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Soy - The Hidden Damage

Soy might be the most concerning food you’re eating. It’s prevalent, overshadowing even sugars and cholesterol as health threats.

The Hidden Health Concerns

Many believe only certain diets heavily rely on soy, but it’s everywhere. Dr. Joseph Hibbeln from the National Institute of Health suggests soybean oil alone could be 10% of an average American’s caloric intake(1).

Beyond obvious soy sources like tofu and soy milk, soy derivatives sneak into packaged snacks, chocolates, sports drinks, bars, and gluten-free products. When they omit wheat flour, they often replace it with soy flour.

What do we mean by ‘Soy’?

  • Tofu: Made from soybean milk curd.
  • Soy sauce: A sushi staple.
  • Soy milk: Mistakenly believed healthier than dairy.
  • Soy flour: A go-to in processed, especially gluten-free, items.
  • Soy protein powder: Common in bars, drinks, and protein supplements.
  • Baby formula: Many budget options have soy.
  • Edamame: Found at many Japanese eateries.
  • Soy ‘meat’: Soy versions of bacon, sausages, and burgers.
  • Soybean oil: Used globally in restaurants and manufacturing.

Before clearing your pantry, let’s dive deeper into why soy may be problematic for your health.

Today, a staggering 82% of soy is genetically modified (GMO). Monsanto, the company behind Glyphosate, introduced the first GMO in 1994. Now, in the USA, 94% of soy crops are GMO-based (2). Unless you’re meticulous about your food sources, you’re likely eating GMO soy.

Why is this concerning?

  1. Glyphosate Presence: GMO soy is ‘Round-Up Ready’, meaning it’s designed to tolerate Glyphosate (Roundup). This results in high glyphosate residues in GMO soy. Non-GMO soy, in contrast, has no glyphosate contamination.(4)
  2. Nutritional Inferiority: Research indicates GMO soy is less nutritious than non-GMO variants.(4)
  3. Genetic Engineering Risks: Consuming GMOs brings unknown health implications. There are connections between GMO soy and issues like sterility, infant mortality, and abnormal growth. 

This article won’t deep-dive into GMO dangers, but for a comprehensive look, consider reading “Seeds of Deception” by J. Smith.

GMO soy has been found to contain an average of 11.9 parts per million (ppm) of glyphosate residues, with peaks up to 20.1 ppm. Contrast this with Monsanto’s 1999 report, which claimed an “extreme” high of 5.6 ppm in their GMO soy tests(6). For context, New Zealand’s tolerance level for glyphosate in fruits is a mere 0.01 ppm. You might wonder why this matters. Glyphosate is intensely toxic. To offer a brief summary on glyphosate:

  • Glyphosate exposure jeopardizes liver health.
  • It changes the expression of 4000+ liver and kidney genes.
  • It can alter our gut microbiome, leading to issues like gut dysbiosis.
  • It may cause bacteria to become antibiotic-resistant.
  • Roundup has been linked to reduced sex hormone production.
  • Glyphosate can heighten estrogenic activity in our body.
  • The World Health Organization’s IARC labeled glyphosate as “likely carcinogenic.”
  • There’s a correlation between glyphosate use and increased miscarriages and premature births.
  • High cancer rates and birth defects are reported in areas with frequent Roundup exposure.

The implications of glyphosate in soy are immense and potentially detrimental to health.

What’s even more alarming is a study revealing the profound effects of glyphosate-contaminated soybeans on pigs, resulting in significant congenital malformations(7).

The researchers observed:

  • Glyphosate was present in various concentrations across all organs and tissues.
  • The lungs and hearts contained the highest concentrations.
  • Affected piglets displayed a range of abnormalities, including:
    • Ear atrophy.
    • Spinal and cranial deformations.
    • A hole in the cranium.
    • Leg atrophy.
    • One instance of a piglet with only a single, enlarged eye.
    • Absence of a trunk.
    • Enlarged tongue.
    • A female piglet possessing testes.

These findings underscore the serious health implications of glyphosate contamination, emphasizing the need for caution and awareness in food consumption.

Soy And Hormonal Disruption: Isoflavones Under Scrutiny

Soy is a significant source of isoflavones, a type of phytoestrogen that has been associated with disturbed endocrine function. At one point, isoflavones were heralded as health enhancers. To illustrate:

Protein Technologies International (a Dupont division) lobbied for a health claim regarding isoflavones, the potent phytoestrogens found abundantly in soybeans. They argued that only soy protein retaining isoflavones could lower cholesterol.

But this view shifted dramatically when the FDA revamped PTI’s petition, omitting any mention of phytoestrogens and instead endorsing soy protein. This change seemingly contradicted the FDA’s own rules.

This unexpected pivot likely resulted from emerging evidence, including findings by US government researchers, suggesting isoflavone toxicity.

Concerns arose about isoflavones’ potential to block minerals, inhibit enzymes, disrupt the endocrine system, cause reproductive issues, and increase soy allergy risks. Notably, despite warning requirements for oestrogen-containing products, soy products remain unregulated in this regard.

A comprehensive review on Soy Isoflavones found:

Though many therapeutic benefits were previously attributed to soy isoflavones, many of these claims lack robust validation from rigorous clinical trials. This discrepancy includes the previously believed link between soy isoflavones and reduced cholesterol, which many researchers and clinical studies now dispute.

Concerning reports have also surfaced, indicating potential adverse effects of soy isoflavones on cognitive function, especially concerning tofu consumption. More alarmingly, recent findings suggest that soy isoflavones could induce cellular chromosomal alterations and even magnify the effects of chemical carcinogens.
The current evidence doesn’t wholly endorse soy isoflavones’ benefits and cautions against their widespread use without conclusive clinical backing(8).

For a deeper dive into isoflavones’ adverse effects, Weston A. Price’s article, “Studies Showing Adverse Effects of Isoflavones, 1950-2013,”is a valuable read, cataloging numerous studies on this subject.

Soy And Its Impact on Estrogen Levels

Soy’s phytoestrogens, which have structures similar to the human hormone estrogen, have raised concerns about their potential hormonal effects, especially in relation to female menstruation and male hormonal health.

One study cited in the Canadian Medical Association Journal evaluated the exposure of male children to diethylstilbesterol (DES), a man-made estrogen. Notably, DES’s effects on animals parallel those of soy’s phytoestrogens. The results were concerning: upon maturation, the exposed boys exhibited smaller-than-average testes(9).

An intriguing n=1 study reported the experience of a 19-year-old male who, after consuming substantial soy amounts for a year, faced issues like diminished libido, erectile dysfunction, and decreased testosterone levels. Thankfully, these symptoms were reversible, as his testosterone levels normalized a year after eliminating soy from his diet(10). However, it’s vital to approach these findings with caution, given the extremely limited study size.

The conversation about soy’s hormonal impacts remains divisive, with data inconsistencies further muddying the waters. What’s certain is that soy’s phytoestrogens do possess biological activity, influencing the body’s hormonal balance in ways yet to be definitively understood.

High Content Of Inflammatory Polyunsaturated Fatty Acids

Polyunsaturated Fatty Acids (PUFAs), while essential for certain bodily functions, have been under scrutiny for their potential negative health impacts when consumed in excessive amounts. PUFAs encompass both Omega 3 and Omega 6 fats.

The primary concern regarding PUFAs is their instability. These fats are vulnerable to oxidation, a process triggered by exposure to heat and light. Once oxidized, PUFAs can promote inflammation within the body, with associated health risks.

A particularly worrisome fact is that many of the oils commonly used for cooking today, notably canola oil and soybean oil, are rife with PUFAs. The consumption of these fatty acids has been linked to a plethora of health concerns, including:

  • Obesity
  • Various types of cancer
  • Illnesses related to inflammation
  • Heart disease
  • Impaired immune function

(Source: AlexFergus.com on PUFAs)

Some health pundits even posit that the surge in PUFAs in our diets is a primary culprit behind many prevalent health maladies today.

The overwhelming use of soybean oil, especially in commercial cooking and food manufacturing, is driven by its affordability.

However, its health implications cannot be ignored. Soybean oil is notably rich in omega 6 PUFA, which is highly prone to oxidation and subsequently promotes inflammation. Specifically, soybean oil is comprised of 57% PUFA fats. For context, olive oil contains a much lower 8% PUFAs, and butter a mere 3%.

This disparity underscores the need for consumers to be vigilant about their dietary choices, understanding the implications of what they’re consuming, and making informed decisions about the fats they incorporate into their meals.

Soy’s Impact On Brain Health

The relationship between soy consumption and brain health is a topic of interest in the realm of nutrition and neurology. A particular article titled “Soy and the Brain” delves into the potential negative repercussions of consuming soy on cognitive function.

As detailed in the article:

An extensive study known as the Honolulu-Asia Aging Study was conducted over a period of three decades and included 3,734 elderly Japanese-American men. This study aimed to find correlations between the consumption of 27 specific foods and drinks and the participants’ health. Among the findings, it was observed that those men who consumed tofu at least twice a week displayed greater cognitive impairment than those who rarely or never consumed tofu(11, 12).

Dr. Lon R. White, the lead researcher from the Hawaii Center for Health Research, stated, “The test results were about equivalent to what they would have been if they were five years older.” However, for participants who did not consume tofu, their cognitive performance was akin to them being five years younger

Additionally, there was a noteworthy observation related to brain atrophy. High tofu consumption during midlife was linked to reduced brain weight. The brain naturally experiences some degree of shrinkage with age. Yet, in men with higher tofu consumption, this typical pattern seemed to be exaggerated, as their brains exhibited more pronounced signs of aging, according to Dr. White.

In summary, it’s important to know that this topic is still hotly debated, and there are a lot of inconsistencies in the data. We do know that soy contains phytoestrogens and does have a lot of biological and hormonal affects on the body.

Soy’s Impact On Hormones

Male Reproductive Health:

  • Several animal studies suggest that soy consumption might influence testicular size, testosterone levels, and testicular expression of steroid hormone receptors.
  • Human studies also indicate potential negative effects of soy on sperm count and testosterone levels.
  • Consumption of soy products like soy flour and soy protein isolates appears to be associated with decreased testosterone levels.

Thyroid Health:

  • There’s evidence suggesting that soy consumption might impair thyroid function.
  • High levels of soy isoflavones in blood may correlate with signs of thyroid disease.
  • Soy formulas might complicate the management of congenital hypothyroidism.
  • Soybeans contain goitrogens, which can interfere with thyroid hormone synthesis and affect iodine status.
  • Animal studies have shown potential negative effects of soy consumption on thyroid health, such as enlarged thyroid glands and goiters.
  • Anecdotal evidence from a small study suggests that replacing soy milk with cow’s milk reduced the size of goiters in children.

Soy contains compounds known as anti-nutrients, which can interfere with the absorption and utilization of various essential minerals. Key among these anti-nutrients are:

  • Phytic acid: Found in many plant foods, including grains and legumes, phytic acid can bind to minerals like iron, zinc, calcium, and magnesium, preventing their absorption in the digestive tract.
  • Oxalates: These can bind primarily to calcium, leading to reduced absorption and the potential for kidney stone formation in susceptible individuals
  • Enzyme inhibitors: Soy contains trypsin inhibitors, which can interfere with protein digestion by inhibiting the action of trypsin, an enzyme responsible for breaking down proteins in the stomach.

Potential Concerns:

  1. Reduced protein digestion: Trypsin inhibitors in soy can impede protein digestion, potentially limiting the availability of essential amino acids and the vitamins and minerals found in protein-rich foods.
  2. Mineral malabsorption: Phytic acid can bind to important minerals, rendering them unavailable for absorption. This may be especially concerning for individuals who rely on soy as a primary source of these minerals.
  3. Increased requirement for certain nutrients: Consuming high amounts of soy might increase the body’s need for some nutrients, like vitamin D and iodine, potentially contributing to deficiencies in these areas.

Several studies have addressed soy’s impact on mineral absorption:

  • Iron Absorption: Two studies highlighted the inhibitory effect of soy products on nonheme iron absorption, a type of iron found in plant foods. Soy’s phytic acid content is considered a primary reason for this reduction in iron bioavailability.
  • Calcium Absorption: Despite soy products often being fortified with calcium to match the levels found in cow’s milk, the bioavailability of this calcium appears to be lower in soy products. This is significant for individuals relying on fortified soy milk as a primary calcium source.
  • Absorption of Multiple Minerals: Another study found that the absorption of calcium, iron, and zinc was inferior in soy milk compared to cow’s milk. This suggests that even when fortified, soy milk might not fully replace the nutritional value of cow’s milk in terms of mineral absorption.

While soy offers a range of nutritional benefits and is a valuable protein source, especially for vegetarians and vegans, it’s essential to be aware of its potential drawbacks.

Individuals who consume significant amounts of soy might want to monitor their intake of key minerals and consider dietary diversity to ensure they’re obtaining a full range of nutrients.

Soy And Its Link To Food Allergies

The prevalence of food allergies appears to be on the rise, with common allergens including peanuts, eggs, dairy, and soy. While the reasons behind the increase in food allergies are multifaceted, soy’s ubiquity in various foods has led some to question its potential role in the growing number of allergic reactions.

Potential Links Between Soy and Allergies:

  1. Asthma Risk: A study involving 1,601 young adults in Australia explored the relationship between dietary choices and asthma risk. The results indicated that while whole milk seemed to offer some protective effects against asthma, soy beverages or soy milk was associated with a heightened risk. However, this does not directly link soy to allergies but rather to asthma, which is a different kind of immune response.
  2. Peanut Allergies: In a longitudinal study monitoring 14,000 infants over two years, babies who consumed soy-based formula were found to have a higher likelihood of developing peanut allergies. Specifically, around a quarter of these soy-consuming babies developed such allergies.

Soy is one of the top eight food allergens, so it’s not surprising that some people have allergic reactions to it.

However, attributing the rise in various other food allergies to soy consumption requires more comprehensive research.

The studies mentioned provide an interesting perspective, but they are not definitive evidence of soy being the primary driver of increasing allergy rates. As always, it’s vital to approach dietary decisions with a balanced view, considering individual health needs and the latest scientific findings.

Soy And Its Link To Cancer

Soy and its relation to cancer is a topic of great debate. While some research supports the anticancer properties of soy, other studies raise concerns about its potential to increase cancer risk. Here’s a balanced look at the evidence:

Evidence Supporting Soy’s Anticancer Properties:

  1. General Observations: Populations that consume a traditional Asian diet, which is high in soy products, tend to have lower incidences of certain cancers, such as breast and prostate cancer, than Western populations.
  2. Isoflavones: Soy is rich in compounds called isoflavones, particularly genistein, daidzein, and equol. Some studies have suggested that these compounds may have anticancer properties, particularly against hormone-sensitive cancers.
  3. Breast Cancer: Some studies suggest that regular soy consumption in childhood and adolescence can reduce the risk of breast cancer later in life.

Evidence Linking Soy to Potential Cancer Risks:

  1. Bladder Cancer: A 2002 study reported an association between soy consumption and an elevated risk of bladder cancer. However, it’s essential to consider that individual studies may have confounding factors and need to be viewed in the context
    of the broader body of research.
  2. Stomach and Colorectal Cancer: A study indicated that soy protein intake might be linked with higher mortality rates from stomach cancer in men and colorectal cancer in women. Again, such studies should be considered in the broader context of
    other research on the topic.
  3. Genistein Concerns: While genistein has been shown to have anticancer properties in some studies, others have raised concerns about its potential to stimulate the growth of cancer cells, especially in high concentrations or specific contexts.

Processing Of Soy And Potential Heavy Metal Contamination

The processing methods used in the production of soy products, especially soy protein isolate, have raised concerns over potential contamination with heavy metals, especially aluminum. Here’s an exploration of this topic:

Soy Processing:

  • Isolated Soy Protein Production: Isolated soy protein, commonly found in many food products, is produced from soybeans using a series of steps. These include removing fibers and other unwanted components to yield a protein-rich product. The process described involving acid washes in aluminum tanks is one method used in producing isolated soy protein.
  • Potential for Aluminum Contamination: The acid wash process can result in leaching of aluminum from tanks, potentially leading to increased aluminum levels in the final soy product.

Health Concerns:

  • Aluminum Exposure: Aluminum exposure in large amounts has been linked to neurological issues and other health concerns. However, it’s important to note that the human body gets exposed to small amounts of aluminum daily from various sources,
    including water, foods, and even antiperspirants.
  • MSG: Some soy products might contain added MSG (monosodium glutamate), which is used as a flavor enhancer. Some people might be sensitive to MSG and experience symptoms like headaches or flushing after consumption. However, the general scientific consensus is that MSG is safe for most people when consumed in typical dietary amounts.

Re-evaluating Soy In Your Diet

The debate around soy consumption has been ongoing, with passionate arguments on both sides. On one hand, soy has been a staple in many Asian diets for thousands of years and is considered a source of protein and nutrients. On the other hand, modern processing methods and the prevalence of genetically modified soy have raised concerns about its health effects.

Key Takeaways from the Discussion:

  • Soy’s Evolution: The soy consumed today differs from what was traditionally consumed. Modern soy often involves genetic modification and extensive processing, potentially introducing new health risks not present in traditionally consumed soy.
  • Traditional vs. Modern Processing: Traditional methods of fermenting soy, as seen in many Asian cultures, reduces many of the potential adverse effects associated with soy consumption. On the other hand, modern methods, especially those resulting in heavily processed soy products, may not offer the same health benefits or safety
  • Fermented Organic Soy: If one chooses to consume soy, opting for fermented, organic soy products like miso, tamari, tempeh, and natto can be a safer and more nutritious choice. These products have gone through a natural fermentation process that can reduce or eliminate many of soy’s potential harmful effects.
  • Awareness & Education: It’s essential to be aware of hidden sources of soy in various products, like soy flour or soy protein isolates. Reading ingredient labels and being informed can help individuals make better choices.
  • Personal Choices: While this article presents various concerns about soy, each individual needs to assess their health, dietary needs, and personal beliefs. Some may choose to eliminate or reduce soy in their diets, while others may continue consuming it, albeit more mindfully
  • Sharing Knowledge: It’s crucial to share knowledge with others and engage in conversations about food and nutrition. Being open to different perspectives can lead to better understanding and more informed choices

In the end, as with many dietary choices, moderation and variety are key.

Continually educating oneself and making informed choices based on personal health needs and preferences will always be beneficial.

Whether you choose to include soy in your diet or not, understanding its potential benefits and risks will help you make the best decisions for your health and well-being.


Leroy Saunders, Pn1. CrossFit L3. ISSA S&C
Email: coach@coachedbyleroy.com
Website: www.coachedbyleroy.com


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