Soy is often considered one of the most polarizing products. In fact, depending on whom you ask, it’s often classified as either a potent superfood or a dangerous hormone disruptor. Let’s separate fact from fiction, including some new research about soy foods and breast cancer.
Like all foods, soy milk has both benefits and drawbacks that need to be considered, and not all soy products are created equal. For instance, although high-quality, organic soy could potentially fit into a healthy diet, consuming excessive amounts of highly processed soy milk is not recommended.
What Is Soy Milk?
Soy milk is a beverage that is made from soybeans that have been soaked and ground up. The mixture is then boiled and filtered to produce a smooth, creamy consistency.
Store-bought soy milk may also contain other ingredients like flavorings, emulsifiers and fillers, along with added vitamins and minerals to help boost the nutritional value.
It’s often used as a milk alternative for those following a dairy-free diet due to its similarities in taste and texture. It’s often chosen by those unable to tolerate milk products, such as those with a milk allergy or lactose intolerant.
Plus, soy milk can also be swapped in for cow’s milk in cooking and baking recipes to give your favorite dishes a delicious, dairy-free twist.
Nutrition Facts
The soy milk nutrition profile is high in protein, manganese, selenium and copper and provides a low amount of soy milk calories in each serving.
One cup (about 243 grams) of unfortified original soy milk contains the following nutrients:
- Calories: 131
- Total Carbohydrate: 15.3 g
- Fiber: 1.5 g
- Sugar: 9.7 g
- Total Fat: 4.3 g
- Saturated Fat: 0.5 g
- Polyunsaturated Fat: 2.3 g
- Monounsaturated Fat: 1 g
- Trans Fat: 0 g
- Cholesterol: 0 mg
- Protein: 8 g
- Sodium: 124 mg (5% DV*)
- Manganese: 0.5 mg (27% DV)
- Selenium: 11.7 mcg (17% DV)
- Copper: 0.3 mg (16% DV)
- Magnesium: 60.7 mg (15% DV)
- Phosphorus: 126 mg (13% DV)
- Folate: 43.7 mcg (11% DV)
- Thiamine: 0.1 mg (10% DV)
- Riboflavin: 0.2 mg (10% DV)
- Calcium: mg (% DV)
- Vitamin C: mg (% DV)
*Daily Value: Percentages are based on a diet of 2,000 calories a day.
Keep in mind that the nutritional value can vary quite a bit depending on the brand and variety. For example, the homemade soy milk nutrition profile may be lower in calories and protein but higher in certain micronutrients.
Compared to cow’s milk, soy milk is lower in fat but boasts a similar amount of protein in each serving. Both are a good source of several key vitamins and minerals and are often fortified with added micronutrients, such as vitamin D, to help you meet your needs.
Potential Benefits
Research has unearthed several potential soy milk benefits. For starters, soy contains specific compounds known as isoflavones, which are polyphenols that act as antioxidants in the body.
1. May reduce inflammation
Isoflavones can reduce chronic inflammation, which can be especially beneficial for the prevention of chronic conditions like heart disease, cancer and diabetes.
Plant-based diets rich in foods like soy demonstrate anti-inflammatory effects and lower the risk of chronic disease.
For example, one review of seven studies showed that soy milk consumption lowered two significant inflammatory proteins — c-reactive protein and tumor necrosis factor.
2. May help relieve menopause symptoms
One of the main benefits of soy milk for females, in particular, is also thanks to its isoflavones, which can increase levels of estradiol, or estrogen, in the body.
According to a study conducted by the National Institute of Health and Nutrition in Tokyo, soy isoflavone supplements were effective at reducing the frequency and severity of hot flashes, which are a common symptom of menopause.
What’s more, other research indicates that soy protein and phytoestrogens could help promote regular menstrual cycles in women and enhance fertility.
3. May reduce breast cancer risk
Furthermore, despite concerns about the relationship between soy consumption and cancer, some studies have actually found that soy intake could actually help reduce the risk of recurrence for breast cancer while also increasing survival rates.
Indeed, a 2024 meta-analysis of 22 studies concluded that isoflavones may significantly lower the risk of breast cancer recurrence or death.
It may even be linked to a lower risk of other types of cancer as well, including prostate, colorectal and lung cancer.
4. May decrease bad cholesterol
Soy products can also reduce several risk factors of heart disease and improve serum lipid levels. For instance, one study in the British Journal of Nutrition noted that soy consumption was effective at decreasing levels of total and bad LDL cholesterol, along with triglycerides.
Again, the presence of isoflavones appear to be the catalyst. Not only that, but soy milk could also help increase levels of “good” HDL cholesterol, which helps prevent plaque buildup in the arteries.
5. May help one lose weight or manage a healthy weight
Is soy milk good for weight loss? Soy milk is high in protein, which can help promote satiety by reducing levels of ghrelin, the hunger hormone.
However, according to one study in Obesity Science & Practice, including a few servings of soy foods as part of a high-protein diet had no impact on weight loss or fat loss compared to a high-protein diet without soy.
6. May aid sleep quality
Some also recommend drinking soy milk at night, which is thanks to its content of tryptophan, an amino acid that is sometimes used in the treatment of sleep disorders. In fact, a recent 2019 study published in Cureus reported that soybean consumption was associated with improved sleep quality in medical students.
Risks, Side Effects and Downsides
Despite the potential benefits of this popular beverage, there are a few disadvantages of soy milk that need to be considered as well.
First of all, the majority of soy produced in the U.S. is derived from genetically modified crops. For this reason, many people choose to avoid soy altogether due to concerns about the long-term health effects of genetically modified organisms (GMO).
Selecting soy milk brands that are organic is a great way to minimize your exposure to genetically modified organisms. Specifically, minimally processed, non-GMO soy is rich in nutrients and beneficial compounds that can support overall health.
Soy allergies are also relatively common, especially in children. If you experience any food allergy symptoms like hives, stomach pain or redness after consuming any soy products, be sure to discontinue use immediately and consult with your healthcare professional.
Is soy milk bad for men? A review out of Minnesota analyzed the results of several clinical studies and concluded that soy foods had no impact on testosterone levels in men. Not only that, but other studies have also found that regular soy consumption could also be tied to a lower risk of prostate cancer in men as well.
Those with thyroid issues should keep soy consumption in moderation to avoid adverse effects on health. This is because the soy isoflavones found in soy milk can decrease the production of thyroid hormones, which play a key role in regulating everything from metabolism to body temperature.
Conclusion
- Soy milk is a popular milk alternative that is derived from the soybean plant.
- The soy milk nutrition facts boast a good amount of protein, along with important nutrients like manganese, selenium, copper and magnesium.
- Potential benefits of soy milk include reduced symptoms of menopause, improved heart health, better sleep quality, enhanced reproductive health and protection against certain types of cancer.
- If you do decide to add soy milk to your diet, be sure to select a product that is free of added sugar, fillers and questionable ingredients.