Soy-based foods like tofu, soy milk, miso, tempeh, and edamame are no longer restricted to oddball health-food shops as more Americans explore a plant-based diet for the sake of both their personal health and the world. They're widely displayed at supermarkets, accessible to pour into your latte at the neighborhood coffee shop, and featured in a variety of ways on restaurant menus. They are a protein-packed solution to substitute meat and dairy for vegans, vegetarians, and those who are simply veg-curious. But, with so much conflicting and confusing information available, you may question if soy is genuinely beneficial or dangerous for you.
Let's have a discussion over a glass of soy milk and a piece of tofu-based peanut-butter pie.
What is the nutritional value of soy?
You can eat your stir-fried tofu and drink your soy latte without fear for the most part. "Soy is a great plant-based protein and fiber source. It's low in saturated fat and may help you eat a more balanced diet for less money" Dietitian Amy K. Fischer, RDN, says. "It's a complete protein that includes all nine necessary amino acids, as well as a good supply of B vitamins, fiber, potassium, and magnesium."
"Soybeans have a variety of vitamins and minerals that are important for lowering the risk of chronic illness, as well as fiber that keeps you full and pleased," says Jaclyn London, MS, RD, CDN.
Of course, while deciding which sort of soy to sample, keep in mind that whole foods are usually preferable. Many of the inflammatory articles regarding the "risks" of eating soy are based on soy protein isolate products (think supplements, protein bars and "fake" meats). "The advantages of soy protein isolates, where the protein has been extracted from the soybean, are not the same as the benefits of unprocessed or whole soy," Fischer notes. "Valuable vitamins and minerals are taken out during processing. Furthermore, anything you don't want in your body, such as chemicals, might be introduced."
Why is soy controversial?
Let's go back to the 1990s, when soy foods were initially becoming popular. Many specialists at the time felt that soy may help people combat obesity, heart disease, and even cancer. After all, Asians consume a lot of soy, and studies have shown that they had lower incidences of obesity, heart disease, and breast cancer than individuals in the United States. Soy was clearly the wonder food, right?
Certainly not. Those research focused on correlations rather than causality. Simply because individuals who eat a lot of soy are healthier than those who don't eat soy doesn't suggest that soy is the reason for their better health. Numerous other variables, including heredity, lifestyle, and the remainder of their food, may also be at play.
When researchers looked at what made soy so healthful, they discovered some unexpected results. Isoflavones, estrogen-like chemicals found in soy, were discovered. Furthermore, some research revealed that these substances may accelerate the development of cancer cells, reduce female fertility, and disrupt thyroid function. Soy is also vilified by some health professionals because it has the potential to be an endocrine disruptor, which means it may mimic estrogen in the body and create hormone excess.
Other research, on the other hand, continued to suggest that soy diet might lower cholesterol and assist women manage with menopausal symptoms. While whole soy does include natural plant estrogens, Dawn Jackson Blatner, RDN, a Chicago-based nutritionist, says they're significantly less than genuine human hormones and shouldn't cause concern. When you add it all together, it's easy to understand how this little green bean became a cause of widespread nutritional anxiety.
Experts still don't know all there is to know about soy, just as they don't know everything there is to know about any other food. However, current evidence shows that modest use of minimally processed soy foods (more on that later) is not only safe, but may also have some health advantages.
Today, we may state the following regarding soy:
Soy may help to lower your risk of cancer and other chronic illnesses.
How did soy become associated with the risk of cancer in the first place? It has to do with processed supermarket goods, according to Stephanie Clarke, RDN, a dietitian in Washington, D.C. Soy protein isolates may include higher levels of soy isoflavones, which are chemical substances that may be endocrine disruptors in large doses. Increased quantities of this kind of soy may result in imbalanced hormone levels, which may increase the risk of cancer.
The majority of recent, high-quality research, on the other hand, have concluded that eating unprocessed soy does not raise the risk of breast cancer, and that eating a lot of it may even give some protection. In fact, a review of more than 30 research found that soy consumption lowered the incidence of breast cancer in both premenopausal and postmenopausal women in Asian nations, where soy consumption begins at a young age.
Eating soy may also help to prevent other cancers. Soy intake seems to reduce the incidence of gastrointestinal malignancies and to protect prostate cancer survivors, according to the findings. A high-fiber diet has also been linked to a decreased risk of colon cancer, and soy foods like edamame and tempeh are rich in roughage.
The only time you may want to cut down on soy is if you're pregnant. If you've had an estrogen receptor-positive breast cancer diagnosis before, Clarke advises. If estrogen is a factor, your doctor may urge you to avoid soy entirely.
Soy might aid with fertility and hot flashes.
As long as you don't consume too much, soy looks to be good for fertility. Women who are undergoing in vitro fertilization and have been exposed to BPA in the environment are more likely to get pregnant if they also eat soy. According to studies, this is because soy's isoflavones help counteract BPA's endocrine-disrupting effects.
Just be careful not to overdo it. A study published in the Journal of Nutrition indicated that consuming more than 100mg of soy isoflavones per day (the equivalent of 6-ounces uncooked tempeh or 16 cups soy milk) was connected to decreased ovarian function. Moderate soy intake, on the other hand, was not an issue.
Soy, on the other hand, may help with the uncomfortable and disruptive hot flashes that come with menopause. It may be beneficial, but not for everyone. One Menopause research discovered that women who ate the most soy had much less hot flashes and nocturnal sweats than those who ate the least soy.
If you consume soy instead of beef, your heart is likely to be protected.
Soy may help decrease harmful cholesterol levels, according to early study. However, new research suggests that this isn't the case, and the American Heart Association said in 2008 that there wasn't enough data to claim for sure that soy reduced the risk of heart disease. However, recent study suggests that fermented soy products like natto may protect against cardiovascular disease and cancer. "I was just exposed to natto, a Japanese staple that is less well-known in the United States," Fischer explains. "It's a delectable fermented soybean dish that's often eaten with rice."
One of the healthiest features of eating soy is what it substitutes on your plate: substituting plant foods like soy for animal-based meals decreases saturated fat consumption and increased fiber intake, both of which are beneficial to your heart. In other words, avoiding the steak and instead preparing tofu or tempeh is a heart-healthy choice.
If you have thyroid problems, you should limit your soy consumption.
According to an analysis of 14 research conducted by Loma Linda University, soy meals had no effect on thyroid function in adults with healthy thyroids. If you have an underactive thyroid, however, you should limit your soy intake. According to a 2016 Nutrients review, soy foods may interfere with the body's absorption of thyroid medicine if consumed in excess. Although the data is still inconclusive, physicians recommend waiting at least four hours after eating soy before taking thyroid medication.
Is Soy Actually Beneficial to Your Health?
All of soy's potential advantages come with one caveat: you must choose minimally processed soy products like tempeh, tofu, miso, and edamame to reap them.
These meals provide all of the nutritional benefits of soy without the additional sugar, bad fats, salt, or preservatives found in highly processed foods. Fischer suggests substituting tempeh or tofu for meat in tacos or chili, as well as keeping a bag of frozen edamame on hand for a crunchy snack.
Meat analogs, soy bars, soy yogurts, and protein powders are examples of soy frankenfoods that often only include soy protein isolates rather than whole soybean nutrition. "Removing protein from the other enzymes and bacteria essential for digestion has an impact on nutritional quality," says Taz Bhatia, MD, integrative health specialist and author of What Doctors Eat.
How frequently should you consume soy?
Moderation is the key, as it is with other meals. According to Bhatia, three to five servings of minimally processed soy meals per week is sufficient. Bring it up with your doctor the next time you talk about your diet if you're uncertain or if you have an underlying health problem (like hypothyroidism). Consider integrating more legumes, such as lentils and chickpeas, as well as hemp seeds and quinoa, into your diet if you want to change it up with other plant-based proteins, according to Fischer.
