods with soy.

Unfortunately, the FDA decided not to include this little fact, and thus, the great health marketing scheme around soy (and all the health benefits) began (sounding eerily similar to the “big sugar lie,” exposed by the New York Times’ earlier this year, and the ‘eat 3-dairy-a-day’ marketing campaign when excess dairy fat from the low-fat and Skim-milk product creation frenzy, left American grocery stores with an excess of cheese and other dairy products).

Does this come as a shock to you though?

In short: The evidence out there in research is spotty around the health claims about soy, and in order to get you (and I) to eat more soy, or soy-based products (hint: processed foods), the FDA and other marketing ploys have had us believing soy does a body good.

Reality check: Not all sources are created equal.

6. Processing Problems

Soy is in everything. Well almost everything. Especially if you eat processed foods.

Soybean oil, specifically hydrogenated soybean oil, is the evil step-sister of the well-known (and highly disregarded) food additive High-fructose Corn Syrup. These two ingredients, either alone or together, can be found in practically all processed foods, and, along with sugar itself, are huge players in the chronic inflammation, heart-disease and high blood pressure/cholesterol epidemics (formerly blamed on saturated fats).

Collectively, Americans consume more than 28 billion pounds of edible oils annually. That’s about 93 pounds of oils (largely hydrogenated) per person in the United States, and soybean oil accounts for about 65 percent of it.

The fat in soybean oil is primarily omega-6 fat. While we do need some, Americans in general consume FAR too much omega-6 in relation to omega-3 fat (more omega-6 fats are found in processed foods—even “healthy” foods—like bars, cereals, baked chips, crackers and whole wheat breads). And too much omega-6 fat is also associated with increased inflammation.

One of the primary reasons for hydrogenating oil is to prolong its shelf life. Raw almond butter, for example, is likely to go rancid far quicker than Skippy peanut butter for instance (contains soybean oil). The process also makes the oil more stable and raises its melting point, which allows it to be used in various types of food processing that uses high temperatures—lasting longer on shelves (and in your gut).

Soy Good Or Bad

The Verdict

I am big on bottom lines, and if there’s one thing that’s for sure, it is:

The processed, heated, and packaged versions of soy are just like any other processed food—not ideal.

Be it tofurkey, seitan veggie bacon, soybean oil or protein in your granola bar or ‘protein’ chips, Kashi Crunch cereal or Skippy Peanut Butter (soybean oil), processed versions of soy have zero noted health benefits.

The best options?

Real food: a real, whole, based soy source (i.e. not processed, fermented, additive-filled, and as close to the real deal as possible).

Tempeh, Natto, Fermented Tofu, Miso—All in real, whole-sourced, fermented forms can provide you with some protein (especially if you eat a vegetarian/vegan-based diet), and perhaps even boast the heart health and cancer fighting benefits that all the studies talk about.

(Perhaps we are ALL right after all—it just depends on the type of soy you choose).

So, be wary of the type of soy you choose.

As mentioned at the beginning, soy is not essential, but within the context of 80/20 balance, soy may very well find its way into your diet.

Have a burning health, food or fitness question? I LOVE getting questions and inspiration for my next blog post. Simply visit my form right HERE and send me your question or idea!

Join Waitlist We will inform you when the product arrives in stock. Please leave your valid email address below.

No fields found, please go to settings & save/reset fields