Desiccated Thyroid vs. Synthroid:
You’ve done everything right. You’re taking your Synthroid. Your doctor says your TSH looks great. But you still feel off.
You’re tired no matter how much you sleep. Your weight keeps climbing. You’re forgetful, flat, and anxious for no clear reason.
And when you bring it up, you’re told:
"It’s not your thyroid."
But maybe it is... Especially if you're only being treated with T4.
The Problem With T4-Only Treatment
Synthroid (levothyroxine) is the most commonly prescribed treatment for hypothyroidism. It’s synthetic T4—a storage hormone that your body must convert into T3, the active form.
In theory, this works. But in real life? Many women don’t convert T4 to T3 efficiently. And without enough T3, your cells aren’t getting what they need.
Symptoms like fatigue, weight gain, low mood, and brain fog persist—even when your labs are “in range.”
T3: The Active Thyroid Hormone That Actually Works
T3 is the hormone your body uses.
It powers your metabolism, brain, mood, menstrual cycle, and energy levels. It supports ovulation, regulates cholesterol, and stabilizes your nervous system.
If you’re low in T3, you’ll feel it—even with a normal TSH.
Research shows that low T3 is linked with poorer quality of life and a higher symptom burden in thyroid patients, even when TSH and Free T4 are normal
What Is Desiccated Thyroid
and Why Is It Different?
Desiccated thyroid extract (DTE) comes from porcine (pig) thyroid and contains a natural ratio of both T4 and T3.
It was widely used before Synthroid existed, but fell out of favor due to early concerns about consistency. Today’s formulas—like NP Thyroid, Armour, and ERFA—are standardized, tested, and regulated.
And many patients feel better on them.
What the Research Says About Desiccated Thyroid vs. Synthroid
A randomized trial published in The Journal of Clinical Endocrinology & Metabolism found that patients experienced better symptom relief and preferred desiccated thyroid over Synthroid. They also lost more weight without any changes in diet (PMID: 23454797).
Another study found that patients with low Free T3 but normal TSH improved significantly when T3 was added (PMID: 25333736).
Why You Might Need T3 Support
Wondering if desiccated thyroid or a T3 combo might be right for you? Here are some clues:
- You still feel unwell on Synthroid alone
- Your free T3 is low or reverse T3 is high
- You have Hashimoto's or Hypothyroidism
- You're struggling with brain fog, fatigue or depression
- You suddenly are experiencing stubborn weight gain
- You are being told you have high CHOLESTEROL
- You don't feel like yourself & know something else is going on!
These are signs that your cells may not be getting enough active thyroid hormone—even if your TSH is “normal.”
Final Thoughts: It’s Not All in Your Head
If you’re still symptomatic on Synthroid or levothyroxine, you’re not broken—and you’re not alone.
You deserve to feel well, not just “normal on paper.” For some, desiccated thyroid or a combination of T4 and T3 offers real, lasting relief.
There’s no one-size-fits-all thyroid protocol. But there is a way forward—with the right testing, the right support, and the right form of hormone therapy.
Looking for Thyroid Answers?
I offer virtual thyroid consultations across Ontario and have helped hundreds of women reclaim their energy, clarity, and cycles.
Not sure what tests go beyond TSH? I walk through the full thyroid panel in a past blog post.
DISCLAIMER: This is NOT a paid ad, promotion or affiliation with GI-MAP and Diagnostic Solutions. This test is strictly used in my practice due to its accuracy, clinical utility and thus ability to provide successful treatment to patients.
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If you are ready to dive deep into your gut health and clean up your hormones, apply to work with me!
Dr. Michele Webb
Your Hormone & Gut Health Naturopathic Doctor
