hypothyroid, thyroid disease, thyroid health, thyroid labs, lab results

Why Your Lab Results Look Normal but You’re Still Hypothyroidal


Have you been told that your thyroid lab results look normal, yet you still have symptoms of hypothyroidism like fatigue, digestive issues, depression, unexplained weight gain, loss of hair, cold hands & feet, etc.?  Do you have a feeling that something is being missed or overlooked?  Well, you’re probably right, and definitely not alone.

Just moments ago, I ended a call with a client who mentioned she had doctors that would only run the marker for TSH because that’s the “truest indication of thyroid function.” Unfortunately, that’s completely false. In fact, other markers that most practitioners run, like Free T4 & Free T3 only paint a partial picture of your thyroid status.

There are several enzymes that need to be considered when assessing thyroid function. Deiodinase enzymes are present in different tissues of the body, and each have different functional effects throughout the body.

What are Deiodinase Enzymes?

Deiodinase Type I (D1) helps convert T4 to the active T3 throughout the tissues of the body, yet it has no effect on pituitary function, or TSH production. During times of physiological, emotional and biochemical stress, D1 is suppressed, causing a decrease in T4 to T3 conversion throughout the body’s tissue. The result is an increase in symptoms of depression, fatigue/CFS, weight gain, fibromyalgia and blood sugar imbalances.

Women already have lower D1 levels than men, making them more prone to hypothyroidism of the tissue, regardless of “normal” TSH levels.

Deiodinase Type II (D2) is only found in the pituitary gland.  It also helps to convert T4 to T3, but is 1,000 times more efficient than D1, yet is much less sensitive to biochemical factors like toxins and medications. Whereas D1 suppresses T4 to T3 conversion during times of physiological, emotional & biochemical stress, D2 has the opposite reaction.  When stress is introduced, D2 will up-regulate and increase T4 to T3 conversion within the pituitary gland, but not throughout the rest of the body.  

Because the pituitary levels of the thyroid hormones are controlled differently than those hormones in the bodily tissue, pituitary T3 levels will typically be significantly higher than levels elsewhere.  The two reasons above are why TSH is not always the best indicator of thyroid status.  With an elevated TSH, you can be almost certain that your body is deficient in T3, however, with a “normal” TSH, there’s a chance you’re still deficient in T3, or hypothyroidal.

Deiodinase Type III (D3) is contained in all tissue except for the pituitary, and has a completely different action.  Instead of converting T4 to T3, D3 converts T4 to reverse T3 (rT3).  rT3 blocks T3 from binding to its receptor sites, thus inhibits the effect of T3, but also suppresses D1, reducing overall T4 to the active T3 conversion, leading to a reduced metabolism and a hypothyroid state.

This is yet another reason why your doctor may assess your thyroid function as normal, yet you still suffer from fatigue, depression, weight gain and other hypothyroid symptoms.

A Vicious Cycle

This whole state of hypothyroid ends up being a vicious cycle. We already discussed how stress affects D1 & D2, leading to reduced tissue thyroid levels.  Stress also causes an increase in cortisol.  Elevated cortisol production creates a disconnect between TSH and cellular T3 levels, causing a decrease in T3 and an increase in rT3.

Stress not only can directly impair T3 levels, but also further impairs T3 levels due to the increase in cortisol, leading to symptoms like weight gain.  So then you start “dieting”.  Dieting (reduced caloric intake) can result in reduced cellular T3 levels, causing a reduction in metabolism.

In essence, dieting can cause your body to go into starvation mode, and can stay there for years, making it extremely difficult to lose weight.

We’ve learned for decades that, along with dieting, we need to exercise intensely in order to reduce our body weight.  Yet, studies show that intense exercise reduces T4 to T3 conversion and increases rT3.  This mechanism counters what are thought to be “positive effects” of exercise.  Combine that with intense dieting and the effects are compounded.

“Diet & Exercise”, right?  Nope…

Then we also have chronic pain, another symptom of hypothyroid, which can further suppress D1 and increase D2. The effects? Causing a further reduction in cellular T3, regardless of the TSH reading. So as I’ve said there are reasons why TSH is not always the best indicator of thyroid status.

What To Do

First and foremost, if you feel you’re suffering from hypothyroid, but your practitioner tells you your thyroid is “normal”, get a second, or third opinion.  Work with a practitioner that understands all the mechanisms that can affect tissue thyroid levels.

In the meantime try these tips below to get started:

  1. Reduce as much stress as possible, physical, mental & environmental.
  2. Switch to natural household products and cosmetics, as the chemical toxins will decrease D1 & increase D2, affecting your tissue T3 levels and their ability to uptake the hormone.
  3. Have a positive mindset.  Express thanks & gratitude.  
  4. Meditate and/or pray.  
  5. Surround yourself with positive thinking people.  Toxic thoughts create a toxic body.
  6. Stop dieting and over-exercising.  
  7. Eat healthy food, like fresh, organic meats, fish & veggies, but don’t over-focus on calories.  If you struggle with healthy food preparation, find a healthy meal recipe book.
  8. Perform moderate exercise at most.

In the upcoming weeks as we have some of our original e3 Energy Evolved recipes brewing for fall for natural thyroid, autoimmune, and metabolism restoration that we’ll be sharing with our online e-newsletter community, AND within the next few months our new e3 Eats Cookbook will be released!

Join our e-newsletter to be a part of it with us.

Damian Dubé

Functional Medicine & Functional Nutrition Practitioner at e3 Energy Evolved
Damian Dubé, BS, FMP, CNC, FDN-P, CES, CPT is a Functional Medicine Practitioner, Certified Nutritional Consultant, Functional Diagnostic Nutrition Practitioner, Corrective Exercise Specialist, Certified Personal Trainer, NPC Bodybuilding Athlete & Expert Magazine Writer with 30 years of experience.
Damian Dubé

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