Healthy Choice or Hype? Should You Avoid Soy To Safeguard Thyroid Health?

Once reserved as a staple food for vegetarians, many grocery store items contain soy and it’s often hidden as a refined soy ingredient such as soy oil.

The reason?

Food manufacturers regard soy as a cheap, and versatile ingredient.

Soy: Healthy Choice Or Hype?

It’s almost impossible to avoid soy these days. It’s now used in a wide range of processed foods including bread, breakfast cereals, biscuits, crackers, margarine, chocolate, sauces, and soups. It’s also used to make protein products, soy milk, baby formula, soy cheese, soy ice cream, vegetable stock, texturized vegetarian soy protein, soy flour, soy protein bars, soy lecithin, and soybean oil. It’s also widely used in the animal feed industry.

Thyroid and Soy Products To Avoid

Soy protein is made in high tech chemical processing plants. The complex extraction process requires high temperatures, and harsh chemical extraction methods. For example; soybeans are bathed in hexane solvent to extract the protein.

If you have a thyroid disorder you will want to read my special report: Protein Powders For Women {Five Ingredients That Pose a Risk to Your Thyroid Health}

Soy-Based Infant Formulas May Be Harmful to Health

Many parents turn to soy-based infant formulas to help ease allergic reactions. However the biggest problem with soy-based formulas is that they flood the baby’s body with isoflavones.

Isoflavones naturally found in soy are referred to as phytoestrogens (phyto = plant) as they have the ability to mimic estrogen in the body.

What we know from a scientific standpoint is that infants are sensitive to estrogen exposure as they progress though different developmental stages. For this reason, babies and children are at risk when exposed to the estrogen-like effects of the phytoestrogens found in soy.

Furthermore, the two primary isoflavones known as genistein and daidzein can compete for iodine within the body. This may explain why infants given soy-based formula are at higher risk of developing autoimmune thyroid disease.

A History Of Soy In Asian Cultures

In Asia, small quantities of whole bean soy products are considered a traditional staple of the diet. From the simple soybean comes a variety of foods including tofu, natto, miso, tempeh, and boiled soy beans (edamame). These foods are prepared using traditional methods to make these otherwise inedible foods nutritious. Traditional methods such as soaking or long slow cooking make these foods easier to breakdown in the digestive system.

Soy foods are problematic if they are not prepared using traditional methods.

You see, soybeans contain naturally occurring enzyme inhibitors termed phytic acid, or phytates. These compounds make soy difficult to digest, and have the potential to also bind minerals in the digestive system. In this way phytic acid acts as an ‘anti-nutrient’, preventing absorption of vital minerals such as calcium, magnesium, iron and zinc.

This is not good news for thyroid health as the thyroid is particularly sensitive to nutrient deficiencies. For example; iodine, zinc and selenium are three minerals that aid ongoing thyroid hormone activity.

Did you know soybeans contain a much higher phytic acid content than most other grains and legumes?

If you have been over doing soy products you may be low in some essential minerals.

Does Soy Harm The Thyroid?

Yes, soy is harmful to thyroid health as it’s a potent goitrogen. This term is used to describe a food that has the potential to suppress proper thyroid function.

Added to this is the problem of how much soy that has entered our food chain. Western societies are now consuming an increasing amount of soy as highly processed soy ingredients have found their way into a wide variety of foods.

Globally soybean oil has become the most widely used dietary oil. This soy derived oil is routinely used in margarine and shortening. It’s also used in salad dressings, mayonnaise, frozen foods, commercially baked goods and simulated dairy and meat products.

Soy oil along with palm oil and Canola oil are deceptively referred to as ‘vegetable oil’ on food labels. This makes this group of oils sound healthy but the truth is vegetables do not contain dietary oil. It’s clever marketing to make this oil sound healthy to consumers.

The Environmental Impact Of Soy

The biggest shift in farming methods occurred over the last century, particularly with the introduction of ‘monocultures’. These are mega scale farming areas dedicated to a single crop. Soy crops are monocultures that are favoured by large agribusiness to meet growing demand.

As traditional farming methods are lost and the modern monoculture system of production emerges there is an increasing susceptibility of crops to insects and disease. This then pushes up the use of toxic agricultural chemicals. Large soy plantations are viewed by environmentalists as a growing menace. Intense soybean cultivations threaten fragile ecosystems and are taking a significant toll on deforestation of the globe.

Soy and Genetic Engineering

Genetic engineering is the process of using biotechnology to transfer specific traits or genes from one organism into a different plant species. The result is a genetically modified (GM) food. The safety and potential long term health risks of these ‘frankenfoods’ is regularly questioned.

Soy, Canola and corn are the most prevalent GM ingredients.

The first genetically engineered soybeans were planted in the USA in 1996. GM soy now dominates the food industry. Due to this there’s growing demand for food labels to clearly state if genetically modified plants or microorganisms have been used in production.

In the European Union all food, and any ingredients directly produced from a GM source must be labelled even when the GM ingredients may be undetectable in the final product.

The Roundup Ready Controversy

The GM soybean known as the Roundup Ready (RR) soybean was developed by biotech giant Monsanto. This soy plant is resistant to Roundup, a herbicide that contains glyphosate. According the the World Health Organisation glyphosate in Roundup may cause cancer in humans.


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