Even though far too many patients with symptoms of low thyroid are not adequately treated, Levothyroxine (Brand name: Synthroid®) has been one of the top 5 most prescribed medication in the Unites States for many years running. Beyond that, Synthroid is often NOT the best treatment for patients needing thyroid supplementation. So, the questions are: How does the thyroid work? what is Synthroid®? What is “natural thyroid”? Why is Synthroid so commonly prescribed? Why is it that natural thyroid is, so often, mocked by the traditional medical community? What should I do if I need thyroid supplementation?
The thyroid is a butterfly shaped gland located in the lower neck, in front of the voice box. It is the producer of a life critical series of hormones, the most important of which are called Thyroxine (T4) and Tri-iodothyronine (T3). Without these two hormones (the most important of which is T3) life would be impossible. Thyroid hormones regulate almost every tissue and organ in the body. When the thyroid is low, a patient might experience symptoms of sluggishness and fatigue. Others include cold intolerance, brain fog, trouble concentrating, brittle or thinning hair, weight gain, menstrual irregularity, infertility, depression, and improper metabolism of blood sugar or cholesterol. In fact, almost every organ system and tissue in the body needs thyroid hormones for proper function.
Many people have true hypothyroidism, a condition where a constellation of low-thyroid symptoms is accompanied by a measurably low level of thyroid. Interestingly, perhaps even a greater number of people have symptoms of low thyroid yet have “normal” levels of thyroid hormone. It is these patients that often present a treatment quandary for traditional medicine.
The thyroid gland produces hormones in response to signaling from the pituitary (a small pea sized gland in the brain). In a perfect world, when the pituitary senses a lowering of thyroid hormone, it sends a signal in the form of another hormone called Thyroid Stimulating Hormone (TSH). The TSH gives the thyroid gland a “wake up call” and causes it to start producing thyroid hormone – about 90% of which is T4 and most of the remaining 10% is T3. While T3 is the “active hormone”, that is it is the one that causes the tissues or the organs to be healthy and carry out their functions properly, it has a short half-life, meaning that it does not last long in the body. So, to make sure that there are adequate supplies of T3, the body produces T4 that is in a higher concentration in the blood, yet it has a longer half-life, meaning that it hangs around longer. When the body needs more T3, the body uses a special protein called an enzyme along with some co-factors like zinc, iodine and selenium to remove one iodine molecule and thus convert T4 into T3 (a process called deiodination). There is then a supply of T3 to act on the organs and tissue to produce the life enhancing effects.
If one assumes that the process of conversion of T4 into T3 is efficient and constant, then when a patient was to develop a reduced production of T4 that led to symptoms (classic hypothyroidism) and when that patient needed “thyroid replacement” a simple replacement of T4 should be adequate. It would increase the stores of a hormone that lasts a long time in the body and is easily converted in the active hormone T3. Those are the assumptions necessary to understand the use of Synthroid® (a synthetic hormone made to mimic T4). With millions of people suffering from true hypothyroid, it is easy to see why the production and sales of Synthroid® has reached the fantastic levels it has.
However, there is a potential HUGE problem. Many people, particularly older people and those that suffer from illnesses like diabetes and other chronic conditions, do not metabolize T4 into T3 effectively. So, when T4 is given, its level can be measured to rise. The pituitary senses the rise in the T4 and feels “satisfied” that there is enough thyroid hormone in the body, the pituitary then reduces the amount of TSH that is produced. The thyroid may eventually stop all production of any thyroid hormone, even the essential T3. In some instances, particularly in people who do not convert T4 into T3 effectively, when these people are given T4 (Synthroid®) their symptoms might even get WORSE when T4 is administered because what little T3 that was made by the thyroid gland itself has ceased due to the feedback system reduced production of TSH by the pituitary. This is what is known as a “paradoxical effect”, that is when given “Thyroid Hormone – T4”, the patient actually gets worse rather than better.
Enter – “Natural Thyroid”. Natural thyroid is a purified product derived from porcine thyroid (though it can be compounded from purified hormone in a compounding lab to avoid potential issues with food limitations of some ethnic and religious groups). It is harvested, purified and used very effectively to replace thyroid hormone in deficient patients. Natural Thyroid has a near normal balance of T4 and T3 in approximately the same percentages as is produced naturally by the patient’s own thyroid. So, when it is eaten and gets absorbed into the body, the body senses an effect more like the natural production of Thyroid hormone. Since T3 is the active hormone, by taking it as a supplement, it is more easily assured that there are adequate amounts of T3 in the body.
Years ago, natural thyroid was not regulated by the FDA. Consequently, the natural products on the market varied widely in the reproducibility of their dosing and effectiveness. As a result, the early use of natural thyroid led to variable and many times ineffective results in patients. Rightly, natural thyroid back then was considered ineffective and inefficient. However, in recent years, the manufacture of natural thyroid has become much more highly regulated by the FDA and the USP (United States Pharmacopeia) resulting in a product that is reproducible and able to give solid medical support. However, to this day, there are many in the medical community that still believe that natural thyroid products are substandard despite the solid standardization of the dosing that exists today. Thus, their historically fact based but currently incorrect belief that natural thyroid products are not good. However, there are several studies that do confirm that natural thyroid may in fact be superior to Synthroid®.
In a 2013 article in the “Bible” of endocrinology (The Journal of Clinical Endocrinology and Metabolism) natural thyroid was compared to Synthroid®. This was an excellent study done according to very rigorous investigative guidelines. The researchers concluded that “thyroid hormone therapy with [natural thyroid] in place of [Synthroid® led to] weight loss and possible improvements in [thyroid] symptoms and mental health without appreciable adverse effects.” The conclusion is clear, natural thyroid products that have T3 produced better results than synthetic thyroid products containing T4 only. And that a combination product with T3 and T4 gave better outcomes. Indeed, this conclusion is supported by several other articles in leading journals (one of which is the New England Journal of Medicine – the Bible of all medical journal Bibles). In an article in the 1999 volume of the NEJM the authors concluded that a natural product containing both T3 and T4 “may be an improvement over standard [T4] treatment for patients with hypothyroidism”. And there are others. The literature is clear: combination T3/T4 products (like that in natural thyroid) consistently give better clinical results that single compound (T4 only) products like Synthroid®.
The treatment of patients with significant thyroid symptoms is widely prevalent in medicine today. Despite Synthroid® being one of the most commonly prescribed medications today, I would argue that there are many more patients with symptoms bothersome enough to require treatment. Using thyroid “off label” as a supplement in these patients can produce life altering effects in terms of mental focus, energy and improvement of fatigue. And the medical literature does demonstrate that symptom improvement using a natural thyroid product can be far superior to the synthetic thyroid products on the market. Finally, treating symptoms rather than numbers will produce a healthier, happier and more vital patient population.