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So, what do you think about soy? Some say it’s a healthy protein; some say it’s far from healthful. I’ve heard both sides of the story before and wanted to learn some facts about both soy health risks and health benefits for myself.
What is soy? Soy is a legume and part of the bean family. Nutritionally, 1 cup of whole (cooked, boiled) soybeans packs:
254 calories
12 grams of fat
20 grams of carbs
8 grams of fiber
22 grams of protein
It also carries a good amount of calcium, iron, Vitamin C, and magnesium.
The soybean can be processed a million different ways and turned into flour, milk, tofu, vegetable protein, and many other things. Some vegetarians and vegans depend on soy as their main source of protein in place of meat and dairy products.
Beyond the Nutritional Information
The real “meat” of the soy discussion falls outside the nutritional label.
Phytoestrogens – naturally-occurring compounds found in several different plants but really high concentrations are found in soy. Phytoestrogens mimic human estrogen so perfectly that the body processes phytoestrogens as regular ol’ estrogen. If you have thyroid issues or reproductive issues, your radar is up and blinking right now! Phytoestrogens have been shown to have notable effects on the thyroid, reproductive organs, and more.
Anti-nutrients – Remember all that protein and nutrients in soy beans? Yeah, your body won’t be able to use all of it. Some proteins found in soy act as enzyme inhibitors and actually prevent the breakdown of the protein, meaning your body can’t use it. Other chemicals (like phytic acid, for example) prevent the absorption of some crucial nutrients.
Here are a few specific concerns to think about:
Thyroid: A study showed that as little as 30 grams (about 2 tablespoons) of soybeans a day suppressed the thyroid, making it not function properly. Symptoms noted in the study included: malaise, constipation, sleepiness, and goiter. One month after the soybeans were eliminated from the test subjects’ diets, their thyroids bounced back to the previous, normal state.
Menstrual Cycle: A study published in the Journal of Clinical Nutrition found that 60 grams of soy protein per day (that’s about 1-2 cups of soy milk) had a notable effect on the menstrual cycle, delaying it by days. The same results were duplicated with a birth control pill. Actually, the amount of phytoestrogen in about 2 cups of soy milk is equivalent to the estrogen in about FOUR birth control pills. (Disclaimer: Don’t depend on soy milk as a birth control option. It will not work!)
Pancreas: anti-nutrients found in soy protein act as enzyme inhibitors. One example is the blocking of trypsin, an enzyme that breaks down protein so your body can use it. Animal studies have shown that high levels of trypsin inhibitors cause enlargement of the pancreas and even pancreatic cancer.
Breast Health: Even at low doses, soy can have effects on the body. A study found that low doses of soy can increase some enzyme activity the same way that leads to abnormal breast cell growth – cancer.
Brain Health: Don’t age your brain. A study showed that eating more soy in your midlife years was associated with brain atrophy and impaired cognitive function in later life.
GMOs: currently, over 90% of soy crops in the US are genetically modified. If your soy product is not labeled “organic”, then you can be 90% sure it’s genetically modified.
What about all the studies showing the benefits of soy?
Prevents Breast Cancer?
Fact: Women from south Asia are 18% less likely to die from breast cancer than white women.
Why? Many studies have tried to answer that question. In the past, most of these studies looked specifically at the difference in soy intake between the two groups, attributing the lower breast cancer death to a diet higher in soy.
While the studies do show a correlation between soy intake and less cancer, they do not take the whole picture into account. There are MANY factors that contribute to vastly different lifestyles: fish/meat consumption, dairy consumption, alcohol intake, breastfeeding duration, family history, hormonal therapy, and more. Recent research is underway looking at ALL the lifestyle differences that affect breast cancer (and cardiovascular disease).
Cardiovascular Health?
A study found no benefits from soy for endothelium-mediated vasodilation (the opening up of the arteries in response to inflammation).
The same study found that soy had a positive effect on arterial stiffness, reducing artery stiffness which can cause atherosclerosis.
However, subsequent studies have not supported the results. Research continues.
Cholesterol Health?
If reducing your bad LDL cholesterol is the goal, soy won’t be a big help. A study found that replacing half of your daily meat intake with soy did not show significant effects on cholesterol.
Sources of Soy
The educated consumer you are, you probably know that soy is frequently hidden in many of our foods. If you choose to get soy out of your diet, it can be tricky. Here are a few of the more (and less) obvious places you’ll find soy:
Edamame (soybeans in pods)
Hydrolyzed soy protein
Kinnoko flour
Kyodofu (freeze dried tofu)
Mayonnaise
Miso (fermented soy)
Natto
Okara (soy pulp)
Salad dressings
Shoyu sauce
Soy albumin
Soy bran
Soy concentrate
Soy fiber
Soy flour
Soy formula
Soy grits
Soy lecithin (often seen in bread and chocolate)
Soy milk
Soy miso
Soy nuts
Soy nut butter
Soy protein
Soy protein concentrate
Soy protein isolate
Texturized vegetable protein (found in protein bars and veggie burgers)
For a complete list: http://www.kidswithfoodallergies.org/resourcespre.php?id=51.
Is there a good soy option?
If you love your soy, then don’t fret, there are still a few good options for you. Hello, fermented soy! By fermenting the soy, you lose a lot of the troublesome anti-nutrients, allowing normal protein digestion and nutrient absorption. Here are a few examples of fermented soy products:
Natto
Miso
Tempeh
Traditionally fermented soy sauces
Fermented tofu
Fermented soymilk
If you’ve decided to switch up your soy, you’ll probably want to start with a bit of pantry cleaning and replace your soy sauce. Even if anti-nutrients aren’t a big concern for you, you may still want to switch your sauce. I learned that “regular” soy sauce, you know the kind you can buy in the store for $2-4, is pretty heavily processed and artificial. Here’s a quick summary about how regular soy sauce is manufactured:
“Soybean meal and often corn starches are rapidly reduced to their component amino acids using a high-tech process known as “rapid hydrolysis” or “acid hydrolysis,” which involves heating defatted soy proteins with eighteen percent hydrochloric acid for 8 to 12 hours, then neutralizing the brew with sodium carbonate. The result is a dark brown liquid — a chemical soy sauce. When mixed with some genuine fermented soy sauce to improve its flavor and odor, it is called a “semi chemical” soy sauce. Sugars, caramel colorings and other flavorings are added before further refinement, pasteurization and bottling.”
-Healthy Home Economist
How does fermented soy sauce taste? Ah-mazing (and I am incredibly shy to the whole fermentation concept). The “real” stuff tastes way better, because it’s all natural and not a chemical trick. Like all things good and natural, it’s also going to cost more than the cheap stuff. You can find smaller bottles and pay about $2/ounce, but buying a larger size will take it down to about $1/ounce. When shopping for soy sauce, you want an organic, fermented, raw product. You probably won’t find it in the store, so order online.
Perspective
Research is still continuing and exploring more about how soy can affect our bodies. Personally, I already have to limit soy, because I am sensitive to it. I know how difficult it can be to avoid. Almost every salad dressing is made with soy. You’ll also see soybean oil used in crackers and chips, mayonnaise, frozen meals, and more. When it comes to soy, here’s a good guide:
Best Option: an organic, fermented soy product
Better Option: an organic soy product
Good Option: limit/reduce soy consumption
Do you need to make big changes to get soy out of your diet? My personal, non-medical-professional opinion: if you already have thyroid, breast or reproductive issues, continue your soy research and consider cutting out soy.
If making big changes is too difficult or overwhelming right now, don’t stress yourself out. Start by reading labels and becoming aware of where soy is entering your diet. Compare products and look for soy-free options.
Next week…
What if you’re a full-time soy milk drinker? Are there other non-dairy options? Yes! Next week, we’ll look at the world of almond milk. Which brands are good? Any brands to avoid? Can you make it yourself?
The following is part of an Organic Living Journey Guest Post Series now written by Mariana who has a mother’s heart and scientist’s brain.
