The Tea on Soy and Your Heart
I’ll be spelling the tea on all about SOY.
What comes to mind when someone mentions soy milk, a soy burger, tofu, or a food product containing soy? Over the years, the poor little soybean has gotten a bad reputation to be an unhealthy food additive that causes more harm than good.
So let’s explore this and sort out fact from fiction when it comes to soy.
Let’s start by discussing what is soy. Soy is a plant, a legume, a bean to be exact. It is rich in isoflavones, a type of plant estrogen or phytoestrogen that works similarly to the type of estrogen found in humans but with fewer effects. The macronutrient components of soy make it a great choice for quality nutrition. It contains more plant based protein and fat than other legumes. It is lower in carbohydrates but also provides less fiber. 1 cup of soybeans contains 296 calories, 31 grams of protein, 15 grams of fat, 14 grams of carbohydrates, 10 grams of fiber, and a significant amount of calcium and iron.
Soy is commonly consumed as soybeans, edamame, tofu, tempeh, miso, and various other soy based food products like soymilk, soy burgers, soy cheese, and more.
Edamame is a type of soybean that is harvested when it’s still young and in an immature state. It's soft and green. It’s usually steamed and eaten right from its pod. Versus the soybean is the more mature bean and typically cream or yellowish in color much like what you see in a glass of soymilk.
Let’s talk more about the types of soy and its uses in cooking.
Tofu is commonly thought of when one is referring to a plant based, vegetarian, or vegan way of eating. Tofu is sometimes called bean curd due to its appearance and based on the fact that it is the curdle from soymilk. It’s made from a mixture of soybeans and water with the addition of calcium or magnesium to form it into a pressed block. It can vary in firmness. Tofu is high in protein, a healthy source of plant based fat, and cholesterol free. Firm tofu can be used in dishes as a healthy substitute for meat, eggs, and paneer. One of my favorite details about tofu is that it tastes like nothing at all so it can take on whatever flavor you desire. If you’re missing the taste of BBQ, season your tofu like BBQ. If you’re missing the taste of chicken, season your tofu like chicken. If you want eggs, tofu is a great alternative for your morning scramble.
Silken tofu is unpressed. It has a silky smooth appearance and is more delicate than a firm block of tofu due to the process of the way that it’s made, allowing it to retain more moisture. Because of its silky, smooth texture, silken tofu is great for adding a high protein source to your smoothie and will give it a creamy texture. Silken tofu is also great for making plant based ice cream, sauces, and dressings, and is commonly cut into cubes for soups.
Tempeh is made from fermented soybeans that have been compressed and bound together by a living mold. It is actually less processed than tofu because it's made from whole soybeans. During the fermentation process of tempeh, the soybeans are covered and bound with white mold mycelium. Now wait, don’t get too excited here and shut off this episode before you get this tea. The mold utilized in the fermentation process of tempeh has an important function. It helps with the development of enzymes, which in turn enhance the soybean, break down the less nutritious parts of the soybean, and contribute to the texture, flavor, and digestibility of tempeh which makes it enjoyable for you to consume. Tempeh has a chewy texture and more of a nutty flavor. It is commonly used to make plant based barbecue strips and bacon because of its texture. Tempeh also contains more fiber and more protein than tofu because of its formation with the whole soybean.
Miso, also a soy product, is a thick, fermented paste that is made from a mixture of soybeans, salt, and a type of mold called koji. Miso is commonly used in Japanese cooking and you probably have had miso soup if you enjoy Japanese cuisine. Because of its salty flavor, miso is commonly used in plant based soups, sauces, and dressings.
Soymilk is typically made by blending soaked whole soybeans and water, then heating and filtering to get the creamy, milk product. The various brands that we purchase from the grocery store typically have added vitamins and minerals much like cows' milk and have been pasteurized to make them shelf and refrigerator stable. Soymilk still is a great source of plant based protein and fat and is cholesterol free.
Now that we have discussed the basics of soy and its various products and uses. Let’s dive a bit deeper. This is where our conversation will change a bit in discussing some of the more processed types of soy products out there. These particular food products have contributed to soy being misunderstood.
Food manufacturers have created soy products utilizing soy protein isolate and hydrolyzed soy protein.
Soy protein isolates are prepared by separating the oil, fibers, and carbohydrates from concentrated soy protein utilizing water and acids. When this happens you lose a lot of the nutrients that are naturally occurring in soybeans that actually give you health benefits that we will discuss shortly. And also within this process of developing soy protein isolates, you are left with a product that can actually be harmful to your health. Soy protein isolates are commonly found in processed plant based foods like soy burgers, plant based chicken nuggets, and even commonly found in non-plant based foods and utilized as a cheap additive, filler, or protein enhancing source. So steer clear of plant based meat alternatives and stick with more of the whole food forms of soy like edamame, tofu, tempeh, and miso.
Hydrolyzed soy protein is another ultra processed formulation of soy. It is formed utilizing a process where the moisture is removed from the soybean with the use of a process of chemical additives to achieve this product. This process is a precursor to the common food additive of monosodium glutamate or MSG. And because of this process, products containing hydrolyzed soy protein have been found to contain a significant amount of MSG. MSG has been found to cause physical side effects for many individuals including frequent headaches, flushing, heart palpitations, numbness and tingling, and multiple other symptoms. Hydrolyzed soy protein is commonly utilized in soy sauce, and other seasonings as a flavor enhancing ingredient. One of the key takeaway points, I always like to remind my listeners of is the importance of being a label reader. Take your time when you are purchasing food from the grocery store or ordering online and actually look at the ingredients label. And if you are dining out, ASK QUESTIONS about what is in the food you are being served or what the food is prepared with.
Now that you have been given the Soy 101 course, let's talk about the many benefits of soy.
Soybeans have been consumed by many cultures for centuries. And, the health benefits of soy have been studied even within the American healthcare system for decades.
Research has shown that consuming soy can be helpful in reducing the risk of Breast Cancer and its recurrence, reducing the risk of lung cancer, reducing the risk of colorectal cancer, reducing the risk of prostate cancer in men, reduce the risk of fibroid in women, lower cholesterol levels, reduce the risk of cardiovascular disease, improve bone density and lower the risk for osteoporosis related fractures, and reduce inflammation thereby helping with a number of other health conditions.
So as you can see, there are many reasons to add soy to your diet. In fact, our Food and Drug Administration has formally added soy based foods as a recommended food product in its most recent published data, titled Dietary Guidelines for Americans.
Let’s take a closer look at soy as it relates to heart health.
A 2020 article in the Journal Circulation, which is a journal from the American Heart Association, found that “higher intake of isoflavones and tofu was associated with a moderately lower risk with an 18% less chance of developing cardiovascular heart disease.” Isoflavones are plant based compounds that are found in legumes that have plant based estrogen properties that mimic the hormone human estrogen. While isoflavones are also found in chickpeas, fava beans, pistachios, peanuts, and other fruits and nuts; soybeans contain the highest levels of isoflavones.
In a 2021 statement from the American Heart Association, plant predominant protein sources were the evidence-based dietary guidance given to promote heart health. Soybeans, edamame, and tofu were more specifically recommended within these guidelines. Studies have shown that a higher intake of legumes like soybeans is associated with a LOWER risk for cardiovascular disease.
A study published in the Journal Circulation in the year 2000, concluded that including soy protein foods into one’s diet low in saturated fat and cholesterol is essential to promoting heart health. The authors of this study also found that daily consumption of 25 or more grams of soy protein showed significant improvement in an individual’s cholesterol levels, particularly in improving cholesterol levels for those who previously had high cholesterol levels. The powerful phytochemicals in soybeans have been shown to reduce one’s bad cholesterol or LDL level by 8.2% and increase one’s good cholesterol or HDL by 7% when the study particularly looked at postmenopausal women. A higher HDL level has been associated with protecting one’s heart from cardiovascular disease.
A 1995 study that looked at an analysis of 38 different studies concluded that substituting soy protein for animal protein was shown to decrease one’s total cholesterol by 9.3%; decrease one’s bad cholesterol or LDL by 12.9%; and decrease one’s triglyceride level by 10.5%.
The isoflavones present in soybeans as we discussed have effects that mimic estrogen. The benefits of this effect are what makes soy such a powerful food in lowering bad cholesterol and increasing good cholesterol. These same isoflavones have also been shown to prevent plaque formation in blood vessels, thereby lowering one’s risk of heart attacks and strokes. In fact, a 2021 European study found that when individuals consumed soy based products on greater than 4 days per week, they had a significantly lower risk of death from heart attack when compared with individuals who never or rarely consumed soy.
So the proof is in the science folks.
Now, I know the next question that is always asked is “But isn’t soy bad for you.” Even after all of the research I’ve presented to you showing the health benefits of soy, and there are many more which we’ll address in future episodes on this podcast; I know that there are lingering questions about if soy will mess up all the other hormones in your body and somehow cause health conditions instead of prevent health conditions. So let’s address some of the soy myths.
One of the common myths is that soy causes cancer:
However, in a 2019 statement from the American Cancer Society, they recommended the consumption of soy foods and deemed them healthy and safe. The myth that soy causes cancer comes from mice level studies. However, in these studies, the mice were found to process isoflavones differently than humans and the doses of isoflavones given were much higher than human consumption. So the take home point is to eat the whole food soy products we discussed but avoid isolates of soy and avoid supplements as ultra high concentrations of isoflavones, higher than what one would naturally consume are still being studied and have not been found to be as beneficial.
Another myth is that children shouldn’t consume soy thinking that it will increase the risk of early puberty, increase the risk of breast cancer in girls and lower the levels of testosterone in boys. However, the research shows that children can safely consume soy and the American Academy of Pediatrics recommends soy based foods as a safe and healthy alternative to meat for children. The research also shows that girls who consume soy in childhood may have a DECREASED risk for breast cancer and pubertal hormones are not affected.
There are many other myths out there but we’ll save more for future episodes. But let’s address one last myth regarding all soy, being genetically modified and essentially deemed a “frankenfood.” The truth is that food manufacturers genetically modify and utilize pesticides on a significant amount of the foods we eat. This includes soy based genetically modified foods or GMOs which are commonly used as feed for livestock like chickens, pigs, and cattle, which humans then go on to consume as meat. However, if you are consuming the healthy soybean products we have discussed like tofu, edamame, tempeh, and miso, these foods are easily found as organic and non-genetically modified products. And this also goes back to my point about making sure that you read the labels on the food products that you purchase. You can read the label and find out if genetically modified ingredients are included. And I’ll give you a hint about the most common places you’ll find genetically modified foods and it's clearly written on the packaging if you give it a look; you’ll find it on processed snacks like cheese flavored crackers. I won’t name the brand, but parents concerned about what they feed their children should read the labels.
Now, this brings us to our Ask The Expert segment.
Our focus is still on heart health this month our Ask The Expert question is “Will taking a calcium supplement cause problems with my heart?”
Calcium supplements have been debatable over the past several years regarding whether they are helpful or harmful to an individual.
In the past, calcium supplements were commonly recommended to those individuals needing to treat or prevent bone disease, particularly osteoporosis.
However, the latest research has shown concerns that calcium supplements may increase one’s risk for heart disease including increasing the risk of heart attack. Researchers have found that calcium supplements may increase the number of calcifications and plaque buildup in our blood vessels leading to heart attacks.
This risk was not found to be similar in those who consumed more calcium rich foods instead. There is some thought that our bodies process calcium supplements differently and aren’t able to sufficiently break down and filter out calcium when it is concentrated in a supplement type of form. However, when consumed in calcium rich foods, the body is able to utilize this form of calcium without increasing risks of adverse effects.
So your best option for increasing your calcium intake is through eating calcium rich foods.
Some foods that are high in calcium include broccoli, Brussels sprouts, dark leafy greens like collard greens, kale, and mustard greens. Beans are also high in calcium including soybeans or tofu, chickpeas, and other bean varieties.
Always remember that because something is sold as a supplement over the counter like calcium supplements are; it is not necessarily safe for use. You should always consult with your personal doctor to determine the right supplements, medications, and nutrition plan for you.
The Essence of Health is in You!