This is the second post in a series on women and hypothyroidism. Start with the first post in this series.
With all women and hypothyroidism, begin at the beginning: test accurately
Initially, I want to find out if you have symptoms of low thyroid hormones. Then I want to see what your labs say. I include thyroid hormone tests with your initial Functional Medicine blood work. If you already have a hypothyroid diagnosis, I still run labs so we can get a clear picture of what type of hypothyroidism you have. There is so much to learn about your hypothyroid condition.
When you are considering getting pregnant, this a must. If you are already pregnant, it is even more of a must. If you are struggling with infertility, comprehensive thyroid assessment is essential. When you are going through menopause, this is another much-needed time for thyroid testing.
Thyroid function is intimately tied to sex hormone function. Times of tremendous sex hormone changes, such as puberty, pregnancy, and menopause, are when thyroid function can take a hit.
What about Hashimoto’s Thyroiditis?
If you are hypothyroid, we expect that your T4 is low, and your TSH is high. However, simply measuring TSH and T4 doesn’t give a complete picture of your type of hypothyroid. It can be a start, but there’s so much missing. These results wouldn’t give any information about autoimmune hypothyroid. In order to test for that, we measure your thyroid antibodies. if you produce antibodies that attack your thyroid, you have a thyroid autoimmune disease. Autoimmune hypothyroid disease is called Hashimoto’s.
Sometimes your antibody tests are within the normal lab range, and are read as negative for Hashimoto’s. However, a one time negative antibody test does NOT mean you are clear. You could have early stage Hashimoto’s. Therefore, I advise antibody testing on a yearly basis, at a minimum.
A caveat on TSH, thyroid stimulating hormone, is that it fluctuates wildly throughout the day. If it’s elevated (meaning a hypothyroid reading), I recommend measuring it every two months while working on the underlying issues. One reason is because you can’t make a judgement call on one TSH reading alone. We also test TSH to measure if our protocols to lower your TSH, and fix your hypothyroidism, are working.
Deeper into Functional Medicine hypothyroid assessment
These tests (TSH, T4, antibodies) are just the starting point. I want a more complete picture. Thyroid physiology is very complex. To find out more, I test the free forms of T4 and T3. A protein called thyroid binding globulin (TBG) carries T4 and T3 hormones in your bloodstream. Then an enzyme cleaves T4 and T3 into free forms – free T3 and free T4. The free forms are what’s available to bind with receptors on cells throughout your whole body, so it’s very important to test these available forms of thyroid hormones. The free forms are what your cells directly use.
Your cells primarily use free T3. T4 converts to T3 in your liver, kidneys, muscles, and intestines. In your intestines, your gut bacteria do the conversion! T4 also converts into an inactive, or junk form, of T3 called reverse T3 (rT3). RT3 can actually take up T3 receptor sites in your cells, which blocks free T3 from getting into your cells.
When free T3 is blocked like this, it causes hypothyroid symptoms. This is not a type of hypothyroidism that can be measured by the conventional means of testing TSH and T4.
In order to determine how well you are converting T4 to T3, I add rT3 to the lab tests, and measure the ratio between free T3 and reverse T3. The ratio should be 20 or higher. If the ratio is low, it tells us that conversion is not optimal, and I follow that path to a myriad of possible causes for this deficit. Conversion problems can happen for women with all types of hypothyroidism, including Hashimoto’s.
The enzymes that do this conversion are called deiodinase enzymes. When I search for conversion problems, I look for factors that interfere with deiodinase function. LOTS of conditions affect the deiodinase enzymes.
Poor enzyme conversion of T4 to T3 does not show up on conventional blood tests.
The types of hypothyroidism include:
- Primary: the problem is in the thyroid gland. Depending on your geographical location, this is primarily due to iodine deficiency or autoimmunity. It can also be from treatment such as radiation, surgery, and many different medications.
- Secondary: the pituitary does not produce enough thyroid stimulating hormone (TSH).
- Tertiary: the hypothalamus does not produce enough thyroid releasing hormone (TRH).
- Clinical or Overt: TSH is elevated and T4 is low.
- Subclinical: minimal or no symptoms, normal T4, but elevated TSH. This is very common, and affects 15% of elderly women in the United States. It can mean Hashimoto’s. It usually results in symptoms and overt hypothyroidism within 10 years. These women are also more likely to have hypercholesterolemia and atherosclerosis.
- Inherited: about 1 in 2000-4000 newborns, symptoms are decreased activity, increased sleep, feeding difficulty, constipation, and prolonged jaundice.
- Autoimmune: Hashimoto’s thyroiditis.
- Gestational: low thyroid that starts in pregnancy, usually caused by iodine deficiency.
- Functional: impaired function of various body systems, such as poor conversion of T4 to T3, other hormone imbalances, gut bacterial overgrowth, insulin resistance, and more.
Summary of Functional Medicine thyroid testing:
A Functional Medicine thyroid blood panel is key. In this panel we test not only thyroid specific markers. We also test for nutrient deficiencies, and reasons for poor conversion. If we find that your hypothyroidism is due to autoimmune Hashimoto’s, that takes us on a deeper track to test for causes of the autoimmunity.
We will uncover your type of hypothyroidism, and get information about how to treat. The thyroid specific markers include: T4, free T4, T3, free T3, reverse T3, T3 uptake, and thyroid antibodies. We may test other markers, especially when you’re hypothyroidism has functional causes.
In the next post we will dive into Step 1 to treating hypothyroid with Functional Medicine. This is all about getting the right nutrients, starting with iodine. In my opinion, we need to start with thyroid nutrition for all women with suspected hypothyroidism.