There are more than forty thyroid dysfunctions. The medical community divides these dysfunctions into 6 main patterns: 1) primary hypothyroidism, 2) hypothyroidism due to pituitary gland, 3) converting thyroid, 4) overconverting thyroid, 5) elevated thyroid binding globulin, and 6) resistance to thyroid hormone. This article focuses on the third: the converting thyroid.
Thyroid in conversion
Normally, the thyroid gland converts iodine found in food into thyroid hormones. Thyroxine (T4) is the main hormone produced by the thyroid gland, but your body needs to change it into triiodothyronine (T3) to use it. Some patients’ thyroid glands do not handle these conversions adequately and effectively.
Multiple factors can cause underconversion in the thyroid, but one main cause is the production of reverse T3, rather than T3. Your body can’t use RT3, and RT3 doesn’t go back to the usable form T3 either.
The reverse T3 that the thyroid produces basically wastes the thyroid hormone T4. Since the hormones produced by your thyroid affect your metabolic rate, they influence many parts of your body, including your brain, heart, muscles, and liver. Not surprisingly, many patients with autoimmune thyroid disorders also have elevated levels of reverse T3.
What causes thyroid under conversion?
There are tests to identify when a person’s thyroid converts less than T4, but functional medicine looks for the underlying cause.
Many factors can affect the thyroid during conversion, but I have found that stress plays a major role in most patients. Stress comes in many forms, not just from the obvious sources like a demanding job or a strained relationship. Excessive dieting, food sensitivities, and allergies can also stress the body.
Some patients have leaky gut syndrome which allows foreign substances to enter the bloodstream to stress the body. The bodies of other patients feel the stress of exposure to heavy metals, pesticides, and food additives.
All forms of stress cause the adrenal glands to produce cortisol. Normally, stress dissipates and cortisol levels return to normal. However, constant high levels of cortisol inhibit the conversion of T4 to T3 and increase the production of RT3.
How we detect the problem
A TSH blood test is the most widely used tool to assess thyroid function and/or symptoms of a thyroid disorder. Thyroid-stimulating hormone causes the thyroid gland to produce T4 and T3. Although this test may indicate a problem, it does not test for hormonal balance.
Functional medicine strives for optimal hormonal balance, so measurement of other factors such as reverse T3, total T3, T3 uptake, and T4 are also essential in diagnosing and treating an underactive thyroid.
A reverse T3 blood test on your thyroid panel determines if you have high reverse T3. Elevated RT3 levels may indicate additional problems, even when other TSH values may be within normal ranges.
How to Treat High Reverse T3
The conventional medical model generally treats thyroid problems with prescription T4 to bring thyroid-stimulating hormone back to normal levels. Some doctors look beyond the TSH blood test and when they see low T3 levels they prescribe more T3 instead.
Unfortunately, none of these treatments used in the medical model address the various thyroid dysfunctions, much less the 6 major patterns. However, functional medicine does.
Medical and functional models
The medical model focuses on naming the condition (diagnosis) and treating the condition with medication or surgery. Functional doctors want to know why a person’s thyroid behaves the way it does. We do not treat the symptoms, because they can have many causes.
For example, you might have 7 patients with an autoimmune thyroid condition, such as Grave’s syndrome or Hashimoto’s disease, but with 7 different causes. I mentioned that stress is one of the main causes of reverse T3, but it can affect the body in a number of ways.
For example, bacterial dysbiosis (imbalance) in the gut can impede fat digestion and cause blood sugar problems. This causes liver problems, adrenal stress, excess cortisol and increased RT3. Liver problems can also prevent the conversion of T4 to T3.
As you can see, it’s important that we look at more than just your TSH blood test results. Simply changing the medication will not address the root cause of the dysfunction. We cannot independently examine the interconnected systems within your body if we are to understand the root cause of the dysfunction.
The medical model of care is based on specialists. One looks at the thyroid, another looks at the endocrine system, and another looks at the digestive system. Unfortunately, specialization can blind us to what is going on throughout the body. Specialists focus on a single piece of the puzzle, but may never see the whole picture.
Functional model for thyroid disorders
If you have a thyroid condition, it is important to seek care in the functional model, especially if you have an autoimmune thyroid disorder such as Hashimoto’s or Graves’. I think the medical model works well for diagnosing and treating symptoms, but we also need to work with functionality-based care to get to the root cause and restore health.
I want to emphasize that thyroid problems are nothing to play with. If your doctor prescribed any medication, don’t stop taking it just because you read this article. You’ll need to work with a trained functional medicine provider to address the underlying issues so they can help you restore thyroid function before reducing medication.
In some cases, the thyroid may not return to full function and will need ongoing medication. Your functional physician and physician can work as a team to restore your health. It doesn’t have to be one or the other, but a powerful combination of the two.
