The SHOCKING Truth About Soy: Hormones, Cancer, Fertility, Menopause & MORE!

In today’s episode of Bite Back with Abbey Sharp, we’re breaking down some of the biggest myths about soy and separating hormone fearmongering from the actual science. We unpack what phytoestrogens really do, what the research says about soy and hormones, fertility, cancer risk, menopause, and weight management, plus the controversy around GMOs, processing, and antinutrients. If wellness culture has made you afraid of tofu, edamame, or soy milk, this episode is for you. Here’s a run down of what we discussed in today’s episode: Does Soy Mess With Your Hormones? Does Soy Lower Testosterone or Affect Male Fertility? Can Soy Affect Your Period or Fertility? Does Soy Increase Breast Cancer Risk? Is Processed Soy Actually Unhealthy? The Truth About GMO Soy & Pesticides Should You Worry About Soy Anti-Nutrients? Soy for Weight & Blood Sugar Management Soy Benefits for Heart & Bone Health Can Soy Help With Menopause Symptoms? 👩🏼‍💻 RESEARCH LINKS: https://www.sciencedirect.com/science/article/abs/pii/S1530891X20433038 https://www.sciencedirect.com/science/article/pii/S0890623820302926 https://pmc.ncbi.nlm.nih.gov/articles/PMC4693610 https://www.sciencedirect.com/science/article/pii/S0002916523184346 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/29483840F197DC57A2BD0DCEE2A3543F/S2048679022000155a.pdf/role_of_soy_and_soy_isoflavones_on_womens_fertility_and_related_outcomes_an_update.pdf https://europepmc.org/article/MED/19996398 https://extension.psu.edu/glyphosate-roundup-understanding-risks-to-human-health https://www.sciencedirect.com/science/article/pii/S0022316622166344? DISCLAIMER: The content in this episode is for educational and entertainment purposes only and is never a substitute for medical advice. If you’re struggling with with your mental or physical health, please work one on one with a health care provider. If you have heard yourself in our discussion today, and are looking for support, contact the free NEDIC helpline at 1-866-NEDIC-20 or go to eatingdisorderhope.com. — 📚 GRAB MY BOOK: The Hunger Crushing Combo Method ⤵️ Learn how to reach your healthiest weight without dieting using evidence based nutrition strategies. Amazon: https://www.amazon.com/gp/product/0306836793?tag=hacboogrosit-20 More purchase options: https://www.abbeyskitchen.com/hunger-crushing-combo/ 🎙 LISTEN TO BITE BACK WITH ABBEY SHARP ⤵️ Real conversations about nutrition, wellness, diet culture, parenting, and the biggest food debates. https://lnk.to/Bite-Back?utm_source=hoobe&utm_medium=social ⭐ Enjoying the podcast? Follow Bite Back on Apple Podcasts, Spotify, Amazon Music, or wherever you get your podcasts. If you're enjoying the show, leaving a rating or review really helps support it! ✉️ SUBSCRIBE TO MY NEWSLETTER https://abbeyskitchen.myflodesk.com/kd6ijl0y3e 🥞 FREE Hunger Crushing Combo™ E-Book https://www.abbeyskitchen.com/hunger-crushing-combo/ 💪 FREE Protein 101 Guide https://www.abbeyskitchen.com/protein-intake-recommendations/ 📖 MY FIRST COOKBOOK: The Mindful Glow Cookbook Amazon: https://amzn.to/2nev0lf 👩🏼‍💻 COACHING: 🍽️ Feeding Kids Without Diet Culture Webinar Raise confident eaters without food battles, guilt, or diet culture. https://www.abbeyskitchen.com/coaching/ 📈 Business Coaching Build and grow your online brand with proven social media and business strategies. https://www.abbeyskitchen.com/coaching/ 🤝 Personalized One-on-One Coaching Tailored support for content creation, business growth, podcasting, AI, brand partnerships, and more. https://www.abbeyskitchen.com/coaching/ 📱 FOLLOW ME @abbeysharprd Instagram: https://www.instagram.com/abbeysharprd TikTok: https://www.tiktok.com/@abbeysharprd Facebook: https://www.facebook.com/abbeysharprd Pinterest: https://ca.pinterest.com/abbeysharprd 🌐 VISIT MY WEBSITE Healthy recipes, nutrition resources, parenting advice, and evidence based articles. https://www.abbeyskitchen.com 💬 If you enjoyed this episode, please leave me a comment below with your thoughts and let me know what you'd like to see next! With Science & Sass, Xoxo Abbey 🌸 Learn more about your ad choices. Visit megaphone.fm/adchoices

Speaker names marked ? are inferred from speaking time and the show’s known hosts — they are not voice-verified.

• 0:01Speaker 00

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• 0:59Abbey Sharp?

  Soy has been at the center of nutrition debates for years. So of all the rumors, what is actually true? And what does the science actually tell us about its health benefits like protein in comparison to its counterpart dairy? The anti-soy panic may be one of the most disastrous sets of nutrition myths of our generation. Welcome to another episode of Bite Back with Abby Sharp, where I dismantle diet culture rules, call out the charlatans spinning the pseudoscience, and help you achieve food freedom for good. Of all the legumes in the legume family, soy has had a lot of highs and lows in the

• 1:43Abbey Sharp?

  court of public opinion. Depending on what side of social media you're on, it's either now seen as an alternative to menopause HRT or an endocrine-disrupting supervillain. But the research tells us a much more nuanced story. So today, we're going to be separating the soy fear mongering from the facts. And now that I've got my profi, let's talk about why soy, and not chickpeas or lentils or peanuts, is constantly stirring the controversy. And to do that, we really need to interrogate the mother of all soy claims, that soy equals estrogen.

• 2:25Abbey Sharp?

  So this is the myth that drives almost every other health-based soy fear, because soy uniquely contains natural compounds called isoflavone phytoestrogens. And this is where a lot of people get confused. The word phytoestrogen literally means plant estrogen. So many people hear that and assume that soy contains the same estrogen that our bodies produce. It does not. Phytoestrogens are plant compounds that have somewhat similar structures to estrogen, which means that they can interact with some of the same receptors in the body. But they're not the same hormone.

• 3:05Abbey Sharp?

  They bind much more weakly than human estrogen, and they tend to have more selective effects depending on the person, their hormone levels, and the tissue being studied. So in some situations, they may produce a very mild estrogen-like effect, and in others, they may compete with or dampen the effects of stronger androgenous estrogens. It's confusing, I know. So let's take a look at some of the soy health hysteria and where the research shakes out. Claim number one, that soy feminizes men, AKA the offensive man boob hysteria.

• 3:44Abbey Sharp?

  While the whole soy boy argument has, I guess, a nice ring to it, it's a far bigger reflection of hypermasculinity panic than an actual public health concern. The theory goes that because soy contains these plant estrogens, it may inverse men's natural balance of higher testosterone and lower estrogen levels, resulting in men suddenly growing breast tissue, AKA gynecomastia, and also potentially facing infertility due to damaged sperm. Some concerns about soy stem from isolated case reports, including very rare cases of

• 4:23Abbey Sharp?

  breast tenderness or gynecomastia, but these reports typically involve extremely high intakes. Like in one well-known case study, for example, the individual was drinking nearly 12 cups of soy milk every day, far more than what most people consume. Not surprisingly, when we control for confounders in actual peer-reviewed research, we can see that the boys are gonna be alright. In one large meta-analysis of 41 human clinical studies, they found that neither soy protein nor isolated soy isoflavones impacted men's testosterone or estrogen hormones.

• 5:08Abbey Sharp?

  As for sperm and fertility, one study on healthy men found that consuming soy isolates did not adversely affect semen quality, nor was it associated with IVF fertilization, embryo quality, implantation, clinical pregnancy, or live birth rates. Honestly, if drinking soy milk did make breasts grow, we would expect to see huge population-level hormonal problems in Asian cultures, where soy foods have been eaten for generations. And literally every Hollywood plastic surgeon would be put out of business. But as I said, the boys, and also those 90210 docs, are doing just fine.

• 5:52Abbey Sharp?

  This brings me to the next claim, that soy messes with our menstrual cycle. And this one deserves a little bit more nuance. Some small studies have examined soy isoflavone supplements providing 45 to 100 milligrams of isoflavones per day, amounts that are generally higher than what most people consume through soy foods alone. These studies found slight changes in markers such as a longer follicular phase, moderately higher SHBG, and slightly lower free estradiol. For context, 3 ounces of tofu provides around 20 milligrams of isoflavones, while 1 cup of soy beverage contains around 10.

• 6:34Abbey Sharp?

  And when we look at studies examining usual soy food intake, ovulation, IVF outcomes, and ovarian reserve markers, we do not see evidence of hormonal shifts. Instead, human studies show either no meaningful effects, or in some cases, potential benefits for IVF outcomes. In other words, your tofu is not going to wreck your fertility or your cycle.

• 7:02Speaker 00

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• 7:34Speaker 01

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• 8:37Abbey Sharp?

  And that leads us to one of the most highly debated and high stakes concerns about soy, and that is that it causes breast cancer cell growth. Some breast cancers are estrogen receptor positive. And when estrogen binds to those receptors, it can stimulate the cancer's growth. So for years, oncologists were telling their patients to avoid soy products out of fear that the isoflavones might do the same. Except that we now know it doesn't. Soy isoflavones bind far weaker to estrogen receptors, preferentially binding to the ER beta, not the ER alpha receptors associated with estrogen responsive cancer.

• 9:21Abbey Sharp?

  And in some cases, it may even compete with stronger estrogens to bind to that receptor. So when we look at cohort studies and also in meta-analyses, we see that soy consumption is consistently associated with lower breast cancer recurrence. Breast cancer specific mortality also generally trends lower, although that finding is not statistically significant in every analysis. So it's more important to note here that this does not mean soy treats cancer, nor does it mean that high dose soy supplements are beneficial. Rather, the current body of evidence suggests that including whole soy foods such as tofu,

• 10:06Abbey Sharp?

  tempeh, edamame, miso, and soy beverage appear to be safe and may even offer some potential benefits as part of a healthy dietary pattern. So now that we've dealt with the hormone hysteria, the so-called man boobs, the infertility panic, and the breast cancer fears, we need to talk about a different category of soy misinformation. Much of the remaining debate around soy has shifted away from hormones and towards perceptions of processing. But processing alone doesn't determine whether a food is healthy or harmful. Soybeans are one of the world's major agricultural commodities because they are incredibly versatile.

• 10:50Abbey Sharp?

  They appear often in culturally significant foods like tofu, tempeh, miso, natto, soy beverage, and edamame. And they are also used to produce animal feed, soybean oil, biofuels, adhesives, inks, plastics, and other industrial products. Because soy has so many different applications, it's easy to assume that all soy products are the same. But in reality, foods made from soy vary wildly on how they're processed and their nutritional profile. So some people may see that soy could be processed into products that humans would

• 11:29Abbey Sharp?

  never eat directly, and then conclude that all soy foods belong in the same category of processed or unhealthy foods. The health effects of a food depend on its overall nutritional profile, not simply the fact that it has been processed in some way. So collapsing all soy foods into processed junk or Frankenfood because the crop has industrial or highly processed food applications completely ignores how chemistry works. Like, just because soybean oil can become like a biodiesel doesn't mean that edamame is suddenly a biohazard. Nor does the fact that we can process soybeans into a high sodium frozen meatless chicken

• 12:11Abbey Sharp?

  nugget product mean that tofu or soy beverage are now quote-unquote ultra-processed junk. Processed foods are not created equal. In some cases like tofu, where it's literally just soybeans, water, and a coagulant like calcium or magnesium, it is simply making a whole food more easily accessible and digestible. In other cases, it may actually be making a food safer or more nutritious. Another concern people sometimes raise about soy is pesticide use. Like many conventionally grown crops, some soybeans are grown using herbicides such as glyphosate. However, regulatory agencies set very strict limits on pesticide residues in foods, and

• 12:56Abbey Sharp?

  routine monitoring consistently shows that soy foods sold to consumers fall well within established safety limits. So whether you choose conventional or certified organic soy foods, the evidence supports them as safe and nutritious options. The final myth I've got to address here is this idea that soy is full of quote-unquote anti-nutrients that deplete the nutritional value of your meal. Like many plant foods, soy naturally contains compounds such as phytates and tripsin inhibitors, which can bind to certain minerals or interfere with protein digestion. However, here's an important part of the story that often gets overlooked.

• 13:38Abbey Sharp?

  Cooking, soaking, sprouting, and fermenting soy foods significantly reduces these compounds while also improving digestibility and nutrient absorption. This is one reason why some forms of processing, such as the methods used to make tofu, can actually improve a food's nutritional value. And ultimately, any small reductions in nutrient absorption are far outweighed by soy's overall nutritional benefits. And now that we've explained why soy isn't the hormone-wrecking, cancer-causing, testosterone-crushing supervillain that the internet sometimes makes it out to be, let's shift the conversation to what soy can offer as part of a balanced diet.

• 14:22Abbey Sharp?

  The evidence suggests that soy isn't just safe to eat, it can also be a nutritious source of high-quality protein and other important nutrients. So Soy4When is a built-in hunger-crushing combo that can help you reach and maintain a healthy body weight and stabilize your blood sugars because it offers very lean plant-based protein in a low-calorie, high-volume package. Most soy-based products offer around 1 gram of protein per 10 calories, which is a premium ratio when weight loss or blood sugar management is the goal. Soy protein is also a heart-healthy alternative to animal proteins that are high in saturated

• 15:04Abbey Sharp?

  fat, with one large met analysis of 46 trials showing that consuming 25 grams of soy protein per day for about six weeks reduced LDL cholesterol by 3 to 4%. The plant protein in soy is also a really great option for supporting bones, especially calcium-set tofu and fortified soy milks, which are often fortified with nutrients like calcium, magnesium, phosphorus, and vitamin D3. Now, obviously, those attributes benefit everyone, but they become even more critical for us women as we enter midlife and begin the perimenopause pilgrimage. When our natural estrogen levels decline, we tend to see more age-related muscle loss,

• 15:47Abbey Sharp?

  bone loss, increased risk of heart disease, a propensity to gain more belly fat, and other not-so-sexy middle-aged gripes. Thankfully, soy understands the assignment. Early research suggests that the isoflavones in soy may help to modestly reduce common menopause symptoms, including hot flashes, vaginal dryness, and urogenital symptoms. While there's no official recommendations for soy intake during perimenopause or menopause, a lot of the research has used the equivalent of around 40 milligrams of total isoflavones, which translates to around a quarter cup of whole soybeans, 1 and 1/2 cups of soy milk,

• 16:31Abbey Sharp?

  3.5 ounces of extra-firm tofu, or 7 ounces of silken tofu. You know, the funny and unfortunate thing about soy is that we have spent decades now debating whether it's dangerous for us, when if it weren't such an affordable, accessible, and culturally significant staple, the wellness industry would probably have been singing its praises for years. But I guess it's hard to build a billion-dollar industry around a humble bean. And on that note, that is all that I have for you all today. Signing off with Science and Sass, I'm Abbey Sharp. Thanks for listening.