The Truth About Soy
If you are like me, you have probably fallen into the trap that soy is bad for you and you should avoid eating it. I can remember hearing it caused breast cancer and if men ate it they would develop breast tissue. I used to have a negative perception of soy and avoided eating it. Once I decided to go plant-based I thought I should look into these rumors and do my research. What I found was quite the opposite.
Soy has many health benefits, including antioxidant and antiproliferation effects on cancer cells, as well as anti-estrogen effects.¹ ² Let me start by explaining how myths like soy may cause breast cancer and men to develop breasts have arisen.
It’s because soy contains phytoestrogens. Phytoestrogens are natural compounds found in plants that have estrogen-like effects on the body, however, here is what most people don’t know. They can also have anti-estrogen effects on the body as well. The theory is that soy acts as an anti-estrogen by competing for estrogen binding sites. Let me break this down.
The body has 2 types of estrogen receptors alpha and beta receptors. Soy prefers to bind to beta receptors, where drugs containing estrogen-like to bind to alpha receptors.¹ It seems like the male and female reproductive organs are primarily regulated by alpha receptors. Where bones, bladder, and the immune system are mediated by beta. The central nervous system and cardiovascular system are regulated by both types of receptors. ¹ ³ What studies found was drugs containing estrogen might increase your risk for breast and other estrogen dominate cancers, but soy did not because of the high affinity for beta receptor binding. ¹ ³
Also, soy helped prevent breast cancer due to its ability to compete for estrogen binding sites. They found beta receptors to have a protective quality, like in bone. It helps increase bone mass and prevents bone loss, resulting in decreased bone fractures. Also, a higher rate of beta receptor binding helps with memory and learning function.¹ ² ³
After reading the research I have completely changed my opinion about soy. Any research I found with possible negative effects of soy on the body would result in a person consuming 30 cups or more of soy products per day which, is a completely unrealistic amount.¹ I will say I am not comfortable eating GMO soy products, so we only buy non-GMO and organic as much as possible.
¹ Greger, M. Who Shouldn’t Eat Soy? NutritionFacts.org Retrieved from: https://nutritionfacts.org/video/who-shouldnt-eat-soy/
² Barnard, N. No Debate: Soy is Beneficial to Health.The Physicians Committee for Responsible Medicine. Retrieved from:https://www.pcrm.org/nbBlog/no-debate-soy-is-beneficial-to-health
³ Paterni, I. Granchi, C. Estrogen Receptors Alpha (ERα) and Beta (ERβ): Subtype-Selective Ligands and Clinical Potential. PubMed. Retrieved from:https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4192010/