Why is soy controversial?
In 1999, the FDA declared soy a heart-healthy food on the basis of significant scientific agreement. According to this endorsement, a total of 25g of soy protein per day for adults, as part of a diet low in saturated fat, may reduce the risk of heart disease, keep blood pressure low, and manage cholesterol levels. Keep in mind, however, this only counts for non-processed, organic soy in its original form.
But just a few years after the FDA endorsed soy, countries across the world began banning soy products in infant formula. These bans cited elevated levels of hormonal phytoestrogen in soy, which can affect the growth of a rapidly developing infant. As such, recommendations were updated, advising against feeding an infant soy in order to keep their natural hormone levels balanced. (That said, if you’re interested in incorporating soy into your baby’s diet, ask your pediatrician when organic, unprocessed soy is appropriate to add to their diet for the occasional boost of healthy protein.)
Similarly, some studies have found that too much soy can decrease the male sex drive and lower testosterone levels due to this phytoestrogen increase. Further, soy also contains antinutrients—substances that can block absorption—and protease inhibitors. Because of this, both men and women who eat too much soy will consume too many protease inhibitors, which impairs digestion and can cause bloating or a bellyache.
While a splash of soy milk in your morning coffee may not have a big impact on your health, consuming a diet heavy in soy-based products might. In fact, eating too much soy can skew your body’s natural estrogen levels, causing a variety of symptoms—ranging from eczema to bloating and more.
To that end, women who are already at high risk for breast cancer may potentially increase their risk if processed soy products are a cornerstone of their diet—because processed foods, chemical additives, and preservatives are simply put, unnatural to consume. But it’s crucial to remember nothing affects everyone in the same way. (Interestingly enough, some women felt a reduction in hot flashes and other pre-menopausal symptoms from the estrogen boost from soy in their diet, at a crucial time in their lives when estrogen production tapers off.)
What’s the solution?
If you love soy milk in your morning coffee or cereal, keep portions low (around 4 ounces). If you supplement meat with plant-based protein, make sure you’re eating organic, unrefined soy instead of soy protein isolate. Asian countries get the most out of soy by eating it in fermented forms, such as tempeh, natto, and miso. Fermented soy offers probiotic and prebiotic benefits, fortifying gastrointestinal health and providing a power-packed punch of protein without the pesky preservatives.
At the end of the day, it’s important to be your own health advocate and stay in tune with how certain foods make you feel. Bloating, rashes, and even mood swings and irritability can all present if you have too much soy in your diet—processed or otherwise.
Simply put, to enjoy the perks of soy without any downsides, just be mindful of quantity and quality. If you accept nothing but the best, that just might be how you start feeling.
