Should You Have Soy Milk? Well, It Depends
6 years ago | Nutrition
By Joy Stephenson-Laws, JD, Founder
Navigating the world of cow’s milk alternatives is, quite frankly, overwhelming! There are many milk options to choose from, including almond milk, oat milk, rice milk, coconut milk, hemp milk, cashew milk and more! And there is a lot of conflicting information about which one is best for you.
But we have to be proactive by looking at our options and weighing the pros and cons of each option. And, honestly, it’s a luxury that we have so many milk alternatives to choose from, especially because it has been reported that around 65 percent of the human population has a reduced ability to digest lactose [a sugar found in cow’s milk and other dairy products] after infancy.
“Lactose intolerance in adulthood is most prevalent in people of East Asian descent, affecting more than 90 percent of adults in some of these communities. Lactose intolerance is also very common in people of West African, Arab, Jewish, Greek, and Italian descent,” according to the National Institutes of Health (NIH).
And, of course, those who are vegan or who just prefer to not consume dairy surely appreciate the variety of plant-based milks available.
Now, let’s discuss one of the most popular milk alternatives on the market: soy milk.
Reportedly, soy is the most widely available milk option and was the first plant-based milk to appear on supermarket shelves.”
What exactly is soy milk?
To put it simply, soy milk is made from soybeans, which belong to the legume family.
“Soy milk is created through a pretty extensive process, involving only soybeans and water. Long story short, the soybeans are cooked, ground, and pressed…,” according to one source.
“During the milk-making process, the soybeans are split and the hulls are removed. What's left is ground and pressed. According to Silk (the father of soy milk itself), when the beans are pressed, the okara, or the insoluble fiber, is removed. The okara is later used as animal feed — mostly for organic farmers — as it's high in protein. What's left is separated from the liquid, which is raw soy milk.”
From there, flavor (such as chocolate, vanilla or almond), sugar, vitamins and minerals may be added.
So is soy milk good for you?
I wish there was a ‘yes’ or ‘no’ answer, but like with most topics related to your health there is no simple answer. Each person may be different. So while soy milk may be good for your friend or spouse, this does not necessarily mean that it is good for you. There are so many factors you have to consider, including age, sex, daily diet, whether you have any current health issues and more.
Advantages of soy milk
According to a 2017 study from the Journal of Food Science and Technology, soy milk is a great milk alternative.
“Soy milk, a popular alternative option for more than four decades, was found to be the most comparable to cow’s milk in terms of overall nutrient balance. It’s also the highest in protein of all the alternative milk options studied, with about 7 to 12 grams (and about 95 calories) per 8-ounce serving,” according to this report discussing the study.
“Soy milk also contains phytonutrients known as isoflavones, which may have cancer-fighting properties.”
And most soy milks are fortified with calcium, another essential nutrient we all need to stay healthy and feel our best. Soy milk is also low in cholesterol and saturated fat, unlike ‘full-fat’ cow’s milk.
Some drawbacks of soy milk
Phytic acid found in soy milk may make it difficult for the body to digest some nutrients.
According to a report discussing the 2017 study, “...some scientists have expressed concerns about ‘anti-nutrient’ substances naturally found in soy, like phytic acid, which can make it harder for the body to absorb and digest important vitamins and minerals.”
“PA [phytic acid] has the strong ability to chelate multivalent metal ions, especially zinc, calcium, and iron. The binding can result in very insoluble salts that are poorly absorbed from the gastrointestinal tract, which results in poor bioavailability (BV) of minerals,” reports the National Institutes of Health (NIH).
However, this ability of phytic acid to “chelate minerals has been reported to have some protective effects, such as decreasing iron-mediated colon cancer risk and lowering serum cholesterol and triglycerides in experimental animals. Data from human studies are still lacking. PA is also considered to be a natural antioxidant and is suggested to have potential functions of reducing lipid peroxidation and as a preservative in foods.”
(Phytic acid is only naturally found in plant-based foods. Almond milk also contains phytic acid. For a list of foods that contain phytic acid, click here).
Another possible downside to soy milk is the impact it could have on hormones.
I am sure you have heard that soy milk may have some negative effects on hormones. Soy milk contains very large amounts of phytoestrogens. These are plant chemicals that may imitate or mimic the body's natural estrogen.
“Phytoestrogens are plant derived compounds found in a wide variety of foods, most notably soy. A litany of health benefits including a lowered risk of osteoporosis, heart disease, breast cancer, and menopausal symptoms, are frequently attributed to phytoestrogens but many are also considered endocrine disruptors, indicating that they have the potential to cause adverse health effects as well. Consequently, the question of whether or not phytoestrogens are beneficial or harmful to human health remains unresolved,” according to the NIH.
There are some concerns about phytoestrogens increasing the risk of breast cancer and hyperthyroidism, but other reports suggest those concerns may lack objective support.
More research is needed, but there is evidence which shows that people in Japan, who have access to a lot of soy foods, actually have a lower risk of cancer (specifically breast cancer).
Nevertheless women with existing breast cancer or women who have survived breast cancer may be advised to avoid soy foods as well as phytoestrogen supplements.
Another body of research examined soy formula and its impact on babies. The new research discovered that infant girls fed soy formula were more likely to develop extreme menstrual pain as young adults.
One of the lead researchers and authors was referenced in this NIH report.
“She said that data from previous laboratory animal studies suggest that early-life exposure to genistein, a naturally occurring component in soy formula, interferes with the development of the reproductive system, including factors involved in menstrual pain. She said these studies have also shown that developmental changes can continue into adulthood.”
Soy formula feedings have also been linked to endometriosis and to larger fibroids among women with fibroids. It has also been linked to heavy menstrual bleeding.
“Other studies by NIEHS scientists found that girl infants fed soy formula had changes in the cells of the vagina, including differences in how specific genes are turned on and off.”
So if you have a baby girl who is allergic to dairy, maybe soy formula is not the way to go. It’s always best to first speak with a competent healthcare professional before you decide which milk is best for your infant or child, especially if the baby or child has allergies.
Furthermore, “The American Academy of Pediatrics (AAP) promotes human milk as the ideal source of nutrition for infants. It does not recommend soy formula for babies born prematurely. For full term infants, the AAP recommends soy formula in rare cases where the child’s body cannot break down the sugars in milk or if the family prefers a vegetarian diet.”
Individuals with G6PD deficiency should probably avoid soy products
We previously discussed G6PD deficiency. It is a genetic disorder and the most common human enzyme defect. It is a condition where the body doesn’t have enough of the enzyme glucose-6-phosphate dehydrogenase, or G6PD, which helps red blood cells (RBCs) function normally. Without enough G6PD to protect the red blood cells, they are prematurely destroyed in a process referred to as ‘hemolysis.’ Medical problems such as hemolytic anemia occur when the bone marrow does not make enough red blood cells to replace the ones that are being destroyed.
In the United States, black males are usually the most affected - reportedly 1 in 10 African American males are G6PD deficient. 1 in 5 Indians are G6PD deficient and 1 in 5 Thai people are G6PD deficient.
Individuals with this condition are usually told to avoid legumes (which include soy products) like soy milk because they may trigger the destruction of red blood cells or cause hemolytic anemia in people with G6PD deficiency.
Finally, store bought soy milks sometimes attempt to mimic full-fat cow’s milk by having vegetable oil and thickening agents added to them. So you might want to opt for low-fat versions with no added sugars.
Hopefully, this all makes you more informed and interested in all of the different milk alternatives. Remember, there are likely going to be benefits and downsides to all of these milks. So it’s up to each of you to be proactive and find out which milk is best.
Which milk alternative do you use? Why? Let us know!
Enjoy your healthy life!
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