soy, the love hate relationship

Soy may be the most controversial health food on the market. It has become a popular component of plant-based diets, but critics question whether soy really produces the health benefits some studies say it does.

On one hand, some studies suggest that consuming soybeans and soy-based products (like tofu) have benefits for cardiovascular health, weight loss, and prevention of certain cancers.

Other studies have suggested that soy may promote the growth of hormone-sensitive breast cancers. It’s also among the most common food allergies.

At the same time, other studies show that soy consumption could cure high cholesterol and help women cope with the symptoms of menopause.

Still other studies suggest that certain estrogen-like compounds found in soy (called isoflavones) could promote the growth of some cancer sells, impair female fertility, and disrupt thyroid function.

Confused? You’re not alone. These conflicting reports have left many people wondering whether to add soy to their shopping carts or swear it off their grocery lists for good. Here’s what I tell my patients:

Good Soy vs. Bad Soy

For the most part, soy-based foods (tofu, edamame, soy milk, miso, tempeh) are classic health foods. Soybeans provide a plant-based protein source that’s packed with a ton of vitamins and minerals that help reduce the risk of chronic disease, along with fiber that helps fill you up so you feel satisfied.

In their least processed form, soy-based foods are highly nutritious and some of the best foods you can eat on the planet.


There are plenty of soy frankenfoods on the market (meat analogs, soy bars, soy yogurts, soy protein powders and supplements) that only contain soy protein isolates, rather than nutrition from the whole soybean. These foods often contain added sugar, unhealthy fats, sodium, or other preservatives usually found in highly processed foods – meaning they are far from nutritious.

Simply spotting ‘soy’ in a product name or nutrition label doesn’t mean you can assume it’s healthy.

This is especially true when it comes to supplements. There is currently little research on breast health and soy supplements, which are more concentrated and stripped of other nutrients.

My Verdict

Soy can be a smart addition to your diet if you eat it the right way. As is often the case when it comes to nutrition, the answer is moderation. Research in recent years has shown that moderate consumption of real, whole soy foods (not the processed variety) likely has some health benefits.

Some forms of soy, like tofu and tempeh, are also healthy alternatives to animal proteins. If soy helps you displace some meat in your diet, I say go for it.

As a general rule, it’s safe to eat two to three servings of soy per week, as long as it’s from a natural source and minimally processed. A single serving could be three ounces of tofu, a cup of soy milk, or a half-cup of edamame.

Still have questions? I’m here to help. Contact my office today to schedule a consultation.