Updated: Natural thyroid vindicated!
Last week, in a fast-moving story, millions of hypothyroid patients reliant on medications like Armour Thyroid, Natural Desiccated Thyroid and Naturethroid were dismayed to learn of an impending FDA ban:
“FDA sent letters to manufacturers, importers and distributors of marketed unapproved animal-derived thyroid medications on Aug. 6, 2025. This letter notified them of the agency’s intent to take action against unapproved animal-derived thyroid medication. Doctors will be able to work with their patients to safely transition them to an FDA-approved [i.e. synthetic] thyroid hormone replacement medication. Manufacturers, importers and distributors of unapproved animal-derived thyroid medications may be subject to compliance action if they commercially distribute their unapproved products.
Additionally, these unapproved animal-derived thyroid medications are not eligible for compounding because these products are regulated as biological products under the Public Health Service Act.”
A Paul Revere Moment
It was a Paul Revere moment, and natural thyroid proponents like me bombarded social media with urgent appeals for patients and practitioners to tell legislators and regulators to rescind the looming crackdown.
Many were shocked to learn that the current MAHA-infused regime would issue such an edict. It turns out the regulatory action was merely a carryover from the Biden Administration. The proposed enforcement order was left like a ticking time bomb, only for newly-installed appointees to discover and defuse.
An FDA About-Face
NBC News reported that there was a rapid about-face from Marty Makary, the new FDA Commissioner, who reassured on “X”:
“FDA is committed to pursuing the first-ever approval of desiccated thyroid extract, pending results of the ongoing clinical trials. In the meantime, we will ensure access for all Americans.”
His boss at HHS, R. F. Kennedy Jr. lauded his decision:
“Love your approach of using gold standard science and common sense, @DrMarkaryFDA”
I’m relieved by their reconsideration and hope it will lead to rational and safe regulation of thyroid medications, and other natural products that support the health of Americans.
Natural thyroid formulations, long-disparaged by mainstream endocrinologists as outmoded “piggie-thyroid”, have been lifesavers for many of my patients whose symptoms were incompletely addressed by standard synthetic thyroid drugs like Synthroid.
To commemorate the reprieve, I reprise below in its entirety my 2020 article (“Natural thyroid vindicated!”) that sums up the advantages of natural thyroid:
As I Wrote in 2020 . . .
After over three decades of “breaking with the pack” and recommending natural thyroid to my patients, this fall ushers in a stunning vindication of this often-shunned practice.
In a study published in the September edition of Annals of Family Medicine, researchers compared synthetic thyroid medication (e.g. Synthroid, levo-thyroxine, Levothroid) to natural desiccated thyroid (e.g. Armour Thyroid, Naturethroid, NDT).
For background, the main knock against natural thyroid—frequently cited by conventional endocrinologists—is that it is “unreliable”, producing inconsistent dosing in recipients of thyroid replacement. This is said to be dangerous, especially for older patients. In fact, Medicare denies coverage for natural thyroid meds, leaving patients to foot the bill if they refuse to switch to reimbursed brands of synthetic thyroid.
Some doctors disparage natural thyroid as “piggie thyroid.” It’s considered old-fashioned, superseded by more efficient, modern formulations.
Natural Thyroid is Safe
This new study reveals that these knocks against natural thyroid are shibboleths; after three years of therapy with either of the two types of thyroid, TSH results were identical. Natural thyroid did not produce a higher rate of under or overdosing than did synthetic thyroid preparations.
TSH—thyroid stimulating hormone—is produced by the pituitary gland in response to circulating levels of thyroid hormone. When it’s high, it indicates not enough thyroid production (hypothyroidism) or replacement; when it’s low, it indicates over-production (hyperthyroidism) or over-replacement.
No One-Size-Fits-All
In response to the Annals study, the journal editors penned an editorial entitled “Returning to a Patient-Centered Approach in the Management of Hypothyroidism”. They note that the shift to synthetic thyroid medication, which occurred in the 70’s, thought to be more scientific, led to discouragement of the use of natural thyroid. “This one-size-fits-all approach,” they admit, “does not work for all patients. Emerging evidence shows that for many patients, symptoms persist despite normal TSH values.”
With surprising candor, the editorialists concede that this undermines patient confidence in their doctors. Patients are endlessly reassured that their tests are in normal range, but still feel unwell, and “reported feeling that their physicians were not willing to look further into why their symptoms were persisting.”
The result is that patients are left “feeling invalidated and without answers.” They’re sometimes persuaded that “it’s all in their heads” and end up with referrals to psychiatrists for unnecessary antidepressant treatment.
But there’s a reason that many patients don’t respond well to synthetic thyroid medication. A little basic physiology is in order here.
Explaining How Thyroid Works
The normal thyroid produces mostly T4 with only a little bit of T3. T4, which is inactive, is converted to T3 in the peripheral tissues. So the idea with synthetic T4 preparations is: why bother with T3 when you can just introduce T4, which will be converted to T3 wherever the body needs it?
Besides, endocrinologists claim, T4 has a nice, slow time-release effect, without the potentially hyper-caffeinating effects of rapid-acting T3. What could possibly go wrong?!
Turns out, a lot. Much recent research is demonstrating that many people—especially those with chronic medical conditions—have inefficient conversion of T4 to T3 in peripheral tissues. Environmental toxins and nutritional deficiencies may impair that bio-transformation.
So, when TSH levels appear “normal,” the brain, heart, muscles, skin and stubborn fat cells may not be getting optimal amounts of T3. Natural thyroid medications deliver a balanced blend of T4 and T3.
The solution is not to hew so slavishly to TSH levels, but rather to test for T3, free T3, and sometimes reverse T3 to get a better handle on thyroid status. Additionally, we doctors need to pay more attention to patients’ subjective experiences. The Annals article reassures us about the safety of natural thyroid alternatives, but doesn’t speak to its efficacy. Previous studies do.
Why is it That So Many Patients Prefer Natural Thyroid?
In a 2020 article entitled “Patient Experiences and Perceptions Associated with the Use of Desiccated Thyroid Extract” the researchers pose the question: “Why is it that so many patients prefer natural thyroid?”
58% of the patients surveyed cited “lack of improvement in hypothyroidism-related symptoms” as their rationale for switching; 22% had side effects with conventional thyroid meds.” Moreover, 81% of patients described natural thyroid as “moderately to majorly effective” and “more effective than previous therapy” (77%). The most frequently described benefits associated with natural thyroid were “an improvement in symptoms” (56%) and “a change in overall well-being” (34%).
The authors note: “Lack of individualized treatment and a feeling of not being listened to were recurrent themes” among people who eventually switched to natural thyroid.
And, in a landmark study in 2018, conventionally-treated hypothyroid patients had “a significant decrease in health-related quality-of-life and all domains (fatigue, vitality, cognition, anxiety, depressivity, emotional susceptibility, social life, daily life), as compared to controls.”
The researchers state: “Many patients (78.5%) reported having complaints despite taking thyroid medication and reported not feeling well (77.8%) while their blood values were within range.” Frequent complaints included fatigue, reduced daily functioning, coldness, muscle pain/cramps and being overweight.
When compared to users of synthetic thyroid medication, users of natural thyroid preparations had significantly higher quality-of-life scores.
Prescribing Natural Thyroid Can Be Tricky
Caution must be exercised with natural thyroid medications. They’re trickier to prescribe than synthetic thyroid. Some overzealous prescribers of natural thyroid dose their patients without regard to blood tests, relying instead entirely on patients’ subjective reports. Some individuals may get hooked on the stimulating effects of thyroid; others misuse it as a weight loss panacea.
Unfortunately, I’ve inherited some patients whose excessive use of thyroid medication for many years has damaged their hearts or thinned their bones. It’s sometimes harder for them to lose weight when their metabolisms down-regulate in response to too much over-activation. After gradual weaning, we’ve discovered that they were taking two or three times more thyroid than they needed. Finding a doctor who’s open to natural thyroid and is experienced in its application—but is a prudent prescriber—can be a challenge.
Resist Cookie-Cutter Medicine!
Hopefully, studies like these will jolt risk-averse health practitioners into taking less of a cookie-cutter approach to thyroid replacement. Natural thyroid medication has been a boon to countless patients that I’ve treated over the years. It would be a shame if unscientific bias were to deprive the millions of Americans with thyroid problems of more nuanced options tailored to their individual needs.
Stay tuned to Intelligent Medicine for timely updates on efforts to maintain access to natural thyroid and other treatments threatened by regulatory overreach!