Doctors Explain Why the Most Common Thyroid Test Misdiagnoses Some Patients
The thyroid gland regulates many bodily functions, playing a key role in metabolism, growth, hormones, immunity, detoxification, and so much more.
Located in front of the neck just below the Adam’s apple, the thyroid is so critical to our health that when it’s compromised many different symptoms can result, such as obesity, low energy, hypertension, hair loss, difficulty concentrating, frequent infections, and constipation just to name a few.
Data from the National Health and Nutrition Examination Survey suggests that about 1 in 300 Americans suffers from a low functioning thyroid, known as hypothyroidism. But some doctors believe the actual number is much higher.
One such physician is Dr. Raphael Kellman, an integrative medicine practitioner in New York City who specializes in thyroid disorders. Kellman said we’re in the middle of a “thyroid epidemic,” but that routine blood tests fail to see it.
“One of the reasons why the extent of the epidemic is not being appreciated is because the routine tests do pick up a lot of people, but it’s also missing a significant number,” he said.
A Misleading Test
To diagnose a thyroid disorder, doctors primarily look to a pea-sized gland in the brain—the pituitary—for answers. The gold standard to determine thyroid problems is a blood test to measure how much thyroid stimulating hormone (TSH) the pituitary gland excretes into the bloodstream.
Think of TSH as a message of encouragement. When the thyroid isn’t producing enough hormones, the pituitary sends TSH in hopes of kicking the thyroid into gear. A TSH level that is higher than normal indicates that the thyroid is failing to respond to the pituitary’s message because it is too weak to meet the body’s needs. A TSH test verifies the problem, thyroid hormones are prescribed to compensate for the underproductive gland, and TSH drops to a normal range because the pituitary is satisfied with hormone levels.
That’s how it’s supposed to work anyway. But Kellman said there are many patients who exhibit several classic symptoms of a low thyroid, but may still show a normal TSH level. He said the TSH test is “terribly misleading” because it frequently misrepresents what is happening in the thyroid and the pituitary.
“That’s why there are an untold number of people walking around with unexplained fatigue, unexplained brain fog, and difficulty losing weight even though they’re following a good diet. These people sense intuitively that there is something wrong with their thyroid, but it’s not being picked up. That’s why they go from doctor to doctor sometimes for years.”
Most diagnosed cases of hypothyroidism in the United States are due to an autoimmune disorder called Hashiomoto’s thyroiditis—a condition in which the immune system actually attacks the thyroid gland. But Kellman suggests that there are other causes of hypothyroidism that do not exhibit the elevated TSH levels doctors are looking for.
“It’s not just Hashiomoto’s that’s causing hypothyroidism,” Kellman said. “Many of our diseases, including thyroid disease, are due to environmental toxicity—a subject that very few are fully aware of, and they’re even less aware of how it may be affecting the thyroid system.”
Kellman points to environmental chemicals known as “endocrine disruptors” for the cause of untold numbers of thyroid problems.
Endocrine disruptors mimic hormones including thyroid hormones, according to the National Institute of Environmental Health Science. They also harm the immune and reproductive systems, and adversely affect development in children. Sources of these chemicals include household items such as plastic bottles, metal food cans, detergent, flame retardants, children’s toys, cosmetics, and pesticides.
Kellman said it only takes a tiny amount of these common chemicals to upset the system.
“Toxins don’t have to reach high levels in order to affect a delicate system that’s very, very vulnerable to toxicity,” he said. “Especially the thyroid, which I think is the most vulnerable component of the endocrine system.”
The notion of a chemical that interferes directly with the endocrine system is a fairly new concept. In conventional toxicology, toxicity is a clear line: a chemical is poison when exposure is over the dose threshold, but minimal exposure is considered safe. The endocrine disruptor concept blurs the toxicity line, as doctors and scientists said that what we once thought were safe levels of exposure may in fact be inflicting significant damage.
According to a statement from the Endocrine Society, there is strong evidence for adverse reproductive outcomes (infertility, cancers, malformations) from exposure to endocrine disrupting chemicals. There is also a growing body of evidence for effects on other endocrine system concerns, including metabolism, insulin and glucose homeostasis, and thyroid problems.
The molecules of endocrine disrupting chemicals have very similar properties and shapes to our own hormones. They fit snugly into the hormonal receptors in our cells, upsetting the delicate dance of hormonal production and signaling throughout the system.
Dioxins and PCBs are the best documented endocrine disrupting chemicals, but thousands more are suspect. Mercury, lead, phthalates, and BPA are considered some of the worst offenders.
Most accept the endocrine disruptor premise—it’s the scope of the problem that’s the point of debate. Environmentalists said there are many more endocrine disrupting chemicals in our world than industry will acknowledge. A system of regulatory oversight for limiting exposure of such chemicals to prevent illness is still in the works.
We all come in contact with these chemicals every day, but the most vulnerable among us—such as children and the elderly—are especially susceptible to their influence.
“Women are more vulnerable too,” Kellman said. “Because of their cycle, their hormones are always changing and they’re more susceptible to issues of timing. If those endocrine disruptors affect them at specific times they’re more likely to experience the adverse effects.”
Bringing Back a Better Test
In order to detect a thyroid problem, a TSH test must assume that hormonal signaling in the rest of the system is functioning normally. According to Kellman, because endocrine disrupting chemicals may disrupt many points along the signaling system and not just the thyroid, it can be difficult to identify an imbalance with a TSH test alone.
Kellman said this is a big reason why the conventional blood tests and reference ranges used to detect a thyroid abnormality can overlook real problems.
“We have to realize that when it comes to endocrine disruptors the blood test can be elusive. It doesn’t show up as definitively as when you see the effects of the autoimmune process,” he said. “It may not be as evident on blood testing. And blood tests can even look contradictory.”
For patients who experience symptoms associated with hypothyroidism but who have normal TSH results, Kellman calls for a thyrotropin releasing hormone (TRH) stimulation test. TRH tests were once widely used to detect thyroid disorders until the TSH test came on the scene. But Kellman points to research, which suggests that a return to TRH testing may provide doctors with a better picture for some patients.
“In 2007, there were two studies that came to the same conclusion I came to, which is that this test is very important for a lot of people,” Kellman said. “It should be brought back into practice when routine tests don’t have an explanation for the patient’s symptoms.”
The test involves an injection of thyrotropin, a compound produced by the hypothalamus gland. When met with a flood of thyrotropin, the pituitary gland releases its entire store of TSH.
The TRH test shows what is actually inside the pituitary and not just what the gland releases into the blood stream at a particular moment in time. Patients who show normal levels in conventional tests, may actually have a ton TSH stored in the pituitary indicating a real problem.
“I find that by using this test, we’re in a much better position to see the full extent of the full epidemic,” Kellman said.
Dr. Annette Schippel, a chiropractic physician specializing in functional endocrinology, agrees that the conventional blood test is limited. But she said that the prevailing symptoms of obesity and fatigue are actually rooted deeper in the endocrine system—the adrenal glands.
“What I think is going on is that people exhibit the symptoms while thyroid values are still normal because it’s not primarily their thyroid. I think its starts with the adrenal. It’s the adrenal issue that makes people tired, affects their metabolism, their weight management, it even affects the hair loss. With these symptoms, thyroid and adrenals go hand in hand,” she said.
According to Schippel, the thyroid gets weak because it’s compensating for weaker adrenals. She illustrates her idea with an analogy of two horses pulling a cart. One is the thyroid and the other is the adrenal.
“So if the adrenal is getting weaker, the thyroid isn’t going to try to drag them along. It will actually slow down to compensate for its weaker partner,” she said.
The adrenal glands sit on top of the kidneys. They produce sex hormones and cortisol. Somewhat like the battery of the body, our adrenals give us our get up and go—think of adrenaline, a hormone, which bears the gland’s name. Adrenal burnout is characterized by exhaustion, inflammation, sweet cravings, irritability, and depression.
Schippel said that even if someone is on thyroid medication, or even if they’ve had their thyroid removed, providing adrenal support is essential to improving health and feeling better.
“I firmly believe that it’s adrenal first and thyroid second. I really do,” she said.
The standard treatment for hypothyroidism is a synthetic equivalent of thyroxine (T4)—the most abundant hormone that the thyroid produces. The drug is known as levothyroxine or the brand name Synthroid—the most prescribed drug in America.
But even with Synthroid treatment, some patients may still have hypothyroid symptoms. However, some do find relief with the addition of another thyroid hormone known as T3, which is available through the drug Cytomel, or from medicine made from desiccated pork thyroid gland, which naturally contains both T4 and T3.
This is another bone of contention in thyroid diagnosis and treatment. The prevailing wisdom is that our bodies are able to convert some T4 into T3, so there is no reason to supplement with T3. However, many doctors find that the addition of T3 benefits some patients, including presidential hopeful, Hillary Clinton who takes a pig derived thyroid medicine.
Getting the Right Dose
In addition to identifying thyroid problems, the TSH test is also used to determine the proper dose of thyroid medication. But Kellman takes issue with the traditional reference ranges for normalcy.
“I do believe that one of the biggest problems is that a lot of people are being under medicated,” he said. “For some on Synthroid, the answer is just raising the dose and that will make them feel better. For others, they need the T3. It’s pretty individualistic. And each person really has to be evaluated in a really personalized way.”
Getting the dose of thyroid medication right is a tricky balance. Too high of a dose can lead to an overactive thyroid with symptoms such as anxiety, diarrhea, and heart palpitations. But restricting treatment within the conventional reference range may present heart problems too.
“Studies show that even a TSH above 2.5, for example, which most doctors would call normal, can lead to cardiovascular disease,” Kellman said. “So what we thought was subclinical and not so important to some people could be very problematic.”
From Schippel’s point of view, relying on synthetic hormones is not a sustainable plan.
“People go on the Synthroid, they feel a little better at first, and then they plateau so then they want more,” she said. “If you take away the job of the thyroid gland—you give it what it’s supposed to be producing—what are you going to have now? You’re going to have a lazy gland. If you quit working one arm for two weeks, watch and see how the muscles atrophy.”
Herbs and Nutrition
Patients on any T4 prescription are expected to stay on the drug for the rest of their lives, but according to Schippel’s clinical experience, it doesn’t have to be a life sentence.
“There are unbelievable alternatives to the synthetic hormones, and if they haven’t destroyed the thyroid gland through medication, or suppressed it and caused atrophy because of taking a really high dose for years and years and years, of course the thyroid imbalance can be healed,” she said.
Instead of medicating with hormones, Schippel uses herbs and nutrition, which she said heals the root cause of the imbalance.
“You have to ask the question: if the body isn’t producing enough of a hormone, then why? Is it getting the proper signal from the pituitary? If TSH is up, Free t4 and t3 are down, the pituitary is fine but the thyroid is not responding, then we have to consider what help it needs,” she said.
“Instead of just giving it T4, why not just look at the nutrients that are necessary? Why don’t we look at iodine, the broad base of B vitamins, trace minerals? Why not do that instead and let the thyroid improve because now it’s getting the nutrition that it needs?”
Two key herbs Schippel uses in her protocol are ashwaganda and bladderwrack. These herbs are restorative to the thyroid (ashwaganda also helps support the adrenals and helps regulate cortisol production). Both herbs have been shown to improve T4 and T3, and the conversion of T4 to T3.
Like Schippel, Kellman also includes minerals (selenium, iron, and iodine), and some herbs in his protocol, as well as getting patients to eliminate soy products from the diet. When environmental toxicity looks like the cause, detoxification programs may be necessary. For autoimmune disorders, Kellman works to restore gut microbiome health.
“There’s a lot to do with treating thyroid disease and it’s not just about dispensing medication, because you still want to get to the underlying causes. You still want to reduce inflammation. You still want to reduce the toxin burden,” he said.