To Soy or Not to Soy. That Is the Question

September 12, 2018

I am asked this question all the time, but I realized that I have never really dedicated an entire blog to the topic of soy and the fear that has been created around this humble bean.


Walk into any restaurant, coffee shop or super market and you will see for yourself that there are few foods as versatile or popular as soy products. Soy milk is rich and creamy in a morning latte; tofu can easily star in a stir fry for dinner; crisp green  edamame surely beat chips for a snack. The humble soybean’s presence in our diets has grown over the last several decades due to scientific research showcasing  its potential health benefits, while recognizing the health hazards of animal-based proteins. And with a continuing shift in our demand for plant-based proteins, the trend shows no sign of abating.


Despite its popularity, (or I would say because of it) understanding the health effects of soy has become…complicated, you might say. Studies on soy seem to be published on a daily basis talking about its effects on cardiovascular health to how it impacts our gut microbiome. The extensive and often conflicting (depending on who is funding any particular study) has left us confused and terrified of a wee bean.


I turned to MD Anderson for a sensible take on soy and its impact on our wellness. I have taken the following directly from their website with no editing or commentary from me…until the end of course. You know I won’t go quietly!


“Soy-based foods are a popular alternative for those who want to cut back on or eliminate meat from their diet. But what is soy and can it increase or decrease cancer risks? It’s a hot topic that’s confusing, so let’s start with the basics.


Get protein from soy

Soy is a plant protein full of fiber, potassium, magnesium and other vitamins. Common soy-based foods include tofu, edamame, tempeh, miso and soy milk.


“Soy contains all the essential amino acids that play a role in supporting the body’s vital functions,” says Clare McKindley, clinical dietitian in MD Anderson’s Cancer Prevention Center. “It can be an easy way for people on a vegan or vegetarian diet and those with food allergies to get those required amino acids. But, as with any food, eating in moderation is recommended.”


A moderate amount of whole soy foods is up to three daily servings. Examples of a single serving include: 1 cup of soy milk, 1/2 cup cooked soy beans, 1/2 cup of edamame or 1/3 cup of tofu (or tempeh).


Soy and breast cancer

Because natural soy foods contain isoflavones, similar to estrogen, some people fear that soy may raise their risk for certain cancers. This is because estrogen is linked to hormonally-sensitive cancers like breast cancer.


But according to the American Cancer Society, when it comes to soy, isoflavones may act like estrogen, but they have anti-estrogen properties as well. Some studies even show that people who ate soy were less likely to get breast cancer.


“The current research does not support avoiding whole soy foods, even for cancer patients or survivors,” McKindley says.


Soy might lower the risk of other cancers

Soybeans, soy nuts and edamame all contain fiber. And a diet high in fiber may lower your risks for several cancers, including colorectal cancer.


Studies among prostate cancer survivors indicate that eating soy foods may lower PSA levels. Among men in various stages of prostate cancer, those who consumed soy milk or isolated soy isoflavones saw their PSA levels rise at a slower rate. The effect was stronger in some men than others, making it unclear whether genetics or metabolism made a difference in lowering PSA levels.


A healthy balanced diet can include soy

It’s important to have a variety of foods in your diet, including soy.


“If you’re still uncomfortable adding whole soy foods to your diet yet want to reduce how much animal protein you eat, try these common alternatives: beans, lentils, nuts and seeds,” McKindley says. “The protein (and amino acid) content will vary for each.”


If you want to add soy to your diet, eat fewer processed soy foods, and choose more whole foods like edamame, tofu, tempeh, miso and soynuts. Does that mean you should skip the soy nuggets? Not necessarily. That’s a personal choice. But, remember that a processed soy nugget is just that—processed food. And avoiding processed foods is another way to lower your cancer risk.


If eating certain foods, like soy, gives you anxiety, skip them.


“Consider talking with a dietitian if you have questions about going meatless,” McKindley says. “It’s important to make sure you are getting all the nutrients your body needs. Talking with an expert will help you go in the right direction.”


For me, this information from MD Anderson cuts through the myth and gives us a sense of reality. There’s no alarmism from a special interest group putting forth rumors like soybeans contributing to a lack of brain development in infants or causing thyroid trouble (not affecting and already troubled thyroid, but causing the problem), causing men to lose their libido…you know what I mean. The list is endless. I like the straightforward way in which sensible advice is given about soy. No one is running around with their hair on fire.


And the article gives you an out…and I agree. If you don’t want to eat soy, don’t. But don’t skip it out of unfounded fear.


One last thing. If you choose to eat soy, please always choose organic soy products to avoid genetically modified beans as much as we possibly can. Because GMO’s are some truly scary stuff!


While research on soy is ongoing, a few things are clear to me: traditional soy offers a variety of health benefits. It’s a high-protein alternative for those looking to incorporate more plant-based foods and healthy fats into their diet. It’s why the 2015-2020 Dietary Guidelines for Americans assert that a healthy eating pattern can include a multitude of soy products. 


So give it a go. You might just like how you feel.