The brief history of underactive thyroid treatment
In the early days of treatment, at the end of 19th and the beginning of 20th century, scientists found out that lost thyroid function can be compensated for by adding an external thyroid. Many of the severe symptoms, including death could be prevented by this discovery.
Before the 1920s, thyroid treatment started with natural thyroid preparations from cow or pig. It came in several forms: transplanted thyroid, injection of thyroid cells or eating a raw thyroid (“thyroid feeding”).
While transplantation worked for some people, the others got their symptoms back and needed to undergo series of transplantations to keep them from dying (1).
The next treatment step was injections with, and eating of, pig and cow thyroid. This was a good success, and remained a treatment option for a couple of decades (2 -4).
The most frequent problem during these early days was overtreatment. Lab diagnostics could not measure levels of thyroid hormones, the chemical structure and the exact functionality of thyroxine (T4), triiodothyronine (T3) and thyroid stimulating hormone (TSH) was still not known. As a consequence the treatment could not be adjusted appropriately. Without this knowledge it was also impossible to produce a synthetic version of the hormone in the lab.
The rise of Levothyroxine
The breakthrough in underactive thyroid treatment happened after the discovery of the structure of T4 and understanding that our body is able to convert T4 to T3. This was in the 1950s, and marked the start of Levothyroxine (T4) therapy (5). Even today, this is a major therapy approach to restore low thyroid hormone levels.
Levothyroxine became the first prescription choice for doctors in the 1970s and the medical community worked under the assumption that Levothyroxine was the one-cure-fits-all solution. However, it quickly became apparent that the drug didn’t work for a pool of people. In the beginning, the remaining symptoms in patients were attributed to other diseases, or it was believed that patients were not compliant to the therapy (6).
With more research on the functionality of Levothyroxine it became apparent it was good for restoring blood levels of TSH to what was considered a “normal” or an average value. However, it did not fully re-activate the metabolism. Metabolism was 10%- 20% less efficient, resulting in problems with maintaining healthy weight (7, 8). Another issue were high cholesterol levels, often experienced in hypothyroidism, which did not improve with Levothyroxine treatment (9, 10).
Levothyroxine is not a silver bullet
1–2 in 10 of people with hypothyroid condition cannot convert T4 into T3 because of a faulty enzyme called deiodinase (11, 12). Enzymes are big molecules necessary for many of the chemical reactions in our body. Deiodinase removes one of the four molecules of iodine from T4, and by this process it turns it into an active hormone T3, containing three molecules of iodine.
Even for people who do not have the deiodinase-caused problem, symptoms such as fatigue, depression and anxiety remained (6). This state is caused by a disturbed balance between T3 and T4, triggered by high T4 levels coming from Levothyroxine treatment. Maintaining healthy balance is necessary for proper functioning of the whole body, and this is why a combination therapy of T3 and T4 could be a better approach, improving mood and mental well being (6). However, studies on different treatments still have conflicting results (11, 13-15).
All this knowledge helped research to understand an increased need for a more personal approach to treatment (11).
What about non-hypothyroid Hashimoto’s problems?
Lastly, we come to the unsolved part of Hashimoto’s: the immune system. While Hashimoto’s is an autoimmune disease, it is not treated as one.
How to treat Hashimoto’s?
Is cortisone an option? Cortisone was effective in other autoimmune diseases (16), but what about Hashimoto’s ?
The problem with cortisone is it’s massive side effects that might outweigh the benefit of the treatment. Side effects include water retention, swelling of arms and legs, heart problems, problems with mood, memory and other behaviors, weight gain, glaucoma, high blood sugar (which can trigger diabetes), osteoporosis (bone thinning) and slower wound healing. For that reason doctors will not likely prescribe a long-term cortisone treatment. Short term treatment also has side effects, but they will disappear after discontinuing the therapy (17).
Are there other options?
Is there anything that would allow our immune system to start resembling normally balanced and healthy system? In biology this is sometimes called re-programming. When the immune cells that have one function are basically re-educated and retrained to do another job. This re-programming can be done in several ways.
Environment triggers autoimmune diseases without changing or mutating our DNA, this is called epigenetics (18–21).
Epigenetics determine how our genetic code (DNA) is read and made into a functional protein. Epigenetic changes are responsible for a fast adaptation to the new environment, but also for a rapid onset of some diseases.
Many drugs modifying our epigenome are in use, usually for treatment of cancer, but are considered for the treatment of some of the other diseases (22).
We could try changing our immune system through changing the amount and the type of bacteria we have in our intestines (23–25).
Parasites such as worms are successfully used for treatment of some other autoimmune diseases (26, 27). They have also been shown to work successfully for fighting seasonal allergies.
Stem cell therapy would be a modern take on one of the historical treatments of transplanting an entire thyroid. With today’s sophisticated technology, we could easily get a stem cells transplant. This type of transplantation would not be a classical organ transplant and would not require a major surgery. It would more resemble a vaccination, where cells would be in a syringe and injected into the thyroid.
Hypothyroid treatment history was so far short and interesting. It resulted in a development of two main types of treatment: a single hormone therapy (monotherapy) with synthetic Levothyroxine, and a combination of T3 and T4 therapy. The combination therapy can be given as a combo of synthetic Levothyroxine (T4) and Liothyronine (T3) or as a natural thyroid preparations.
Natural thyroid preparations are coming back to use, since scientists have solved the issues of their short shelf life and have significantly improved storage sensitivity, and batch variability (28). Also, it became apparent that the initially reported side effects (angina, heart failure, palpitations, nervousness, tremor and perspiration) might not come from the natural thyroid preparations themselves, but from their incorrect dosage (29–31).
Levothyroxine is still the prefered therapy choice for most of healthcare professionals. However medical community increasingly accepts patient diversity, therefore the treatment and disease management could become more personalized.
How we write: our information is based on the results of peer reviewed studies using the National Library of Medicine platform. It is written by scientists and reviewed by external experts. If you believe we might have overseen crucial scientific information, please contact us at email@example.com
Disclaimer: This information is not intended to mitigate, prevent, treat, cure or diagnose any disease or condition. If you want to change your treatment, lifestyle, your diet, include supplements in your diet or have concerns about your health, please consult your doctor before trying new approaches.
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