Your thyroid gland controls your metabolism – essentially, how fast and efficiently your body burns its fuel; and if you have low thyroid function, you may experience any or all of the following symptoms:
- weight gain
- dry skin
- thinning at the outer edges of your eyebrows (Queen Anne’s Sign)
- depression or mental fogginess
- hair thinning, hair loss or coarse hair
- brittle nails
- feeling easily chilled
- menstrual irregularities or fertility problems
- swelling at the base of your throat or a difficulty swallowing
- muscle or joint pain
Over the last 10 years of practice, I have found a shockingly large number of patients dealing with hypothyroidism (low thyroid function). I don’t know if this is somehow a function of the times we live in, or maybe it’s more common in the Northwest, or maybe it’s just that I screen everyone for it and so I find it more often. Whatever the reason, I now test everyone’s thyroid function when I run their initial intake bloodwork, and I do this by testing not just TSH (the hormone most frequently used to test for thyroid dysfunction) but also Free T3, Free T4, Anti-TG, Anti-TPO, and Serum Iodine. Let me explain what all of that means…
Below is a rough diagram of a head and neck. At the base of the neck is the thyroid gland and in the center of the brain are the hypothalamus gland with the pituitary gland just below it. The hypothalamus and the pituitary are the control centers for the endocrine system, which is a system of glands located throughout the body that secrete hormones for various functions. Your pancreas, adrenal glands, and your ovaries/testes are all part of the endocrine system along with other glands like the thymus, parathyroid glands, pineal gland (or pineal body) and of course the topic of this discussion – the thyroid gland.
The thyroid gland makes and secretes the thyroid hormones T4 (thyroxine) and T3 (triiodothyronine). These are essentially the same hormone except that T4 has four iodine molecules and T3 has three iodine molecules. T4 the storage form and T3 is the active form of the hormone. When the body needs more active thyroid hormone, it pops one of the iodine molecules off of the T4 and voila! you have T3 (active thyroid hormone).
T4 & T3 are secreted into the blood. The blood flows through the body and eventually through the brain, where the hypothalamus monitors the levels of thyroid hormone in the blood. If there is not enough thyroid hormone in the blood to maintain a good metabolism, the hypothalamus tells the pituitary to send a messenger to the thyroid gland, telling it to kick up production. This messenger is TSH or Thyroid Stimulating Hormone. This hormone is commonly used as a screening test for low thyroid function because we know if the level of TSH in the blood is high, that the pituitary has been whipping the thyroid gland to make it work harder, so we can deduce from that, that the thyroid must not have been making enough hormone. The problem with only testing this, is that I have often seen the TSH be normal and the other thyroid markers be skewed.
The other factors that can play into this scenario are the auto-antibodies. Antibodies are things made by your immune system, that are used to flag foreign things for destruction. For example if you get a cold virus, your body recognizes it as foreign and makes antibodies against it. These antibodies flag the virus and mark it for destruction. Because our immune system is not a perfect system, there are sometimes glitches in it and occasionally the immune system makes antibodies against our own stuff instead of just foreign stuff. These antibodies against our own bodies are called “auto”-antibodies and normally they are so few and far between that they are no big deal. It’s when they start to become a regular occurrence that they begin to create health problems.
Going back to the thyroid… thyroglobulin (TG) and thyroid peroxidase (TPO) are components of the thyroid gland that are used to make thyroid hormone. I always use the analogy that they are like the factory machinery in thyroid gland factory. So here you are, you have the thyroid gland factory, and all the workers in the factory are chugging along making thyroid hormone to meet their production deadlines. All is going well until all of a sudden there are all these auto-antibodies (Anti-TG & Anti-TPO) attacking your machinery (the TG – thyroglobulin & the TPO – thyroid peroxidase). Now the thyroid gland essentially has to divert resources from making thyroid hormone, to dealing with this attack; production slows down and so does your metabolism. Of course this is a gross oversimplification of the entire process, but it makes it a little easier to understand what is going on. An elevation in the level of Anti-TG and/or Anti-TPO can indicate that a person has what is called Hashimoto’s Disease which is an autoimmune disease in which a person’s own immune system is attacking their thyroid gland. There are many potential causes of thyroid dysfunction, but Hashimoto’s is one that I see quite frequently, so frequently in fact, that I now screen everyone for it.
The Role of Iodine
Again, I don’t know why I see so much hypothyroidism in my practice (primary and Hashimoto’s), but there are a couple of things that I always consider when I do find it. The first one is quite simple – Iodine. Here in the Northwest, many people use sea salt rather than iodized, mined salt. The flavor of sea salt is so much more subtle and can really bring out the flavor of foods in a way that regular salt does not. However, most sea salt does not have iodine added to it. Iodized salt is one of the main ways that we get iodine in our diet and in fact, it was because of chronic low iodine and the subsequent low thyroid problems, that iodine began being added to salt. Remember that iodine is a key component of thyroid hormone, so if there’s not enough iodine in the body, you simply cannot make enough thyroid hormone. Sources of iodine include seaweed and some seafood and well as small amounts in other foods. Because of heavy metal toxicity and overall chemical pollution in the oceans, the vast majority of seafood is not really a health food any more (I consider it a treat not a staple), so I don’t generally encourage folks to eat large amounts of seafood, and Iodized salt then often becomes the main way people get iodine.
About six months ago, I got curious and started testing people’s serum iodine levels. Now granted, it’s not the most accurate way to test iodine levels (to test accurately, this is a much more involved test) but it gives me a good ballpark idea of where people’s iodine levels are running; and what I was shocked to find, was that nearly everyone was low. Those who were low were almost always eating sea salt or some other non-iodized salt and those who were ok, were generally eating iodized salt. These low results also often correlated with lower thyroid function.
The Immune System Freak-Out
Going back to the very basics, this is a picture of the human body (See The Inside of the Tube for more on this). If you think about it, we really are essentially a tube, with the mouth at the top and the bum at the bottom (pun intended). Now consider… because this is where the outside world comes in, we have lined a very large chunk of our immune system along the inner walls (the digestive tract) of this tube (our body).
When we have chronic gut inflammation for whatever reason (for example daily eating of some food we may be sensitive to), it causes the immune system in the gut to become overstimulated. I think that when the immune system in our gut is chronically under “attack,” after a while it freaks out and “talks” to the rest of the immune system, which then starts blowing things up it’s not supposed to – like your thyroid.
It is very common in naturopathic medicine that when we are addressing autoimmune disease, we begin by working on improving the health of the gut. I can’t say that there is a direct correlation between eating foods you’re sensitive to and the development of autoimmune diseases, but I can say that people do seem to improve as the health of their gut does. And I can say that I see both a ridiculously high number of people with Autoimmune thyroid disease (Hashimoto’s) and a ridiculously high number of people with food sensitivities. It could be that I see them both because I look for them, it could be I see so much of them because they are both on the rise and it could be that there is some distinct relationship between the two. I can’t say for sure.
Adrenal Fatigue – The Chicken Or The Egg?
Another possible contributing factor I am starting to look at is adrenal fatigue. Because the glands of the endocrine system are all so interconnected, I am beginning to think that adrenal fatigue, which is also incredibly common in my patients, is exacerbating or potentially even causing much of the thyroid dysfunction that I see. Regardless, both of these things seem to frequently happen together, so treating the adrenals is going to benefit these people whether it is part of the thyroid problem or not.
Ideal Lab Results
- TSH right around 1.5 uIU/ml. Once it starts climbing up much over 2 – 2.5, people often start to experience symptoms of low thyroid function, or hypothyroidism. Some labs still consider a TSH of up to 5 uIU/ml to be acceptable, but if your TSH is that high you are very likely to be dragging in the dirt, tired.
- FT4 & FT3 right in the middle of the given range (ex. around 1.25 ng/dl for T4 & 3.1 pg/ml for T3)
- Anti-TPO & Anti-TG less than 20 U/ml
So in summary, if you’re experiencing any of the symptoms listed at the beginning of this chapter, please consider getting your thyroid tested. Keep in mind that many of the symptoms can be caused by other things, but if you have a suspicion that your thyroid function might not be up to snuff, it wouldn’t hurt to have a chat with your doctor and have it tested.