First things first, where the heck is the thyroid gland and why should I care?
The thyroid gland is a relatively small organ that is located near the base of the neck. Fun + random fact: it kind of looks like a butterfly!
Amongst other things, the thyroid is responsible for the release of hormones that help control our metabolism as well as other vital bodily functions including our body temperature, cholesterol levels, heart rate, peripheral and central nervous system and even our breathing. For ladies, thyroid health also impacts menstruation.
The thyroid is responsible for hormone production and uses iodine, an essential mineral found in the food we ingest, to make 4 main hormones: T1, T2, T3 and T4. It is important to note that T3 is the “active” form of the hormone in our body (can enter the cells), while T4 is the “inactive” form (cannot enter the cells).
An appropriate balance between T3 and T4 is vital for hormonal health and is regulated by our brain, or more specifically by the hypothalamus. How does this regulation take place you wonder? Our hypothalamus and pituitary gland (a tiny glad attached to the base of the brain) are in constant communication - the hypothalamus produces Thyrotropin Releasing Hormone (TRH), which stimulates the pituitary gland to release or control thyroid stimulating hormone (TSH) levels accordingly.
So, if T3 and T4 levels are high, the pituitary gland releases TSH and the production of T3 and T4 reduces. On the other hand, if T3 and T4 levels are low, the pituitary gland increases the release of TSH and the thyroid gland makes more of these hormones.
How does inactive T4 turn into active T3? With the help of our gut!
A healthy gut flora contains a bacterial enzyme known as intestinal sulfatase, that converts T3 into T4. Interestingly enough, if there are issues with this conversion or if our gut not optimal, T4 has a “backup method” of conversion, that, if used too frequently, can lead to a series of trouble: T4 can convert into “Reverse T3” (instead of T3), and might eventually start competing with T3 when enter the cells. If a person is under chronic high stress and/or has poor gut health, Reverse T3 can even become “metabolically inactive”, which can lead to irregular cortisol level release and, eventually, “adrenal fatigue” - a collection of nonspecific symptoms many people with autoimmune disease experience, such as body aches, fatigue, nervousness, sleep disturbances and digestive problems.
when looking at thyroid function in depth, it’s easy to see why gut health and stress reducing exercises are so important.
Too much T3 and T4 is referred to as HYPERthyroidism and can cause mental irritability, moodiness and anxiety, hair loss, menstrual irregularities and or very light periods.
Too little T3 and T4 is referred to as HYPOthyroidism and can cause fatigue, brain fog, insomnia, dry skin and hair, heavy menstruation + increased cramping and depression.
Contact me for to inquire about extensive thyroid panel assessments and grab my FREE eBook about nutrition for Hashimoto’s thyroiditis here.
References
Knezevic J, Starchl C, Tmava Berisha A, Amrein K. Thyroid-Gut-Axis: How Does the Microbiota Influence Thyroid Function?. Nutrients. 2020;12(6):1769. Published 2020 Jun 12. doi:10.3390/nu12061769
Ishaq HM, Mohammad IS, Shahzad M, et al. Molecular Alteration Analysis of Human Gut Microbial Composition in Graves' disease Patients. Int J Biol Sci. 2018;14(11):1558-1570. Published 2018 Sep 7. doi:10.7150/ijbs.24151
Knezevic J, Starchl C, Tmava Berisha A, Amrein K. Thyroid-Gut-Axis: How Does the Microbiota Influence Thyroid Function? Nutrients. 2020; 12(6):1769. https://doi.org/10.3390/nu12061769
