Demystifying the Thyroid: Breakdown of the Basics
Written by Emily Edmonds
In today’s fast pace and stressful world, thyroid disease is becoming more common and more problematic than ever before. The function of our thyroid impacts so many biochemical and physiological processes in our body that support our health. In this series, we are going to talk about the thyroid, how it affects our health, how it impacts fertility, and how we can improve our health so that our thyroid works the way it was designed. We are going to talk about what can cause thyroid disease, lab tests, supplementation and dietary measures to support thyroid health. We are also going to talk about some common culprits that you may not be aware of that could be causing your thyroid to be out of balance.
The thyroid is a butterfly shaped gland located near the base of your throat. The thyroid is an endocrine gland that secretes thyroid hormones which influence metabolic rate, protein synthesis, and growth and development. The thyroid produces three hormones – triiodothyronine (T3), and thyroxine (T4) and calcitonin. Most thyroid diseases involve the production of T3 and T4, but some less common thyroid conditions can be caused by disruptions of hormones produced in the brain which influence the production of these hormones.
Thyroid hormones govern the function of many processes in our bodies. The most well-known function of thyroid hormones is in regulation of our basal metabolic rate. They stimulate the breakdown of fats, glucose, regulate appetite, gut motility and the absorption of nutrients. On a cardiovascular level, thyroid hormones increase the rate and strength of the heart. Thyroid hormones also influence the rate of breathing, oxygen intake, and activity of the mitochondria (cellular function which produces ATP and energetic function). These factors influence blood flow and body temperature. Thyroid hormones also play a role in reproductive health, growth and development. They play a major role in brain maturation during fetal development and for the first few years of post-natal life. Thyroid hormones also influence sexual function, the menstrual cycle, sleep and cognition.
With the numerous important functions in our bodies the thyroid influences, it is certainly understandable why thyroid disease can make patients feel terrible!
Thyroid hormone production is regulated by a closed loop cycle. The hypothalamus produces a hormone called Thyroid Releasing Hormone (TRH) which reaches the pituitary gland. The pituitary gland receives TRH and releases Thyroid Stimulating Hormone (TSH). Most physicians will diagnose more common diseases by testing for TSH, and I will explain more on this later. TSH stimulates the thyroid to release T4 and some T3. This mechanism is tightly regulated by a negative feedback loop, meaning that when T4/T3 are low, TSH will rise to stimulate the thyroid to produce more thyroid hormone. When T4/T3 are high, TSH will be reduced so the thyroid doesn’t make too much. Many hormonal glands operate in a similar fashion, including our adrenal glands and our reproductive system. T4 is the inactive form of thyroid hormone. It needs to be converted to T3 to be considered metabolically active. When these are released into the bloodstream, T4 is converted into its active form T3. Conversion of T4 to T3 is influenced by a number of different ways, mostly by liver function but also by gut bacteria, kidneys, brain, and skeletal tissue. Thyroid hormone conversion is very important and is at the root of a lot of common thyroid diseases and requires certain key nutrients and healthy organ function.
Since there are a number of organs and processes in the body that require thyroid hormone conversion, uptake, and metabolism – diseases of the thyroid are sometimes thought to be more of a canary in the coal mine rather than a problem of the thyroid alone. But if you have a thyroid condition, it is very important that you get treatment with a physician to help with the thyroid itself, and with a holistic practitioner with some knowledge of thyroid disease who can help with the entire body so that the cause of the thyroid condition can be healed.
There are many different types of thyroid disease. Thyroid diseases fall into two main categories – hypothyroidism and hyperthyroidism. Hypothyroidism results when there are too few thyroid hormones in production and circulation. Hyperthyroidism results when there are too many thyroid hormones in production and circulation. There is acute thyroiditis, which usually results from a viral infection and typically resolves on its own. Postpartum thyroiditis, which occurs in women after childbirth and also is a temporary condition. Some of the most common thyroid diseases are autoimmune in nature. These include Hashimoto’s disease and Grave’s disease. Hashimoto’s thyroiditis is an autoimmune disease where the thyroid gland is being targeted by the immune system. This results in hypothyroidism, which is a condition that develops where there are not enough thyroid hormones in circulation. In the US at this time, Hashimoto’s disease is the most common cause of hypothyroidism. Grave’s disease is an autoimmune disease which results in hyperthyroidism, which is when thyroid hormone levels are too high. In poorer countries, hypothyroidism is most commonly caused by iodine deficiency. But excessive iodine can also significantly worsen thyroid conditions, most especially hyperthyroidism but in many cases of hypothyroidism as well. We will talk about iodine and why it’s not actually a great solution to treating hypothyroidism caused by autoimmune illness such as Hashimoto’s disease in a future article.
There are also thyroid conditions that are congenital. Many of these diseases are caused by problems with the pituitary gland secreting TSH, or it can be a problem with the hypothalamus producing sufficient TRH. The thyroid will have a problem with producing adequate amounts of thyroid hormone due to not receiving these signals from these glands in our brain to produce adequate thyroid hormone. This is called secondary hypothyroidism. These conditions are rare though so we will not be discussing those as much for the purpose of this series.
Traditional Chinese Medicine doesn’t have one specific disease attributed to thyroid disease alone. It views thyroid disease as more of a consequence from an existing imbalance, rather than a cause of disease. As I mentioned earlier, there are several major organ systems in our bodies that have an impact on how thyroid hormones are processed and metabolized. Often, thyroid disease starts for one reason and continues for another. These factors can include stress, infection, toxicity, gut microbiome, and poor diet. We can think of the thyroid as being the victim rather than the perpetrator, so focusing on treating the thyroid alone is often not as helpful as focusing on the cause of thyroid disease. Traditional Chinese Medicine is a holistic approach on thyroid disease and focuses on the body healing itself so that the thyroid can heal itself.
Healing from thyroid disease is a multi-faceted approach. It requires a complete change of lifestyle. These changes include dietary, environmental, mental-emotional, exercises, sleep and rest. There is still more research being done on how acupuncture and Chinese medicine can help with thyroid disease, but it is clear that Chinese medicine can help with improving energy levels, sleep, appetite, digestion, mood and emotional stress all associated with thyroid disease.
Stay tuned for our upcoming article on thyroid nutrition and what key nutrients are needed for optimal thyroid function.
