Still Tired on Thyroid Medication? What Could Be Missing
Episode Summary
Med Matrix host Brian sits down with Dr. Sasha Rose, a licensed naturopathic doctor and acupuncturist with more than 20 years in functional medicine, to explain why so many patients are still tired on thyroid medication even when their TSH comes back normal. Dr. Rose walks through what standard T4 medications like levothyroxine actually do, why the conversion of T4 to active T3 so often gets missed, and how Hashimoto's, nutrient gaps, gut health, stress, sleep, and blood sugar all shape how someone feels. She contrasts conventional care, which usually stops at a single TSH test, with a functional approach that runs a fuller thyroid panel and looks at optimal rather than merely normal levels. The episode closes with what a personalized thyroid plan looks like at Med Matrix, from medication review and nutrient support to ongoing lab and symptom monitoring.
Why are you still tired on thyroid medication when your labs look normal?
Many patients come to Med Matrix already taking a thyroid medication, sometimes for years, and still feel exhausted, foggy, cold, or metabolically stuck. They are often told their TSH is normal, their dose is fine, and there is nothing else to do. On this episode of the Med Matrix podcast, host Brian sits down with Dr. Sasha Rose, a licensed naturopathic doctor and acupuncturist who has practiced functional medicine for more than 20 years, to explain what tends to get missed. As Dr. Rose puts it, a patient may be on the right medication, but it is most likely just one piece of the plan. Persistent fatigue usually means something else is going on.
What does thyroid medication actually do?
Dr. Rose explains that standard thyroid medications like levothyroxine and Synthroid are T4, the inactive form of thyroid hormone. The body has to absorb it, convert it, and use it in the form of T3, which is the active hormone that locks into the receptor and does the work. T4 is used because it has a longer half-life and circulates well. But if any step in that chain is impaired, from absorption to conversion, a person can keep taking their pill and still not feel well.
Why does the difference between normal and optimal matter?
TSH, or thyroid stimulating hormone, is usually the only marker that gets tested, and it is used to gauge dosing. The problem, Dr. Rose says, is that a normal result does not always explain how someone is functioning. The conventional reference range is wide, while functional medicine looks at a narrower, more optimal window and pairs it with symptoms, patterns, and trends. Top symptoms that can linger even with normal labs include fatigue, brain fog, weight gain, cold hands and feet, and hair loss, along with constipation, low mood, dry skin, and muscle aches.
How do Hashimoto's and T4 to T3 conversion fit in?
Hashimoto's, also called autoimmune thyroiditis, is the cause of the majority of hypothyroid cases, yet you cannot detect it from TSH alone. It requires testing thyroid antibodies, specifically thyroperoxidase and thyroglobulin antibodies, which insurance does not always cover. Dr. Rose also returns often to conversion. A specific enzyme removes one iodine molecule to turn T4 into active T3, and that step depends on nutrients like selenium, iron, zinc, iodine, and vitamin D. She compares it to baking: you can have the highest quality flour, but without the eggs, butter, and baking soda, you will not get good cookies.
What interferes with absorption, and why does gut health matter?
Because thyroid medication is taken orally, absorption is critical. Dr. Rose advises taking it at least 30 minutes away from food, and not alongside coffee, calcium, iron, fiber, or other medications. Taking it inconsistently, or having low stomach acid or gut inflammation, reduces how much is absorbed. Gut health matters for nutrients too. If the microbiome is off, even high quality supplements may not be absorbed, so addressing digestion is part of optimizing the thyroid.
Which labs help build a fuller picture?
Beyond TSH, Dr. Rose looks at free T4, free T3, thyroid antibodies, and reverse T3, which can crowd out active T3 at the receptor. She rounds out the picture with iron and ferritin, vitamin D, B12, and, when needed, zinc and selenium, plus inflammatory and blood sugar markers such as fasting glucose and hemoglobin A1C. Every panel is personalized rather than identical for each patient, so some markers are ordered and others left out depending on the person.
What does a personalized thyroid plan look like at Med Matrix?
Care begins with a full health history, a symptom timeline, and a comprehensive new-patient panel, not just a thyroid test. A personalized thyroid plan may include a medication review, nutrient optimization, protein and blood sugar support, gut support, and work on stress, sleep, and inflammation. Med Matrix also uses an InBody scan to see whether a change in weight is fat, muscle, or water. Dr. Rose monitors both labs and symptoms over time, noting that she does not like to chase lab values but does not ignore them either. To start, you can book a discovery call through the Med Matrix website.
Key Moments
Key Topics
- 1
Why a normal TSH does not always mean you feel normal
- 2
What thyroid medication does and where the process can break down
- 3
The difference between inactive T4 and active T3
- 4
Why T4 to T3 conversion so often gets missed
- 5
Hashimoto's and testing thyroid antibodies (thyroperoxidase and thyroglobulin)
- 6
Reverse T3 and how it can block active thyroid hormone at the receptor
- 7
Symptoms that persist even with normal labs: fatigue, brain fog, weight gain, cold hands and feet, hair loss
- 8
How to take thyroid medication so it absorbs properly
- 9
Nutrients that support conversion and energy: iron, selenium, zinc, iodine, vitamin D
- 10
Why gut health affects both medication and nutrient absorption
- 11
Normal versus optimal reference ranges in functional medicine
- 12
What a personalized thyroid support plan at Med Matrix includes
Quotable Moments
“They might be on the right medication, but it's most likely just one piece of the plan.”
“We are not the same biochemically and you can't just throw the same dose at every single person and expect the same result.”
“I really don't like to chase lab values, but I also don't ignore them.”
“You might have like the highest quality flour in the world, but if you don't have the baking soda and the eggs and the butter, you're not going to end up with very good cookies.”
“A normal does not always explain how they're functioning.”
Treatments Mentioned
FAQ
Thyroid FAQ
A normal TSH does not always reflect how you actually feel. Dr. Rose explains that TSH is often the only marker tested, yet fatigue can persist because of poor medication absorption, impaired T4 to T3 conversion, Hashimoto's, nutrient gaps, gut issues, stress, sleep, or blood sugar. The medication may be right, but it is usually just one piece of the plan.
Standard medications like levothyroxine and Synthroid are T4, the inactive form of thyroid hormone. The body has to absorb it and convert it into T3, the active hormone that locks into the receptor and does the work. If that conversion is impaired, you can have plenty of inactive T4 circulating without getting the final active product, which can leave you symptomatic.
Hashimoto's, also called autoimmune thyroiditis, is the cause of the majority of hypothyroid cases. You cannot detect it from TSH or free T4 alone. It requires testing thyroid antibodies, specifically thyroperoxidase and thyroglobulin antibodies, which are not always covered by insurance and so often get skipped in conventional care.
Dr. Rose recommends taking it at least 30 minutes away from any food, and not alongside coffee, calcium, iron, fiber, or other medications and supplements. Taking it consistently at the same time each day matters too, and gut issues like low stomach acid or intestinal inflammation can reduce how much is absorbed.
Iron, selenium, zinc, iodine, and vitamin D are important for converting T4 into active T3 and for energy. Dr. Rose notes vitamin D deficiency is especially common where we live. Testing levels, including ferritin for iron stores, helps guide support with real data instead of randomly throwing supplements at the problem.
Beyond TSH, a fuller picture includes free T4, free T3, thyroid antibodies, and reverse T3, which can crowd out active T3 at the receptor. Dr. Rose rounds this out with iron and ferritin, vitamin D, B12, and sometimes zinc and selenium, plus inflammatory and blood sugar markers such as fasting glucose and hemoglobin A1C.
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Thyroid and Adrenal Fatigue Treatment
Thyroid specialist in South Portland, ME running a full panel: free T3, reverse T3, and Hashimoto's antibodies, not just TSH. Adrenal fatigue treatment too.
