Soy Good or Bad?

Soy is a controversial topic with a lot of debate in the research for both sides. Here is a brief overview for you.


Soy is used in tofu and various dairy and meat substitutes. Over 90% of soy is produced in the U.S. It is genetically modified and the crops are sprayed with the herbicide Roundup, which may be associated with adverse effects on health. Further, because soy is inexpensive, you are more than likely consuming significant amount of soy every day without even knowing it. To put it in perspective, soybean oil supplied about 7% of total calories in the U.S. diet in the year 1999.

Nutritious or not?

Whole soybeans are rich in micro-nutrients. 100 grams of mature, boiled, whole soybeans contain large amounts of Manganese, Selenium, Copper, Potassium, Phosphorus, Magnesium, Iron, Calcium, Vitamin B6, Folate, Riboflavin (B2), Thiamin (B1) and Vitamin K. This being said they also contain phytates which block absorption of minerals, therefore the micro-nutrients have no benefit.

Soybeans are also a pretty good source of protein. They’re not as good as meat or eggs, but better than most other plant proteins. However, processing soy at a high temperature denatures the proteins and reduce the quality. Although soy may sound good source of nutrients the truth is it has significant effect on the body!

Soybeans are mostly omega 6. As discussed in a previous article Omega 3 vs Omega 6 the western diet is already highly imbalanced in the favor Omega 6 which leads to inflammation. Omega 6 needs to be limited, therefore yet another disadvantage to soy.

Hormonal effect:

The isoflavones found in soy can activate and/or inhibit estrogen receptors in the body, which can disrupt the body’s normal function. This is coupled with numinous issues for both men and women as it causes an imbalance hormone levels.

In women soy is thought to cause mild disruptions in menstrual cycle and increase the risk of breast cancer. For men, even though men only possess a small amount of estrogen, it is believed that estrogen levels are significantly increased with the consumption of soy which can result in a decreased sperm count. However, these findings are still up for debate due to conflicting results.

With all the conflicting evidence, it must be stated that the majority of the studies showing beneficial effects where either sponsored by soy industry or had some financial ties to the soy industry. Therefore, these studies need to be taken with a grain of salt.

My Suggestion:

Limit your soy intake! Although, the evidence is inclusive on the effects of moderate soy intake, there is enough evidence that highlights the adverse effects of large consumption of soy on the body.