There is no doubt there is an epidemic of thyroid disorders right now and they are on the rise. It seems that the greater majority of women have some degree of thyroid dysfunction. Unfortunately, medical doctors do not look for the cause of hypo or hyperthyroidism and usually prescribe a medication which masks the actual cause of the actual thyroid issue leading to a worsening of symptoms over time.

Women come to my office with thyroid symptoms, but their doctors claim that it is normal based on the blood tests. Usually, they check the level of TSH and if it is within the range they do not look further. Unfortunately, the TSH level is only a small piece of the puzzle. We need to assess multiple parameters to fully evaluate the function of the thyroid.

As an alternative medicine doctor, one pattern that I have seen several times over the years is normal TSH, normal T4, but low T3 hormone.

Let’s go over some basics about the thyroid and its hormones.

Thyroid Basics

The thyroid and other glands all work together to regulate a variety of hormones in the body. Let’s see how the body properly maintains the thyroid function.

The hypothalamus, which is in the brain, monitors the levels of thyroid hormone in the body and produces thyrotropin-releasing hormone (TRH).

Then, this TRH hormone talks to the pituitary to produce thyrotropin also known as TSH (thyroid stimulating hormone).

This TSH acts on the thyroid gland, which makes thyroxine (T4) and triiodothyronine (T3), the main circulating thyroid hormones.

The thyroid makes more T4 than T3. Indeed, 93% of the hormone produced by the thyroid gland is T4.

Free T3 (FT3) is approximately five times more biologically active than T4, meaning that T3 performs the great majority of the thyroid functions.

The critical step for a healthy thyroid is the conversion of T4 to T3 by the enzymes called deiodinase which there are 3 different types (D1, D2, D3). This conversion occurs in multiple organs, such as in the liver, gut, skeletal muscle, brain, and the thyroid gland itself.

But in some cases, the body conserves energy by converting the T4 instead into Reverse T3 (RT3), an inactive form of T3 that is incapable of delivering oxygen and energy to the cells, as T3 does. Importantly, the enzyme D3 transforms T3 into an inactive form of the thyroid hormone in the liver in order to maintain a proper amount circulating in the blood: too much or too little of this hormone is problematic.

These hormones are carried in the blood by transporters produced by the liver called thyroid-binding globulin (TBG). TBG is responsible for carrying T3 and T4 to all the tissues and organs of the body so that they can perform their biological functions. Thyroid hormones by TBG are rendered inactive.

As we can see, there is a complex interplay involving several organs and components to maintain a healthy thyroid. Now that we know more about this, let’s go over some factors that affect the balance of T3 in the blood and body.

1. Adrenal fatigue

It is well-known that stress affects the function of both the adrenals and the thyroid. Prolonged exposure to stress will eventually cause the over-production of cortisol, which increases inflammation in the body – among other complications. Increased blood cortisol inhibits or alters the production of active thyroid hormone T3. If blood levels of cortisol and other stress hormones are high for a prolonged period of time, the conversion of T4 to T3 is significantly reduced. In addition, the body converts more of our T3 into RT3 rather than FT3. This imbalance essentially works to put the “brakes” on all of your metabolic processes, slowing them down and causing hypothyroid symptoms, such as low energy, weight gain, hormonal imbalances, etc.

2. Oestrogen dominance

We previously stated that elevated cortisol negatively impacts the thyroid function by decreasing the conversion of T4 to T3.

Another side effect of high-stress hormones is that it can lead to an accumulation of oestrogen in the body, resulting in a high ratio of oestrogen/progesterone. Interestingly, this extra oestrogen dramatically augments the circulating level of TBG. As we saw above, thyroid hormones bound by TBG are inactive, meaning they cannot perform their biological functions. T4 can’t be converted to T3 and T3 can’t be converted to Free T3.

The liver plays a critical role in the proper regulation of circulating blood hormones. The phase 1 and 2 pathways of detoxification play an important role in eliminating the excess of oestrogen in the body.

Through these pathways, the liver converts excess oestrogen into compounds that can be excreted by the body through the normal channel of elimination. The liver does it efficiently as long as we do not overload it with harmful chemicals, metals, prescription drugs, alcohol, and so on, which is the norm today. In other words, the liver acts as a hormone processor, manufacturer, and regulator. But when the body experiences a hormone excess, the liver is not able to process this excess of hormones as quickly, causing a hormone imbalance.

You can promote your liver to function better by eating a lot of protein. The 2 phases of detox require lots of protein in order to properly remove toxins out of the body. Vegetables of the cruciferous family are also a key player in assisting this function of the liver.

Finally, weight gain is another factor to consider. An excess of 10 lbs. or more leads to a sluggish liver (non-alcoholic fatty liver). This overload of fat interferes with the suitable elimination of toxic compounds.

3. Low Progesterone

By reviewing laboratory results, we oftentimes see that T3 and T4 are normal and that the TSH is slightly elevated. Usually, medical doctors would diagnose the patient with hypothyroidism based on symptoms such as fatigue, intolerance to cold or thinning of the hair and give them medication to help the thyroid. But usually other symptoms like weight gain, water retention, headaches, low sex drive, and PMS do not improve by taking a thyroid medication.

We see this pattern every day in our office and it is associated with oestrogen dominance, meaning an excess of oestrogen circulating in the body. When this imbalance is being treated, either by stimulating the removal of excess oestrogen or by correcting the low production of progesterone or both, all these hypothyroidism symptoms disappear and so does their presumed hypothyroidism.

Interestingly, rebalancing the pestrogen/progesterone ratio is also greatly beneficial for women with Hashimoto’s disease. Hashimoto’s is an autoimmune inflammatory process of the thyroid gland. Basically, for a reason that is not well understood (even though some doctors think that a virus might be a trigger), the body starts producing antibodies against the thyroid. Those antibodies bind to the TSH receptors, displacing the hormone TSH, and prevent it from performing its proper function. As this situation progresses, the cells of the thyroid are being destroyed and inflammation occurs.

The immune system is not perfect and that is why there are several quality control processes to ensure that it does not go awry and start making antibodies that could potentially attack every cell of our organs/tissues. One such mechanism is the production of corticosteroids (for instance, cortisol, among others). These hormones block this attack by our own antibodies against our own tissues.

It is now believed that oestrogen plays an important role in regulating corticosteroid blood level. Indeed, oestrogen dominance significantly reduces the production of corticosteroid by the adrenals. In other words, corticosteroids have a suppressive regulatory function of the immune system and oestrogen inhibits this, leading to the development of a variety of autoimmune conditions. Progesterone is also necessary for the adrenals to make corticosteroids. Therefore, restoring the proper level of progesterone enhances normal corticosteroid production, thus suppressing the autoimmune attack and Hashimoto’s.