Understanding the Complexity of Hypothyroidism, Part 1
By Greg Fors, DC, DABCN
One of the most common complaints you as a doctor of chiropractic face on a daily basis is that of chronic fatigue. The only complaint you will hear more often is that of chronic pain. Furthermore, many patients with fatigue have done online research and come in asking you about their thyroid. It is these two issues that behoove you as the doctor, to have a firm grasp of the dynamics of hypothyroidism and its treatment with effective botanicals.
The thyroid hormones control cellular metabolism. In fact, every cell in the body has a receptor for the thyroid hormone. Therefore, when the thyroid system is not working properly, the cells of your patients' bodies and brains can slow down. This can lead to symptoms of fatigue, weight gain, brain fog, depression, digestive problems, sugar cravings and cold hands and feet. Many individuals suffer from hypothyroid symptoms even though their basic thyroid tests are "in the normal range." Additionally, many of your patients will continue to suffer from these symptoms even while taking Synthroid or levothyroxine medication. But doctor, there are natural solutions for these very common symptoms associated with low thyroid function when we look deeper to find the underlying causes.
A Deeper Look
One of the first obstacles you need to overcome is that most patients have not had a comprehensive thyroid workup. The usual approach is to measure a hormone from the pituitary gland called thyroid stimulating hormone (TSH), and sometimes the prohormone from the thyroid gland called Total T4. If the results are within the lab's "normal" range, the patient is told that their thyroid is fine. If the patient's TSH is high and their T4 levels are low, the doctor will many times prescribe T4 as Levothyroxine or Synthroid. But, there are many problems with this simple approach to this complex syndrome.
First, your patient may be just within the normal TSH range, but for their physiology this high "normal" TSH is indicating that their thyroid is decreasing in its ability to produce T4. Presently, TSH 0.5 to 5.0 mIU/L is considered normal for most labs. However, the National Academy of Clinical Biochemistry reported that, "In the future, it is likely that the upper limit of the serum TSH euthyroid reference range will be reduced to 2.5 mIU/L because 95% of rigorously screened normal euthyroid volunteers have serum TSH values between 0.4 and 2.5 mIU/L." I believe, when considering TSH, this reference range should be kept in mind as an optimal for TSH. An optimal value of TSH means the thyroid hormone levels generally match the body's energy needs and/or ability to utilize the energy.
The second issue for you to consider is the role of T4 in the thyroid system. The thyroid gland stimulated by the pituitary's TSH makes the pro-hormone T4 (thyroxine), which exists to become either T3 or Reverse T3. When the body needs energy, it removes an iodine atom from the T4 and turns it into Total T3. A small portion of the protein bound Total T3 becomes unbound or bioactive Free T3. The T4 that eventually becomes bioactive Free T3 (triiodothyronine) enters the cell and enhances ATP production. On the other hand, Reverse T3 is made by removing a different iodine from T4. Reverse T3 acts just as its name suggests. For the cell it's like placing the wrong key in the ignition, it blocks the "working key" T3 from signaling the cell to make energy. It allows the body to turn down the energy when it needs to conserve it.
Just as a car needs a gas pedal and brake pedal for proper function, the same is true for the body. The body needs Free T3 and RT3 to manage its energy needs.
The third issue for you to consider is that most undiagnosed or under diagnosed hypothyroidism today comes from Under Conversion Hypothyroidism and Reverse T3 Syndrome. This is even true for your patients already taking Synthroid or levothyroxine. The problem is this, whether T4 is produced by your thyroid or taken orally, it is not active until it is convert into the biologically active Free T3 "gas pedal." In many individuals, this process of conversion of T4 to Free T3 is insufficient for their energy needs. In these cases you may see a high normal Free T4 with a low normal or abnormally low Free T3, with hypothyroid symptomatology.
When patients are emotionally, physically or biologically stressed, such as being chronically ill, after surgery, after a car accident, aging or even taking drugs like beta blockers, they can produce more Reverse T3. If they are taking T4, Synthroid or levothyroxine, they can convert this into excess Reverse T3, causing hypothyroidism while being on thyroid medication! In these cases when only TSH and T4 are tested, patients will be within normal limits even though they are experiencing marked hypothyroid symptoms. In Reverse T3 syndrome, you end up with relatively more "brake" than "accelerator," and patients develop the symptoms of hypothyroidism. With this their TSH levels and T4 levels many times will be within normal limits. This is the problem when a doctor only runs a TSH and possibly T4; the conditions of Under Conversion Hypothyroidism and Reverse T3 syndrome are never properly diagnosed. To fully understand and diagnose a patient's thyroid condition, you need to consider about eight different thyroid tests: TSH, Total T4, Free T4, Total T3, Free T3, Reverse T3, and calculate the Reverse T3 Total T3 ratio. The minimal tests that I run on a new patient are TSH, Free T4, Free T3 and sometimes Reverse T-3.
Along with these tests, thyroid antibodies levels Thyroid Peroxidase (TPO) and Antithyroglobulin Antibody (ATA) must be checked. This is to determine if you are patient has the most common cause of hypothyroidism today, the autoimmune disorder known as Hashimoto's disease. Below is a chart that may assist you in diagnosing your patient's thyroid issues.
Optimal Thyroid Test Values:
Now that we have a better understanding of how the thyroid system functions and can run a foul leading to the multiple symptoms that you see in your office every day, we need to consider how best to fix the underlying causes of thyroid dysfunction. This will be the subject matter of part two of this article.
Dr. Greg Fors, DC, is the Chief Science Consultant for Biospec Nutritionals, a board-certified chiropractic neurologist (IBCN), certified in Applied Herbal Sciences (NWHSU) and acupuncture. As the clinic director of the Pain and Brain Healing Center in Blaine, Minnesota, he specializes in a natural biomedical approach to fibromyalgia, fatigue, depression, autism and ADHD.