156 Hyperthyroidism or Hypothyroidism? Reasons for Fluctuating TSH

Shortcut to my thyroid program.

The Case: 

Lucy was experiencing symptoms that went back and forth

She would experience heart palpitations, hot flashes, and anxiety and then she’d have periods of fatigue

Her doctor suspected hyperthyroidism and tested her for Graves

I knew that there was reason to investigate further because her symptoms weren’t adding up. When it comes to hyperthyroidism, there’s one person I often turn to - Dr. Eric Osansky, a chiropractor and host of the ‘Save My Thyroid’ podcast. 

His interest in hyperthyroidism comes from his personal Graves diagnosis in 2008. He is also the author of 2 thyroid books, ‘Natural Solutions for Hypothyroidism and Graves’ Disease’ and ‘Hashimoto’s Triggers: Eliminate Your Thyroid Symptoms by Finding and Removing Your Triggers’

On this show, we talk a lot about hypothyroidism and how Hashimoto’s can be at play. Many don’t think that Hashimoto’s can also be present when someone has an overactive thyroid (Hyperthyroidism and sometimes Graves’ Disease). It all starts by looking at and understanding TSH levels. 

Reviewing the Basics of Thyroid-Stimulating Hormone (TSH)

The thyroid gland is a critical component of our endocrine system, responsible for regulating our metabolism. When it comes to thyroid assessments, most practitioners start by examining the Thyroid-Stimulating Hormone (TSH). Dr. Osansky explained that TSH stands for "Thyroid Stimulation-Communicating Hormone" and is produced by the pituitary gland. This hormone plays a vital role in communicating with the thyroid and serves as a fundamental element of many thyroid evaluations.

When it comes to hypothyroidism, including conditions like Hashimoto's, you'll often see elevated TSH levels. This is because the thyroid hormone in the body is on the lower side. It might be just within the lab's reference range, or it could be overtly low. In response, the pituitary gland sends a clear signal to the thyroid: "We need more thyroid hormone!" This signal takes the form of an increased TSH level, prompting the thyroid gland to produce more thyroid hormone.

Conversely, in the case of hyperthyroidism, it's the complete opposite. With hyperthyroidism, there's an excess of thyroid hormone circulating in the bloodstream, mainly bound to proteins. In this scenario, the pituitary gland signals the thyroid to slow down production. As a result, you'll commonly observe not only low TSH but sometimes an undetectable TSH, especially in conditions like Graves' disease. This undetectable TSH indicates that the pituitary is working hard to halt the overproduction of thyroid hormone. So, while TSH levels can provide valuable insights, they're just one piece of the puzzle. We need to dig deeper into the thyroid hormones to get the full picture. 

Comprehensive Thyroid Testing is Always Key

According to Dr. Eric, to reach a proper diagnosis, we must also examine the thyroid hormones, particularly free T3 and free T4. These free hormones offer a more accurate representation of thyroid function. In hyperthyroidism, where the thyroid hormones are typically elevated, examining free T3 and free T4 alone is often sufficient because total hormones will also be elevated. On the other hand, in hypothyroidism, some practitioners prefer to assess not only free hormones but also total hormones to gauge production since a significant portion of thyroid hormone is bound to proteins.

Let's not forget reverse T3, an inactive form of T3. It's a bit of a controversial character in the thyroid world. Some suggest that reverse T3 may act as a blocking agent, especially in hyperthyroidism. Elevated reverse T3 levels are common in this condition, further hinting at its role in dampening excessive thyroid hormone activity. 

But the thyroid's complexity doesn't end here. We also need to consider antibodies, which play a crucial role in autoimmune thyroid conditions like Hashimoto's. Plus, keep in mind that it's not just the thyroid at play; the pituitary gland could be throwing a wrench in the works too. Pituitary issues, such as a pituitary adenoma, can also affect TSH levels and the overall thyroid regulation. So, always remember that a comprehensive view is essential when evaluating thyroid health.

What is Hashi-Toxicosis? 

Hashi-toxicosis is a fascinating term that combines "Hashimoto's" and "toxicosis." It essentially refers to Hashimoto's thyroiditis with intermittent episodes of hyperthyroidism. When someone has Hashimoto's, the autoimmune attack damages the thyroid gland, causing it to release excessive thyroid hormone into the bloodstream. Consequently, when you get a blood test during such an episode, it can appear as hyperthyroidism. However, it's different from Graves' disease, where specific antibodies continuously stimulate the thyroid gland. In Hashi-toxicosis, these episodes of hyperthyroidism are transient, meaning they come and go. The duration varies from person to person, some experiencing these episodes for a few hours, while others may have them for a few days.

These fluctuations can be triggered by various factors. For some, hormonal changes, like those related to the menstrual cycle or stressful events, can lead to these episodes. It's important to note that the frequency of these flares varies among individuals. Some may experience them frequently, while others only encounter them occasionally. In my own journey, I've had a couple of Hashi-toxicosis flares, both linked to high-stress events – one after moving and the other postpartum. These personal experiences have taught me that hormonal changes can significantly influence the frequency of these episodes. For those who face occasional flares, it can be a bewildering experience. 

When I had my first episode, nearly two decades ago, it looked a lot like Lucy's situation. The doctor ran tests during a flare, and my thyroid hormone levels were off the charts. Not just my TSH, but all my thyroid hormones were elevated, which was rather unusual. The doctor even suggested the possibility of thyroid removal. Thankfully, my knowledge about Hashimoto's helped me question this recommendation, as I knew there was more to the story than met the eye.

Get Curious About Unusual Thyroid Results

It's absolutely crucial to explore all the possibilities when dealing with thyroid issues and stop the attack on our thyroid gland. Now, consider a scenario where someone, like Lucy, has a low TSH and elevated hormone levels. If it's not clear whether this is a transient episode, it's essential to retest and, most importantly, assess the antibodies. But what if the antibodies turn out to be negative, including TSI? What else could be behind these hyperthyroid symptoms and unusual lab results? 

Dr. Osasnsky introduced the possibility of subacute thyroiditis. This condition often arises from viral infections, such as cytomegalovirus or even, more recently, the effects of COVID. It triggers significant inflammation in the thyroid, resulting in excess thyroid hormone production. Strangely, the presentation mirrors Graves' disease, yet the antibodies are absent. However, in most cases, within two to four months, this hyper phase shifts to a hypo state, and often, the hypothyroidism is temporary, eventually returning to a normal thyroid balance.

One more thing to consider is medication. For example, if someone is taking a hig...