Tofu or not tofu? Soy facts and myths
As an environmentally-minded nutritionist, I often advise my patients to eat less animal protein and more plant-based protein – both for the sake of their own health and the planet’s. One way to do it is by consuming soy products like miso, tempeh, edamame (whole soy beans), soy milk and tofu. But many people need a bit of convincing – not just because they need a bit of inspiration with preparing it, but because soy is surrounded by controversy and misinformation.
Soy is without doubt a nutrient-dense food and an excellent source of protein. The soybean contains all the essential amino acids, as well as an impressive list of micronutrients such as calcium, iron, magnesium, manganese, phosphorus, potassium, B vitamins and zinc. It is also a source of fiber and omega-3 and 6 fatty acids.
Yet despite the powerful health benefits of whole soy foods, myths and misinformation regarding the supposed “dangers” of soy consumption are widely circulated and presented as fact by self-proclaimed “health experts” who aren’t aware of the research. These are the main areas of confusion:
MYTH – ALL soy contains GMOs
GMOs are genetically modified organisms, and their safety for humans is a hot topic. Many European countries have banned them pending conclusive evidence of their harmful effects. Meanwhile, GMOs are everywhere in our food supply and soybeans are one of the major reasons. This is because the biggest consumers of commercially grown GMO soybeans in the world are farmed animals. Currently, 81% of the global soybean crop is genetically modified, and approximately 85% of all GMO soybeans end up in farmed animal feed. The GMO soy consumed by farmed animals does not just magically evaporate in the slaughterhouse or the milk processing plant. It ends up on your plate.
But while an alarming percentage of soybeans are genetically modified, not all soy is GMO. Of the soy directly consumed by humans, non-GMO soy foods such as tofu, tempeh and soy milk are widely available and they are clearly labeled non-GMO.
MYTH – soy causes cancer
Misinformation regarding soy’s relationship to cancer comes from confusion around the phytoestrogens in soy. Phytoestrogen is NOT the same thing as estrogen. Phytoestrogens are naturally occurring plant compounds which are similar in structure to our own estrogen. They can weakly mimic estrogen or block its effects. Estrogen is a steroid hormone that occurs naturally in humans and animals used for food. It helps regulate sexual function and secondary sexual characteristics. While estrogen plays many important beneficial roles, it also naturally promotes proliferation of cells, and at high levels, can increase risk of some cancers by encouraging cells to multiply more quickly.
The concern over soy and cancer stems from the fact that the phytoestrogens (specifically, isoflavones) in soy-based foods react with the estrogen receptor. However, studies have clearly shown that isoflavones do not have the estrogenic effect of inducing tumour growth and actually protect against hormone-dependent cancers such as breast cancer.
Soy does not contain estrogen, but animal foods do!
Everyone knows that animals used for meat and dairy are commonly supplemented with synthetic growth hormones, but sometimes we tend to forget that animal flesh and cow milk also contain naturally occurring estrogen – even “grass-fed” and “organic” animals. Furthermore, meat, dairy and eggs all contain phytoestrogens; they are everywhere in our food, both plant and animal-derived.
Myth: “man boobs”
“Moobs” is another heavily circulated myth with no actual basis in scientific fact. The “soy causes man boobs” urban myth is rooted in the confusion between estrogen and phytoestrogen, but, as previously explained, phytoestrogen is NOT estrogen. If this were the case, there would be a lot of men in need of bras.
In reality, clinical studies in men show that isoflavones do not affect testosterone levels or circulating estrogen levels. Even at levels of isoflavone exposure significantly higher than those of a typical Asian male consuming a soy rich diet, isoflavones have not been found to have feminizing effects.
Much of the fear-mongering around soy is a direct result of misinformation disseminated by the Weston A. Price Foundation (WAPF) relentless fear-mongering. The WAPF is a multimillion dollar operation that lobbies for raw milk and grass-fed beef. Its members (often farmers) make financial contributions and in turn benefit from WAPF promotion. One of the WAPF’s ongoing strategies for promoting animal farming interests is a concerted effort to discredit veganism in general, and soy in particular. The soy industry is expanding exponentially, thus posing a potential threat to the products the WAPF are trying to peddle. In response, the Weston Price Foundation actively publishes articles which spread the supposed dangers of soy consumption, often citing bogus studies to appear credible.
Lessons from Asia
Soy has been a major staple in Asian cultures for centuries, and their incidence of heart disease, cancers, osteoporosis, diabetes, and obesity are all much lower than here in the West. The world’s highest concentration of centenarians live in Okinawa. Regular physical activity, lean BMIs (body mass index), and high consumption of fruits, vegetables and soy are all a part of traditional Okinawan lifestyle. Their aging population enjoy healthier lives and much lower rates of degenerative disease.
Which soy foods are healthiest?
It is sometimes said that only fermented soy foods are safe and healthy to consume, with the eating habits of traditional Asian cultures used to support for this claim. Contrary to this common misconception, the soy products regularly consumed in Asian countries are not all, or even primarily, fermented. In Japan, about half of soy consumption comes from the fermented foods miso and natto, and half comes from tofu and dried soybeans. In Shanghai, most of the soy foods consumed are unfermented, with tofu and soymilk making the biggest contributions. Even in Indonesia, where tempeh is a revered national food, unfermented soy products like tofu account for around half of soy intake.
When it comes to soy foods, I always buy non-GMO products, which are easy to find and are clearly labeled. Thai-style stir fry and tofu scramble are among my favorite tofu dishes; they are easy to prepare and can be made in one pan. I also season and bake firm tofu, then place it in a wrap for a quick lunch. In the winter months, I make creamy vegetable soups with a soy milk base, and grilled tempeh is great on sandwiches and crumbled over salads. If you’re looking for inspiration there are numerous websites and cookbooks which offer delicious soy recipes, ranging from super-easy to gourmet.
For more advice on how soy foods can help with your immune health check out the Foodwise Immune Boost Plan at: https://www.foodwise.life/program/immune-boost
Smoked Tofu Stir-fry
This easy stir-fry highlights fresh, quick-cooking spring greens, combined with tofu. See the note below for suggestions on which leafy greens to use; you can vary it each time. My favorite is baby bok choy!
- 14- to 16-ounce tub firm or firm tofu
- 2 tablespoons olive oil
- 1 medium onion, quartered and thinly sliced
- 1 medium red or yellow bell pepper, or half of each
- 3 cups of various varieties of tender spring greens (larger leaves and usable stalks)
- 1 to 2 teaspoons grated fresh or jarred ginger
- 3 tablespoons reduced-sodium soy sauce or tamari soy sauce
- 1/4 cup or more chopped toasted cashews
- or slivered almonds for topping, optional
- Cut the tofu into 1/2-inch-thick slices. Blot well between clean tea-towels or several layers of paper towel, then cut into 1/2-inch dice.
- Heat half of the oil in a stir-fry pan or wide skillet. Add the tofu and stir-fry over medium-high heat until golden on most sides. Remove to a plate.
- Heat the remaining oil in the same skillet. Add the onion and sauté over medium heat until translucent. Add the bell pepper and continue to sauté until the onion is golden. Add the greens and ginger and stir-fry briefly, just until leaves are wilted.
- Stir in the tofu dice, season to taste with soy sauce, and serve at once. Pass around toasted nuts for topping each serving, if you’d like.
Note: Use one or two Asian greens such as mizuna, tatsoi, or bok choy (or any other Asian greens available to you); or try a combination of spinach with arugula, watercress or even kale.