Thyroid Thursday Episode 63:
Why You Can’t Trust TSH and T4 If You Have Hypothyroid Symptoms!
Hey everybody, it’s Dr Eric Balcavage. We’re back for another edition of Thyroid Thursday. Today I want to talk about why you can’t trust TSH and T4 if you still have hypothyroid symptoms. You know, whether you’ve been diagnosed with hypothyroidism and you’re on the Synthroid, Levothyroxine or a T4/T3 combo, if you’ve been told you don’t have a hypothyroid condition because your TSH and T4 is normal, if you have hypothyroid symptoms; you cannot necessarily trust TSH and T4 as values of normal thyroid physiology.
There’s a great paper from 2013 by Dr Bianco, Cracking the Code for Thyroid Hormone Signaling. In that paper he has a great quote, and it says, “cells are not innocent bystanders in the process of hormone signaling”. Meaning that just because the gland produces enough T4 and T3, and just because the plasma levels of T4, T3, and TSH are normal, doesn’t mean that T4 is going to get into the cell and convert from T4 into T3 and stimulate your metabolism. The cells really determine what happens to the T4 and T3. Adequate T4 in the plasma does not necessarily ensure T4 conversion to T3 within peripheral cells.
That’s a key thing to understand.
The reason you have hypothyroid symptoms is because you have insufficient T3 in your peripheral cells. That’s why you have hypothyroid symptoms. It doesn’t matter what TSH, T4, or T3 are in your plasma, it matters how much T4 to T3 conversion is occurring inside most of your cells and how much of that T3 is getting to the nucleus and actually stimulating metabolism. If you have hypothyroid symptoms, that is not happening adequately, it doesn’t matter what TSH and T4 are.
There are enzymes inside your cells called deiodinases, that determine whether you increase T4 conversion to T3, or decrease conversion of T4 to T3. Typically when you’re decreasing conversion, T4 is being converted to something called reverse T3. That test is rarely ever run in the conventional medicine model because most doctors don’t really care what it’s value is. They’re not concerned about it. It doesn’t change their treatment considerations when it comes to prescribing thyroid hormone.
A TSH value is representative of pituitary saturation and thyroid gland function in homeostasis. So what does that mean? That means that when a person has no stress on the system, they’re in balance, in harmony, and they’re functioning really well; that’s homeostasis. Most of the people who have hypothyroid symptoms aren’t in homeostasis.
If you’re in homeostasis, yes, you can use TSH as an indicator of gland disease. But, if you’re not in homeostasis, your under physical stress, chemical stress, emotional stress, or microbial stress, any of these types of stressors, they can change what happens at the cellular level. They can change what happens with thyroid physiology overall. The gland can function well, but you can have hypothyroid symptoms regardless of what’s happening at the gland. The gland can be perfectly healthy and you can have hypothyroid symptoms. When you’re not in homeostasis and you are in a stressed state, the body goes from a thyroid homeostatic state to a thyroid allostatic state where it changes thyroid values and thyroid hormone levels (TSH, T4, T3, free T4, free T3, reverse T3), based on the stress coming onto the body and onto the cells.
Another reason why TSH isn’t necessarily valid is that the pituitary gland is much more sensitive to small changes or fluctuations in T4 values. The pituitary and what we call the central thyroid regulatory system (the hypothalamus, the pituitary, the thyroid gland), is much more sensitive to small increases or decreases in T4. Now, one of the reasons is that the pituitary gland can only make T4 into T3. It does not have deiodinases that can convert T4 into inactive forms. The central system, essentially the brain, is much more sensitive to small fluctuations. So a little bit of thyroid hormone can put the brain back into normal thyroid physiology, but not be enough or supportive of the peripheral tissues.
In strained states (which is what most people are in when they come to see us, they’ve got issues that are causing them to be symptomatic and they’re not well), TSH is no longer a valid marker of thyroid physiology. If you’re tired, fatigued, having hypothyroid symptoms, have emotional stress going on in your life, maybe you’ve got chronic GI issues going on, TSH is no longer a valid marker. Another thing to consider is that inflammatory chemicals can suppress the pituitary gland and suppress TSH. TSH can look normal because the pituitary is saturated, or TSH could look normal because inflammation is suppressing the pituitary’s ability to make TSH.
So what can you do?
First, you always want to demand a comprehensive thyroid panel. It’s more than TSH and T4. It’s TSH, T4, T3, free T4, free T3, reverse T3, T3 uptake and thyroid antibodies.
Second, and even better, is demand a comprehensive metabolic panel that looks for inflammatory markers like CRP, homocysteine, uric acid, and insulin levels. Inflammation changes your deiodinase activity to down-regulate cell metabolism and convert T4 to reverse T3. You need to take a look more comprehensively. Not just at the thyroid gland, but all of the chemistry in the body.
The third thing you’re probably going to have to do, is to find a functional medicine practitioner like myself. The medical doctors and endocrinologists have been working with the same model that it’s all about the gland. As long as the gland makes sufficient T4 and T3, based on a TSH and T4 value in the blood, then everything else in thyroid physiology works. Unfortunately, that is just not the case. Today’s research shows that thyroid physiology is more than the gland. It really comes down to what’s happening at the cellular level, primarily because that’s what induces the hypothyroid symptoms.
So hopefully that helped you today. If you have questions, put them below wherever you watched this video. Look forward to another Thyroid Thursday in the coming weeks. Take care.
Dr Eric Balcavage
Chronic Condition Recovery Center
www.chronicconditionrecoverycenter.com
610-558-8920
References:
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3715916/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1578599/
- https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5517413/
