Thyroid patterns that won’t show up on standard lab panels


So, you are taking medication for your hypothyroidism, but you continue to experience symptoms such as muscle pain, fatigue, weight gain, hair loss, depression, foggy mind and difficulty losing weight. Your doctor asks you to repeat your blood test to assess your thyroid hormone levels, but they are within range. Does that mean everything is normal with your thyroid function? Could these symptoms be in your head?

A standard thyroid panel consists of checking for thyroid stimulating hormone (TSH) and T4. But the normal range of these hormones doesn’t always predict the health of your thyroid gland, a little butterfly shaped gland located at the base of your neck.

The thyroid gland secretes thyroid hormones T3 and T4, which are responsible for regulating several biological processes including your energy levels, metabolism, body temperature, digestion, reproduction and more. When the hypothalamus (a part of your brain) senses low levels of T3 and T4 in blood, it secretes thyrotropin-releasing hormone (TRH) that further signals your pituitary gland to make thyroid stimulating hormone (TSH). The role of TSH is to tell your thyroid gland to make T3 and T4. Your thyroid gland is very sensitive, and its workings are influenced by various factors such as your adrenal health, gut health and nutritional status. How does it all fit in?

The fact is healthy thyroid function is not just about producing TSH, T3 and T4 in the correct amounts. T4 needs to be converted into T3, which is the active form of hormone used by your cells. In addition, T3 should be properly absorbed by the cells. These processes can be disrupted by stress, adrenal fatigue, leaky gut and nutritional deficiencies, leading to poor thyroid function and health. And there is a good chance that your doctor will not investigate these factors to determine your thyroid health or to find the real cause behind your hypothyroidism symptoms. Besides TSH, T3 and T4, there are other markers such as free T3 and reverse T3 that could provide some very useful insight into your thyroid health, or the lack of it. Unfortunately, these markers are usually overlooked and not included in the standard tests.

Did your doctor check your free T3 levels?


Your thyroid gland produces both T4 and T3 but not in equal amounts. About 90 percent of the hormone produced is T4, which is inactive. The body needs to convert this inactive T4 into active T3, which is what your cells need.

In the beginning, T3 is attached to thyroid binding globulin or TBG, a protein that carries the hormone in the bloodstream. T3 needs to be detached from TBG so that it can now bind to thyroid hormone receptors that are present in nearly every cell. This is free T3, which your cells need and use.

Is your T4 converting well to T3? 


T4 is converted into T3, the active form of thyroid hormone that your cells can utilize. Inadequate conversion of T4 to T3 could be one possible reason why you may not be responding well to prescribed medication. In such cases, a person would have normal TSH and T4 but still present symptoms of hypothyroidism.

Many factors can interfere with or negatively influence this critical conversion, such as:

  • Elevated cortisol: This can be caused by chronic inflammation and stress
  • Gut dysbiosis: Gut microbes produce deiodinase group of enzymes, responsible for converting T4 into T3. Poor gut health decreases the levels of healthy bacteria, supressing the conversion process.
  • Nutritional deficiencies: Minerals such as iron and selenium are required to activate enzymes required for T4 to T3 conversion. A shortage of these minerals adversely impacts the conversion. 
Estrogen dominance and poor liver health may also impact the conversion process. And there is something else that needs to be checked, but which is often overlooked during a standard thyroid test: your free T3 levels, which are bound to be low if T4 is not being converted to T3.

What about your TBG levels? 


Elevated TBG levels


As we mentioned above, T3 hormone cannot travel in the bloodstream on its own. It needs some help, which comes in the form of TBG. T3 binds to this transport protein to reach cells and tissues. At this stage, T3 is still inactive. It needs to be freed from TBG, which it does once it reaches the cells and binds to the receptors. So, what would elevated TBG levels indicate? This means your body has low levels of active or free T3, leading to hypothyroidism.

What can raise your TBG levels? This is mostly caused by estrogen dominance - high levels of the estrogen in the body. Progesterone production in women begins to decline after they reach their late 30’s. This leads to high levels of estrogen in women as they age. Prolonged use of birth control pills and hormone replacement therapy are the two other main causes of estrogen dominance.

It is also caused by stress, liver dysfunction, long-term exposure to chemicals commonly found in plastics, shampoos, creams and lotions. These chemicals, called xenoestrogens, disrupt the workings of endocrine glands and create hormonal imbalances. 

Reduced TBG levels


So, high levels of TBG cause less amounts of free or active thyroid hormone available to your cells. You can also have reduced TBG levels, with the resulting outcome of an upwards spike of free thyroid hormone levels. Too much hormone circulating in the bloodstream makes your cells resistant to its effect. This is very much like insulin resistance, where more than normal amounts of insulin in the bloodstream make your cells develop resistance.

With thyroid resistance, your cells can’t use the thyroid hormone despite its abundance.  So, you have the hormone, but it can’t enter your cells, again leading to symptoms that are typical of hypothyroidism. Low levels of TBG levels are caused by elevated testosterone, insulin resistance, sugar imbalances and polycystic ovarian syndrome (PCOS).

There could be another underlying issue with thyroid resistance: reduced activity of T3 receptors. As we know, T3 hormone binds to the receptors on the cells to gain entry. However, factors such as stress, increased cortisol levels and deficiency in nutrients such as zinc, vitamin A and fatty acids interfere with the proper functioning of T3 receptors. In addition, genetic mutations can also affect the function of these receptors. So, now you have the thyroid hormone, but the receptors are not working well enough to let the hormone in, leading to too much hormone in circulation. 

Could pituitary dysfunction or adrenal gland fatigue be the culprit?


The health of your adrenal glands is integral to your thyroid health. Long-term stress, chronic infections, metabolic disorders and sleep deprivation are some key factors that stress your adrenal glands, causing adrenal fatigue.

When you are stressed out, your adrenal glands produce more cortisol. Cortisol affects your thyroid function in many ways:

  • High stress and cortisol affect the pituitary gland, a gland that secretes TSH. With pituitary dysfunction, you won’t have sufficient amounts of TSH which is responsible for stimulating the thyroid gland to make T4 and T3.
  • Chronic stress and elevated cortisol impair the conversion of inactive T4 into active T3. This usually happens as during the time of stress; your body needs to slow down your metabolism and many other biological processes to heal and repair. 
  • Stress and cortisol also cause imbalances in sugar levels. Increased sugar levels affect your thyroid function.
  • Stress contributes to gut dysbiosis and leaky gut, which not only disturbs the conversion of T4 to T3, but also cause systemic inflammation, one of the risk factors for autoimmune disorder, such as Hashimoto’s.
  • Stress also raises estrogen levels and high estrogen increases the levels of protein called thyroid binding globulin (TBG). We have already discussed the role of TBG and how high levels of TBG cause thyroid trouble in the above section.
A recent 2018 study concluded that “PTSD was associated with higher risk of hypothyroidism in a dose-dependent fashion. Highlighted awareness for thyroid dysfunction may be especially important in women with PTSD.” [1]

Have you checked for reverse T3 levels?


There is another hormone your body makes. It is called reverse T3 (rT3). Some of the T4 that your thyroid gland produces is converted into rT3 by your liver. However, at times, your body makes more rT3 than normal. This usually happens when the body needs to conserve energy so that it can heal from stress or trauma. Chronic inflammation and infections, exposure to extreme temperature, emotional distress and celiac disease increase rT3 levels.

While your body is equipped to deal with small amounts of rT3, which it naturally makes, excessively high levels compete with T3 levels in their ability to bind with the thyroid hormone receptors. This eventually leads to reduced uptake of T3 by the cells, causing symptoms of hypothyroidism.

Do you have an autoimmune disorder?


Most of the cases of hypothyroidism are caused by Hashimoto’s. It is an autoimmune disorder where your immune system produces makes antibodies that attack and destroy your thyroid gland, damaging its ability to produce thyroid hormones. While genetics plays a key role in your susceptibility towards developing an autoimmune disorder, chronic inflammation, leaky gut, food allergies, infections and stress can also make you prone to developing autoimmunity.

On thyroid medication but still feel no better?


So, you are taking thyroid medication that increases your levels of thyroid hormone. But it is not making you feel any better. The question now is: what can sufficient amounts of thyroid hormone do when you are not able to convert T4 to T3? What if your cells have developed resistance to the thyroid hormone due to either low levels of TBG hormone or reduced activity of T3 receptors? In such cases, it doesn’t really matter if you are on thyroid hormone replacement therapy.

Not only does your body need to make thyroid hormones but it should be able to use them effectively. If not, you will continue to exhibit poor energy levels, weight gain, fatigue and an endless symptoms that are typical of hypothyroidism. And this could happen even if there is nothing indicated by your blood tests. And what happens when your test results show that your TSH, T3 and T4 are well within the “normal” range? Well, in all likelihood, your doctor would increase the dose of your medicine.
But that doesn’t solve the problem.

The problem is that most mainstream doctors don’t acknowledge the thyroid patterns we have discussed in this article. We are not denying the role of thyroid hormone replacement therapy. However, understanding the factors that disrupt your thyroid physiology and making efforts to address and eliminate these issues may help to improve your thyroid health and function.

Addressing your thyroid health is important


Thyroid disorder is not an isolated condition. It can increase your risk of other health problems. Individuals with thyroid dysfunction are at an increased risk of fibromyalgia, infertility, increased sugar levels and insulin resistance, heart disease, depression and many autoimmune disorders.

Ignoring your symptoms or continuing with your thyroid hormone medications despite any result will further deteriorate your health. What can you do?

  1. Eat healthy and exercise regularly
  2. Reduce inflammation
  3. Take care of your gut health and address leaky gut syndrome with the right diet and supplements
  4. Take steps to reduce stress
  5. Make sure you have a good nutritional status. Vitamins and minerals such as zinc, selenium [2], zinc [3], iron, magensium and Vitamin D [4] play very important role in keeping your thyroid health in good order.
  6. Suffering from any chronic infection? Don’t let it take root as infections stress your adrenals and cause inflammation.
  7. Keep your blood sugar levels in a normal range
  8. Identify your food allergies
  9. Sleep well
  10. Lose weight
All these interventions will not only improve parameters that are directly associated with your thyroid health but also work collaboratively to keep you in overall good shape.

References:
  1. Jung et al. Posttraumatic stress disorder and incidence of thyroid dysfunction in women. Psychological Medicine. 2018. 
  2. Ventura et al. Selenium and Thyroid Disease: From Pathophysiology to Treatment. Int J Endocrinol. 2017
  3. Betsy et al. Zinc Deficiency Associated with Hypothyroidism: An Overlooked Cause of Severe Alopecia. Int J Trichology. 2013
  4. Kim et al. Low vitamin D status is associated with hypothyroid Hashimoto's thyroiditis. Hormones (Athens). 2016