According to the American Association of Clinical Endocrinologists, more than 27 million Americans have thyroid-related disorders and more than half remain undiagnosed. That said, thyroid-related diseases are often poorly diagnosed and there is much surrounding their treatment that requires more in-depth clarification and individualization.
The thyroid gland is a 2-inch butterfly-shaped organ located at the front of the neck. Although small, the thyroid gland plays a major role in the endocrine system and affects nearly every organ in the body. The thyroid regulates fat and carbohydrate metabolism, respiration, body temperature, brain development, cholesterol levels, the heart and nervous system, blood calcium levels, menstrual cycles, skin integrity, and more.
Common conditions associated with thyroid include Hyperthyroidism (which includes Autoimmune Thyroid Disease [AITD], Graves' Disease, and Thyroid Storm), Hypothyroidism (which includes Hashimoto's, Congenital Hypothyroidism [CHD] or cretinism, Myxdema, Thyroid Autoimmunity, Endemic Goiter, Subclinical Hypothyroidism [SCH], and Polycystic Ovary Syndrome [PCOS]).
Hyperthyroidism results from the over-secretion of the thyroid hormones, thiiodothyronine (T3) or thyroxone (T4). These hormones affect every cell as they help to control body temperature, heart rate, metabolism, production of calcitonin, and glucose homeostasis. Usually, in hyperthyroidism, the entire gland is overproducing thyroid hormone. Symptoms associated with hyperthyroidism include:
Some of the most common endocrine diseases associated with hyperthyroidism include autoimmune thyroid diseases (AITD), Graves’ disease, and chronic lymphocytic thyroiditis (CLT).
Autoimmune thyroid disease (AITD) may start out as a temporary concern, but it can lead to hyperthyroidism. AITD may be associated with a Hashimoto’s thyroiditis, subacute granulomatous thyroiditis, or silent lymphocytic thyroiditis. While the causes of AITD may not be easily identifiable, functional medicine practitioners work to identify if a person may have any environmental triggers or other health-related concerns that may be associated with a diagnosis including environmental triggers (medications, infection, iodine) or previous diagnosis of celiac disease, primary biliary cirrhosis, Type 1 Diabetes Mellitus, mood disorders, psychosis, and/or Addison's disease.
Graves' disease (also known as diffuse toxic goiter) is the most common type of AITD and entails a specific combination of polymorphisms for thyroglobulin and HLA-DR, as this increases the odds ratio for developing disease. Additionally, the body's autoimmune response causes the thyroid gland to produce too much T3 and T4. Note: It is common to experience periods of high and low thyroid hormone levels in those with Graves’ disease, so it may take several months to achieve a balance.
Thyroid Storm (thyroid crisis) is a potentially life-threatening condition that develops in a person with hyperthyroidism where the gland suddenly releases large amounts of thyroid hormone in a short period of time. Symptoms of Thyroid Storm include:
If left untreated, Thyroid Storm can result in shock, delirium, shortness of breath, fatigue, coma, heart failure, and even death.
Hypothyroidism ("underactive thyroid") is the most common thyroid condition, affects up to 10% of adult women, and is caused by the under-functioning of the thyroid gland (most common: inflammation cause by antibodies; second major cause: various medical treatments that affect thyroid gland [e.g., surgery, chronic medication use]).
Hypothyroidism is classified as Primary (thyroid failure, 95% of all cases), Secondary (pituitary TSH deficient), Tertiary (hypothalamic deficiency or thyrotropin-releasing hormone), or results from peripheral resistance to the action of thyroid hormones.
Hashimoto's Thyroiditis is an autoimmune response responsible for hypothyroidism in many cases and is the most common cause of thyroid gland failure. In these cases, the body mistakenly identifies its own tissues as an invader and attacks them until the organ is destroyed. This chronic attack eventually prevents the thyroid from releasing adequate levels of the hormones T3 and T4, which are necessary to keep the body functioning properly. Lack of T3 and T4 hormones can slow metabolism and cause weight gain, fatigue, dry skin and hair, and difficulty concentrating.
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Samantha Schleiger, MS, RDN, CD, CLT
Sam is a functional nutrition dietitian, certified LEAP therapist, and functional medicine beneficiary.