Thyroid Hormone

Having a TSH blood test is part of normal bloodwork. These tests may to drug treatment (usually Synthroid), but are underactive thyroid symptoms dangerous?

Let’s cover some basics first.

The thyroid plays a huge role in just about everything we do (so does the adrenal–but that’s fodder for another post) and is critical for good health. It produces two hormones: triiodothyronine (T3) and thyroxine (T4). T3 is much more active than T4, but the body breaks it down much faster. So, in its brilliance, the thyroid makes mostly T4 and sends this hormone into the circulation. When it gets to organs like the liver, kidneys, heart and brain enzymes here convert T4 to T3 to be used on site. Pretty smart if you ask me.

Healthy production of T4 in the thyroid depends on several factors such as iodine, TSH levels and chemical exposure. Many, many chemicals affect thyroid hormone production. Some of these chemicals that lead to underactive thyroid symptoms have been addressed in a previous post. This means that treating low TSH levels does NOT begin with medication, but rather by a complete look at what might be leading to a slow thyroid gland.

Then, once T3 gets to the organ, it requires nutrients like selenium to be properly converted to T4. Many patients are put on thyroid medications when the real problem may be as simple as selenium deficiency. Stress also destroys this process, leading to the production of a compound called reverse T3 (which is inactive) instead of the desired T3. So if underconversion is your problem, again meds are not the answer–stress management and supplementation are better options.

Overall, I think we have a very messed up way of addressing thyroid problems. First of all, what if your heart or liver started to fail in your twenties?  Would we throw up our hands and say that it just happens? Of course not.  If something is wrong with those organs we’re going to damn well get to the root of the problem and fix it. But for some reason the thyroid is treated differently. Maybe it’s because we have a medication that “fixes” the problem.

The other issue is how we compare the patient and the lab values. Normally, you consider the two in conjunction and use each to guide treatment options. Not so with the thyroid. You can have a patient who has the entire laundry list of underactive thyroid symptoms but normal labs. In this case the doctor just tells the patient that the thyroid is ok, completely ignoring the patient’s story. On the other hand, I have had patients who have been put on Synthroid without a shred of symptoms but had high or low TSH levels.

So what happens if we treat solely based on TSH blood tests and not on patient’s underactive thyroid symptoms?

This particular study should make us think twice about blindly treating thyroid disorders without understanding what is going on. Researchers looked at how thyroid related blood values played a role in a group of patients (around 72 years old) followed for 13 years and his or her risk of dying. Here’s what they found:

1. Over the 13 years, levels on the TSH blood test went 13%
2. T4 levels increased 1.7%
3. There was a 13% decrease in total T₃
4. Subclinical hypothyroidism, TSH levels and TPO antibodies had no effect on the risk of dying
5. T4 levels, however, greatly increased the risk of death-257% for each ng/dl increase

Clearly, higher levels of T4 led to more problems and a shorter lifespan in the participants of this study. So what does this mean?

It can mean several things, but what seems to be staring me in the face is that maybe the body is supposed to slow down its metabolism as we get older. Much like menopause, the body slows things down for a reason.  Decades of abuse from stress, poor quality diets, sedentary lifestyles and environmental chemical exposures damage our genes. At this point, more metabolic activity may not be a good thing, leading to things like cancer and brain cell damage.

Keep in mind that standard medical approaches to thyroid problems involve almost exclusively T4 (Synthroid, levothyroxine). Based on this information, does this sound like a good idea, especially over the course of 30, 40 or 50 years?