Should You Eat Soy or Avoid It?

What is the latest evidence for or against eating soy?

Does soy mimic estrogen and create hormonal imbalances, or worse yet, increase cancer risk?

Can eating soy feminize men?

I promise to answer all these questions and more. As is so often the case when I write a blog, I learn of some research from a highly respected authority, for which I know there is no ulterior motive (in other words they don’t work for the soy industry!), and it seems at odds with the current “party line” of what most clinicians in my field of functional nutrition are saying on the topic.

My blog on fish oils, and how the supposed to research on eating fish and heart protection was actually based on faulty research, was such an example; you can read it here.

As I always tell our patients, the field of functional nutrition is not where you should be if you dislike change. We are constantly learning new things, and, unfortunately, sometimes learning of studies purporting “truths” were in fact fiction, due to faulty or privately funded research, thereby skewing results.

OK, back to soy… Soy is a potential allergen or sensitive food, but it certainly isn’t high on the list. In fact, research shows it to have a rather low allergen potential.

Of course when we are speaking of soy, remember we are talking about the whole food – eating the beans themselves, edamame, tofu. We are not speaking of processed foods that contain soy in some fashion, nor soy protein isolate which is far from whole food.

Do you react negatively to soy? If you seem to, the first thing I recommend is to avoid it while we assist you to strengthen the health of your gut and immune system. Once we feel we’ve accomplished that, then we will re-introduce soy in its organic, whole form. For many individuals, that is all that’s required to again enjoy soy and its benefits.

Concerns regarding soy

Soy has long been a staple in Asian diets where breast cancer rates and other chronic degenerative diseases occur at a substantially reduced rate when compared to the U.S. Yet when Asian women migrate to the U.S. and adopt our diet, they lose that protection and their risk rises for heart disease and cancer.

The controversy initially began when soy isoflavones, phytoestrogens, were felt to be contraindicated in breast cancer patients or women at risk of developing breast cancer. Further, there was concern that the phytoestrogens could somehow feminize men.

Did the concern have validity? There are two types of receptors in the human body – alpha and beta. The human hormone estrogen and other chemicals and toxins with estrogenic effects bind to the alpha receptors, capable of contributing to an increased risk of breast cancer along with other conditions. This growth-promoting effect of estrogen is its dark side, and it was assumed that since soy contained a Phyto- (plant) estrogen, it too could bind to these alpha receptors and therefore create adverse health effects. Assumptions can be dangerous, as we all know, and this was another such occasion.

The truth about soy

A large amount of research proves the following:

Women who eat more soy enjoy longer survival after breast cancer as compared to their low to no soy counterparts.

Women who ate the most soy in their youth showed a decrease risk for breast cancer.

Soy helps repair the DNA of damaged genes.

Soy enhances the activity of tumor suppressor genes – it’s always a good idea to have your tumor suppressor genes functioning to full capacity.

Specific genes, called BRCA (Brak-uh) genes, not only keep cancer cells in check, but they prevent a cell from turning into cancer. As you may recall, it was Angelina Jolie, who brought BRCA genes into our households when she chose to undergo a double mastectomy upon discovering she had a mutation of the gene that dramatically increased her chances of developing breast cancer.

Soy phytoestrogens were found, in research, to “turn back on” the protection afforded by BRCA genes by upregulating their expression by 1000%.

In fact, those at highest genetic risk benefit more from ingesting soy (73% reduction of developing breast cancer), when compared to those not at genetic risk (27% reduction).

Meat consumption, by the way, was found to do the opposite – it increased risk by 97% for those at risk, with a 41% increase for those not at risk.

What were we missing in our prosecution of soy?

Soy phytoestrogens bind to the beta receptors. And guess what, when you activate beta receptors you get an ANTI-estrogenic effect, thereby inhibiting the growth-promoting (cancer cell growth) of actual estrogen.

Aha- that was the missing piece of evidence. And now all the benefits of soy start to make sense and the “fear” that was never actually validated, is found to be just that – an unsubstantiated fear.

What is my current stance on soy? I like it, with the proviso that you consume it in its whole, organic form. Processed soy is no better than processed anything, and GMOs still concerns me. There are still no long term studies on humans consuming GMO foods and until there are many, NOT funded by Monsanto or other corporations who have a vested monetary interest in you consuming their product, I’m reserving judgment, but also recommending you don’t consume it.

Realize a GMO crop allows the farmer to spray copious quantities of the herbicide glyphosate (a highly suspected carcinogen) on to crops because it will kill the weeds but not the crop, in this case, soybeans.  Levels of glyphosate are measured in ppm (parts per million), while concentrations in humans are measured in ppb (parts per billion). A study in Food and Chemical Toxicology found glyphosate to activate estrogen receptors in just a few ppt (parts per trillion)! The study found it increased the growth of estrogen-positive breast cancer cells in vitro (in a petri dish). Obviously the concern is that a very small amount of glyphosate residue found on soybeans is enough to initiate the growth of breast cancer cells.

I would recommend not to risk it – stick with organic soy and enjoy its many benefits.

If your health is not where you want it to be and you’re confused about what to do, we can help.

Contact us for a Free Consultation – Call (408) 733-0400.

If you are not local to us you can still receive help, our Destination Clinic treats patients from across the country and internationally.

We help the world’s busiest people regain, retain, and reclaim their health, energy, and resilience.

References:

Messina M, Messina, VL. Exploring the Soyfood Controversy. Nutrition Today: March/April 2013 – Volume 48 – Issue 2 – p 68–75.

S Thongprakaisang, et al., Glyphosate induces human breast cancer cells growth via estrogen receptors. Food and Chemical Toxicology. 2013 Sep;59:129-36.

R Mesnage, et al. Major Pesticides Are More Toxic to Human Cells Than Their Declared Active Principles. Biomedical Research International. 2014; 2014: 179691.

T Bohn, et al. Compositional differences in soybeans on the market: glyphosate accumulates in Roundup Ready GM soybeans. Food Chemistry. 2014 Jun 15;153:207-15.

Chen FP, et al. Phytoestrogens induce differential effects on both normal and malignant human breast cells in vitro. Climacteric. 2014 Dec;17(6):682-91.

Chi F, et al. Post-diagnosis soy food intake and breast cancer survival: a meta-analysis of cohort studies. Asian Pacific Journal of Cancer Prevention. 2013;14(4):2407-12.

Korde LA, et al. Childhood soy intake and breast cancer risk in Asian American women. Cancer Epidemiology Biomarkers & Prevention. 2009 Apr;18(4):1050-9.

Ziegler RG, et al. Migration patterns and breast cancer risk in Asian-American women. Journal of the National Cancer Institute. 1993 Nov 17;85(22):1819-27.

Shu XO, et al. Soy food intake and breast cancer survival. JAMA. 2009 Dec 9;302(22):2437-43.