Dr. Michael E. Doyle: Conventional and Alternative Medicine

Myth #1: The TSH (Thyroid Stimulating Hormone) blood test is the only way to diagnose hypothyroidism/low thyroid.

Facts: First, there is no perfect test in medicine—not the TSH or any other. Second, nearly a century before the TSH test was developed, doctors made the diagnosis of hypothyroidism without any tests at all. They listened to their patients and examined them. Since then, there have been many tests that have been blindly followed until they proved to be unreliable and were discarded.

To this day, there are at least three types of hypothyroidism for which the TSH test does not even test. The TSH is not a useful test for hypothyroidism caused by dysfunction of the pituitary gland or of the hypothalamus (part of the brain,) or for hypothyroidism caused by “tissue resistance” to the effects of thyroid hormone.

My conclusion: The TSH test can miss the diagnosis of hypothyroidism. To most accurately identify hypothyroidism, I start with the approach that has worked for over a century. I listen to the patient and look for evidence of low thyroid function. If the patient appears hypothyroid, I order blood tests including the TSH, but I also (1) check basal body temperature,¹ and (2) check the urine thyroid hormone levels.² I then interpret all test results in the context of the individual patient.

Myth #2: Normalizing the TSH (Thyroid Stimulating Hormone) blood test is the best way to treat hypothyroidism.

Fact:Many studies have shown adjusting thyroid doses to normalize the TSH blood test leaves many patients with symptoms of low thyroid. World-renowned thyroid specialist, Sir Anthony Toft, MD, discussed this sad fact in 2002. In a speech to the British Endocrine Society, Dr. Toft reviewed some of the evidence that demonstrated that the modern TSH-centered approach was ineffective. He concluded, “…the treatment of hypothyroidism is about to come full circle”—going back to the approach that worked so well before all of our modern tests and treatments were invented.³

My conclusion: Using the patient as my guide, I focus on reversing the signs and symptoms of low thyroid function while avoiding side effects or signs of thyroid excess. When the TSH is normal but the patient continues to be symptomatic, I prefer to err on the side of treating the patient—not normalizing the blood test.

Myth #3: Thyroid treatment that reduces the TSH to below the normal range (TSH suppression) has been shown to be harmful, causing atrial fibrillation (a heart rhythm abnormality) and bone thinning.

Facts: When thyroid hormone is given to a patient, TSH levels decrease. Some say that thyroid treatment that reduces the TSH to below the normal range causes bone thinning and atrial fibrillation.

Before the TSH test was invented, generations of patients flourished on doses of thyroid medicine that routinely suppress the TSH. To this day, patients with thyroid cancer who are given doses to intentionally suppress the TSH, do very well on this regimen. In 2004, after review of the scientific literature, the US Preventive Services Task Force—a leading authority—addressed the question and concluded that despite the multitude of studies, there remains no proof that TSH suppression is dangerous.⁴

My conclusions: Listen to the patient, examine the patient and adjust treatment until the patient is well. A century of medical experience and scientific evidence indicate that giving a patient enough thyroid hormone to make them well is a reasonable and safe approach. Blood tests, urine tests and tracking body temperatures all provide additional information, but no one test should be blindly followed.

Myth #4: Natural thyroid extracts are dangerous because they are not regulated and not consistent in dose.

Fact: Natural thyroid extracts such as Armour Thyroid are FDA approved prescription medications that contain all 4 human thyroid hormones (T1, T2, T3 and T4.) They are prepared in accordance with the U.S. Pharmacopeia.⁵ Synthetic thyroid extracts, such as levothyroxine contain only T4 and are also FDA approved.

Ironically, synthetic T4 preparations seem to have had many more problems with dose consistency than has Armour Thyroid. FDA records show repeated problems with potency and consistency for T4 products including Synthroid.^6,7

My conclusion: There is no evidence that natural thyroid extracts such as Armour Thyroid are unsafe or any more dangerous than synthetic thyroid treatments. In fact, my experience is that natural thyroid extracts are much more effective at restoring normal metabolism and, therefore, very likely better for one’s health.

Myth # 5: Once you start thyroid hormone, you need to take it for the rest of your life.

Fact: Taking thyroid hormone will not permanently shut down the thyroid gland.⁸

My conclusion: Be aware that suppression of thyroid function—which can occur during treatment—is only temporary and will not create a permanent dependency.

Thyroid References

1. JAMA August 1, 1942, vol. 119, pp1072-1074.
2. Basier, W.V., Hertoghe, J., and Eeckhaut, W.: Journal of Nutritional and Environmental Medicine (2000) 10. 105-113.
3. http://www.endocrine-abstracts.org/ea/0003/ea0003s40.htm
4. Ann Intern Med 2004; 140: 125-7.
5. http://www.armourthyroid.com
6. http://www.brodabarnes.org/fda_notice.htm
7. http://www.thyroid-info.com/articles/synthroidproblems.htm
8. N Engl J Med. 1975 Oct2;293(14):681-4.