The Truth about Soy

Soy is a highly controversial health food. Some people claim it can cure all health illnesses, while others claim it is the number one way to disrupt hormones and cause all the fish in the world to die.

So which is right? Is soy responsible for cancer, ADHD, hormone disruption, and all the other medical ills in the world? Or does it fight cancer, act as a superfood, and heal health woes? Find out below!

What is Soy?

Soy is a legume just like peas, lentils, beans, and peanuts. Anything grown and eaten out of a pod is a legume. Originally, soybeans came from East Asia, but they are grown everywhere now since soy products are used in almost all commercially-processed foods.

When consumed raw, soybeans are toxic. However, when cooked, soybeans are safe to consume. Soy was traditionally made into fermented products, such as natto, miso, tempeh, and tofu.

Today, soy is also used as a protein supplement for vegetarian eaters and is made into milk, dairy substitutes, meat substitutes, and human milk substitutes. Most formula today is made with a soy protein base. A 2011 study published in the American Journal of Clinical Nutrition found that soybean oil accounts for about 7 percent of all the calories consumed in the United States.

After extracting the oil, soybean protein can also be isolated from the beans, which is used as a protein source in many processed foods (particularly baby formula).

What are the Potential Dangers of Eating Soy?

According to a 2013 study published in the journal Entropy, 90 percent of the soy produced in the United States is produced using genetic modification (usually to make it resist pesticides, grow larger, or produce more pods).

Most crops are sprayed with Glyphosate, which the 2013 study linked to adverse health effects. According to the study, Glyphosate inhibits cytochrome P450 (CYP) enzymes, which is an enzyme that removes toxins from the body. Without these enzymes, toxins continue to build up in the body, possibly contributing to chronic inflammation. The article links chronic inflammation with a variety of health problems, including obesity, heart disease, gastrointestinal disorders, depression, infertility, cancer, and Alzheimer’s disease.

Most soy in the United States is consumed through soybean oil- which is in most processed foods. Soybean oil is extracted using a chemical solvent called hexane, which is a toxic substance that is highly controlled. Few tests have been conducted on the long-term risks of ingesting hexane, but according to the National Toxicology Data Network, ingesting enough of the poison can cause respiratory issues and gastrointestinal issues.

Aside from the potential dangers of consuming pesticides and chemicals used to extract soy protein and oil, the beans themselves may have a few unwanted health dangers.

Endocrine Disruption

Soy products contain a large number of isoflavones, which function as phytoestrogens. What this means is that soy can trigger and activate estrogen receptors in the human body just like real estrogen. Estrogen receptors are rather sensitive and can respond to anything that looks somewhat like estrogen (like the soy isoflavones).

The trouble can come when the soy isoflavones disrupt the endocrine system by interfering with the normal hormone balance. Hormones are delicate systems, and when something swings too far one way, it can interfere with the entire way the body functions.

According to a 2006 study published in the Journal of Steroid Biochemistry and Molecular Biology, isoflavones can have two negative effects on the endocrine system (in females as well as males). Either the isoflavones can block real estrogen from binding (meaning the body doesn’t produce enough real estrogen), or the isoflavones can increase real estrogen activity by activating too many estrogen receptors.

Either way, the body’s hormonal system is completely off-kilter, causing hormone imbalances that can lead to other issues.

ADHD

Studies leading back as far as the 1970s have linked the consumption of soy products with symptoms of ADHD.

A study from 2002 conducted by researchers from The University of California-Irvine found that when rats were given concentrations of soy and manganese similar to what babies consumed when they drank soy formula, the rats showed a reduction in dopamine and an increase in attention problems.

A study from 2012 published in the journal Expert Review of Neurotherapeutics confirmed the findings from previous studies. Children with ADHD often have higher levels of manganese, and some studies even showed that mothers who consumed a lot of soy products while pregnant were more likely to have children with ADHD.

Manganese content present in baby teeth at the 5th month of gestation was shown to be an accurate predictor of ADHD risk in children. According to the researchers from the University of California, "The problem with soy is that it is a bio-accumulator of metals. That means soybeans tend to soak up manganese from the earth."

These studies show that too-high levels of manganese is bad for the liver, concentration, and dopamine levels.

Breast Cancer

Studies show that soy isoflavones can have a beneficial effect on the body when it is deficient in estrogen (such as when women are going through menopause).

A study from 2007 published in the Journal Menopause found that isoflavones could reduce menopausal symptoms and reduce bone loss risk. However, other studies show that soy is linked to breast cancer. Some human studies have linked soy with the stimulation of epithelial cells in the breasts, which are the cells most likely to turn cancerous.

There are also human studies showing that soy isoflavones can stimulate the proliferation and activity of cells in the breasts. In a study conducted in 1998 and published in the American Journal of Clinical Nutrition, 48 women were tested for the potential link between soy and breast cancer. The women were divided into two groups with one group eating 60 grams of soy protein a day. After 14 days, the soy group had an increase in epithelial cells.

But strangely, there are also studies that show that women who consume soy products are less likely to get breast cancer. In an observational study review published in the Journal of the National Cancer Institute in 2005, soy intake was associated with a small reduction in breast cancer risk. But the study authors cautioned, “this result should be interpreted with caution due to potential exposure misclassification, confounding, and lack of a dose-response.”

Male Reproductive Health

Men have some estrogen, but obviously much lower levels than women. In some animal studies, an increase in soy isoflavones in the diet during gestation caused reproductive issues later on in the rat’s lives.

In a human study published in 2008 in the journal Human Reproduction, men who ate the highest amount of soy had the lowest sperm counts. But another study found that soy had no effect on sperm count or male hormone production.

A 2009 review published in Nutrition and Cancer on several studies of soy and prostate cancer found that consuming soy products actually had a small reduction in risk of developing prostate cancer. The science is still murky on if soy is dangerous or beneficial to human men, but it appears to be problematic for other mammals.

Thyroid Health

Since soy is an endocrine disruptor, it can also interfere with the thyroid gland, which produces hormones that regulate metabolism and many of the body’s other systems.

A study in Japan published in 1991 (on just 37 adults) found that eating 1 ounce of soybeans each day for three months raised thyroid-stimulating hormone levels, causing complications like malaise, sleepiness, thyroid enlargement, and constipation. When the participants stopped eating the beans, the symptoms went away.

However, more recent studies have shown that soy has little to no effect on thyroid hormones. There is not enough current evidence to solidly conclude that soy products will cause thyroid disruption.

Health Benefits of Soy

• Now that the potential risks of consuming soy are out of the way, let’s take a look at the potential health benefits of soy products. In their whole, complete form (not oil or isolated protein), soybeans contain a wide range of beneficial nutrients. 3.5 ounces of soybeans contain the following beneficial nutrients:

On the other hand, soybeans are also high in phytates, which are substances that can reduce mineral absorption in the body. Soy products have been linked with the following health benefits:

Reduced Cholesterol

Numerous studies have linked soy with the ability to reduce total and LDL cholesterol levels. Some studies have even linked the consumption of soy with a reduced risk in heart disease (but not all).

Breast and Prostate Cancer

Studies also support the idea that consuming soy products may offer a small reduction in prostate cancer and breast cancer risk (which are related cancer types).

Is Soy Healthy?

Studies offer a variety of conflicting messages about soy. For the most part, soy does not seem to be incredibly damaging to the body. On the other hand, the health benefits (aside from basic nutritional value) are also minor. Soy can act as a viable protein replacement for meat, but mainly if consumed in whole, cooked form.

The main damaging effects of soy occur in their processed forms. Soybean oil and isolated soy protein keep all dangerous ingredients while removing all health benefits. Soy can be consumed in whole or fermented form and provide a variety of basic nutritional benefits (and a possible reduction in breast cancer and prostate cancer risk). However, when consumed in oil or isolated protein form, it is extremely dangerous- particularly for individuals with ADHD who may already have too-high manganese and too-low dopamine levels.

If you have ADHD, avoid soy in all forms. It is particularly important for pregnant women to avoid soy as gestation is a critical time for the formation of the endocrine system. Too much soy at this point could be potentially damaging, particularly to boys and babies who will develop ADHD.

Additionally, soy formula is not beneficial for babies and should be avoided, if at all possible. For everyone else, whole soybeans, eaten in moderation, should not cause any major health problems and may provide some health benefits. Just make sure to eat plenty of nutrients along with the soy to counteract the effects of the phytates.