All About That Thyroid - Part 2

5 Minute Read

In part 1 of this series, we talked about how your thyroid functions, the hormones it produces, and why testing for thyroid issues is problematic in conventional medicine. In part 2, let’s talk more about WHY the thyroid struggles.

The majority of thyroid diseases develop because of an autoimmune issue in the body. In these cases, three factors are always present: genetics, stressors, and an unhealthy microbiome. Let’s dig in!


First, thyroid disease is NOT a genetic disease. However, your genetics or DNA is a complicated and dynamic structure. It’s dynamic in that genes can be turned OFF or turned ON.

Several factors, including your environment, food, stress, can all affect which genes are turned off or on. In cases of thyroid disease, the wrong genes are getting turned and end up being detrimental to thyroid function.

Why don’t I feel better on medication? Medication for your thyroid (i.e. giving your body more T4) won’t stop those bad genes from being turned on!


Stressors on your thyroid can be physical, mental, chemicals and toxins. Physical and mental stress on the body can create a situation where the body is trying to protect itself. During times of protection, the body will convert the inactive T4 hormone to reverse T3 (rT3). From part 1 of this series, we learned that rT3 can attach or bind to the thyroid hormone receptors and block its function.

Why don’t I feel better on medication? During times where rT3 is HIGH, thyroid function will be LOW because the receptor is being blocked. Patients taking a synthetic T4 hormone (like Synthroid) will just take this synthetic hormone and turn it into more rT3.

Chemicals and Toxins

Chemicals and toxins can physically block the receptor, deplete nutrients needed for conversion of T4 to T3, deplete nutrients in organs that perform the conversion, block hormone function by creating cellular inflammation, and turn bad genes ON. Proper thyroid function is a complicated process with many steps; chemicals and toxins can block this cascade in many different ways. So, let’s look at some of these chemicals and toxins:

PCBs & Dioxins
    - PCBs and dioxins are found mostly in non-organic meat and dairy.
    - Studies show these toxins induce thyroid hormone metabolism by altering an enzyme in the liver that metabolizes hormones.
    - They can also directly attack the thyroid gland and the proteins that carry the hormone in the blood to all of your other tissues.

    - Numerous studies link pesticides to thyroid disease!
    - A study published in the American Journal of Epidemiology showed that women married to men who use pesticides have almost a 2-fold increase in thyroid disease!

    - Fluoride, bromine and chlorine can cause an enlargement of the thyroid gland.
    - These chemicals are in the same family as iodine and compete with iodine in the thyroid. The number “4” in T4 and “3” in T3 indicate how many iodine atoms are used to make that hormone. So, iodine is VERY important in making thyroid hormones.
    - Both fluoride and bromine are in the water supply in the US.
    - Bromine replaced iodine in bread in the 1980’s and is now in certain soft drinks like Mountain Dew and Gatorade.

    - BPA is found mostly in plastics and cosmetics.
    - Studies indicate that thyroid function changes even at low dosages consistent with what the average person is exposed to in their daily lives.

Heavy Metals
    - Heavy metals with a strong link to thyroid disease are cadmium, mercury, and lead.
    - Mercury has been shown to bind to the hormone receptors because of its affinity for selenium.
    - In studies, mercury has been shown to deplete selenium, which affects the receptor and can trigger an autoimmune response.

Why don’t I feel better on medication? If these stressors are still present in your body, adding more stored T4 hormone isn’t going to change anything!

Unhealthy Microbiome

Another place in your body where T4 converts to the active T3 that can be used by your cells is the gut. We talked in Part 1 of this series how T4 converts to T3 in the liver, which is why we need to have proper liver function for this conversion to even happen. This holds true for your gut and one major player in the gut is your microbiome.

The microbiome consists of all of the microbes (mostly bacteria) that live normally in your intestines. A healthy microbiome consists of good bacteria that help the conversion of T4 to T3. When you have an overgrowth of bad bacteria, this conversion becomes a struggle as the bad bacteria crowd out the good bacteria. An unhealthy microbiome develops for a number of reasons including a poor diet, overuse of antibiotics, stress, too much sugar, and food sensitivities.

Why don’t I feel better on medication? Taking more T4 won’t change the bad bacteria in your gut!

The Takeaway

The best way to start tackling your thyroid problem is figure out the ROOT cause of the problem! If you take medication to add more T4 to your body, you will likely continue to struggle with the same symptoms. Your best first step is to work with a doctor that actually tests for all of the biomarkers necessary needed for proper thyroid function.

If you are interested in working with me, fill out the consultation request below!

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