When You Drink Soy Milk Every Day, This Happens
Soy milk has had a mixed reputation over the years, to put it lightly. From fears over soy's ability to mimic estrogen in the body to the alleged dangers of the GMO soybeans used to make it (via Empowered Sustenance), conflicting claims about this cow milk alternative might have you thinking you'll sprout frog legs and hop off into the sunset the next glass you drink. The bad news: Research on soy isn't cut and dried. But the good news? If you drink a moderate amount of soy milk every day, you'll probably be fine.
Soy milk is made from soybeans, a legume that is rich in protein and amino acids (via Healthline). Note that soy milk contains fewer of the nutrients you'd find in the whole food (the soybean) but, it's still a good source of protein and might even help you build some muscle mass — at least compared to other alternative milks (via Eat This, Not That!).
A nutritionist who talked to Everyday Health said soy milk was probably the best substitute for cows' milk, but in moderation. And according to a study from The Journal of Nutrition, men and women with high blood pressure who drank soy milk every day instead of cows' milk actually saw their blood pressure decrease after three months.
Drinking soy milk in moderation has its upsides
There's also some evidence suggesting that soy-rich diets can help lower cholesterol, improve fertility, and protect against some kinds of cancer (via Healthline), but some of this evidence comes from studies where people consumed other soy rich and fermented foods, not just milk.
Both soy and soy milk do contain compounds called isoflavones, which are also known as "phytoestrogens" because they can attach to estrogen receptors. These chemicals have been linked to concerns over soy "mimicking" estrogen in the body, but are also the ones credited for many of the health benefits of soy (via Good Housekeeping and Everyday Health).
High consumption of isoflavones has been linked to both fertility problems and benefits (via Healthline), but this conflicting information might have to do with the way the studies were conducted, according to Harvard, like studying the effects of high consumption — we're talking the equivalent of 16 cups of soy milk per day for one of the studies. One cup of soy milk has about 6 milligrams of isoflavones (via Harvard).
While it's always a good idea to consult a professional if you have concerns over soy's effects (some evidence suggests people with a high risk of breast cancer or thyroid problems should limit their soy intake, according to Good Housekeeping and Molecular and Cellular Endocrinology), if you drink one or two servings every day, you're likely to be unaffected, or even gain some of the many health benefits of soy milk.