Hypothyroidism - what happens, symptoms, causes, complications, natural remedies
what happens?
Let me explain how the thyroid works, first.
The thyroid gland is situated on the frontal part of the neck, in front of the trachea, full of thyrocytes, which synthesise and secrete thyroid hormones. The function of the thyroid is regulated by the hypothalamic-pituitary-thyroid axis (HPT axis). The hypothalamus (located in the brain) secretes thyrotropin-releasing hormone (TRH), which then stimulates the anterior pituitary (also in the brain) to produce thyroid-stimulating hormone (TSH). TSH then travels in the blood to the thyroid gland (located in the neck), and stimulates the thyrocytes to produce and secrete the thyroid hormones, triiodothyronine (T3) and thyroxine (T4). T3 and T4 then act as ‘regulators’ of TRH and TSH - meaning, when there’s adequate amounts in the body, the brain is signalled to stop making them, and vice versa (AKA a ‘feedback loop’). T3 is considered the ‘active’ hormone, which is derived from T4, however T4 also exerts physiological effects (Mahmoodianfard et al., 2015; Razvi et al., 2018). There is also another hormone, called reverse T3 (rT3), which is an inactive form of T3. rT3 under normal conditions should be excreted quickly in the body, however sometimes the body produces more rT3 than it can excrete. This happens during times of fasting, stress, starvation, and liver disease. Increased levels of rT3 compared to T3 can cause symptoms of hypothyroidism, also creating a viscious cycle, as increased rT3 leads to a reduction in T3 formation. Hypothyroidism is where the thyroid is sluggish, and due to thyroid hormones being vital for virtually all bodily functions, there can be an exhaustive list of symptoms.
Now, there are three types of hypothyroidism.
Primary: characterised by the combination of low thyroid hormone, and elevated TSH blood levels, indicating an issue with thyroid hormone synthesis. Iodine deficiency is a major cause of primary hypothyroidism.
Secondary: characterised by low TSH and low thyroid hormones, indicating an issue with the pituitary gland.
Cellular or functional: characterised by normal blood thyroid hormones and TSH blood levels, combined with low functional thyroid activity - defined by a low basal metabolic rate and rT3 levels.
Furthermore, Hashimoto’s thyroiditis is an autoimmune hypothyroid condition. The immune system is triggered and causes an infiltration of white blood cells into the thyroid, trying to destroy it. This leads to the destruction of follicles, fibrosis, impaired T4 production, and the gradual development of hypothyroidism. This can be differentiated to the other types of hypothyroidism by measuring the amount of thyroid antibodies in the blood, being TPO and TgAB.
symptoms
The severity of symptoms depend on the severity of deficiency. Symptoms include (remember when I said exhaustive list!):
Central nervous system: low mental energy, apathy, depression, fatigue, psychotic thoughts, forgetfulness, poor concetration, headaches, decreased sweating.
Musculoskeletal: muscle weakness, cramps, delayed relaxation and reflexes, myalgia, athralgia, intolerance to cold, carpal tunnel syndrome, oedema.
Cardiovascular: bradycardia, diastolic hypertension, hyperlipidaemia, ascites, poor circulation (leading to cold extremities), increase in homocysteine.
Hematological: iron deficiency.
Respiratory: shortness of breath.
Gastrointestinal: reduced appetite, constipation, sluggish bowel transit time, flatulence, bloating.
Ear, nose and throat: hearing loss, hoarseness, puffy eyes, enlarged tongue, goitre, sore throat.
Immune: recurrent infections.
Genitourinary: impaired kidney function.
Female reproductive: low libido, infertility, menstrual irregularities, mehorrhagia, galactorrhoea, hyperprolactinaemia, fibrocystic breast disease.
Male reproductive: low libido, infertility, impotence, hyperprolactinaemia.
Integumentary: dry skin, dry mucus membranes (mouth, vagina, anus), coarse facial features, brittle and course hair and nails, hair loss, thin brittle nails, thin eyebrows.
General: fat accumulation, difficulty losing weight, puffy appearance.
causes of hypothyroid
Now, this is where naturopathy may differ to allopathic medicine, as we seek the underlying cause, rather than treating symptomatically. There can be so many implicating factors when treating the thyroid, so it is important to take a holistic case to determine the contributing factors. These may include:
Malnutrition.
Studies found severe selenium deficiencies are associated with impaired thyroid hormone synthesis, and destruction of thyroid follicles (Mahmoodianfard et al., 2015).
Studies have found zinc deficiencies lead to reduced T4 and T3 levels (Mahmoodianfard et al., 2015)
Iodine deficiencies, and also excess, is associated with hypothyroidism (Hechtman, 2012).
Environmental: radiation exposure, environmental toxins such as polybrominated and polychlorinated biphenyls and resorcinol, chemical overload, cadmium excess, food additives, herbicides, pesticides, hair dyes, stress, depression, inadequate rest and relaxation.
Iatrogenic: radioactive iodine therapy, medical radiation exposure, thyroidectomy, medication (amiodarone, thalidomide, betaroxine, lithium carbonate, stavudine, aminoglutethimide).
Pituitary: pituitary tumour, hypopituitarism, pituitary surgery, history of head trauma.
Gastrointestinal: leaky gut - caused by food allergies and sensitivities, alcohol intake, NSAIDs, corticosteroids; imbalances in the microflora (AKA dysbiosis), poor digestion and elimination
Hypothalamic: hypothalamic masses, hypothalamic radiation or surgery, hypothalamic dysfunction (as seen in sarcoidoisis, haemochromatosis).
Illness: acute viral, bacterial and fungal infections, or chronic low grade infections.
Pregnancy: there is a link between post-partum and hypothyroidism.
Age: associated with age related hyporthyoidism.
Autoimmune: such as hashimoto’s thyroiditis, previous graves disease, postpartum thyroiditis, downs syndrome, family history of an autoimmune disease, multiple sclerosis, turners syndome.
complications
Obesity.
Heart failure: Thyroid hormones have both indirect and direct effects on the cardiovascular system, with subclinical thyroid dysfunction being associated with a 20-80% increase in adverse cardiovascular events (Razvi et al., 2018). Thyroid hormones assist with cardiac contractility, heart rate, tissue tone, and have a cardioprotective effect (Ravzi et al., 2018).
what can you do about it?
Get your thyroid hormones tested - this includes your TSH, T3, T4, rT3, and antibodies.
Test your iron levels, as it is associated with hypothyroid, and low levels can be a serious condition.
Test your basal metabolic temperature - there are a few rules for this though, to achieve optimal results. The first one is you must have had a minimum of 6 hours of solid, unbroken and restful sleep. You also have to take your temperature at the same time each morning before any activity or eating. You should also document any illness, emotional distress, nightmares, dreams, alochol, or excessive caffeine consumption the day prior, as this may also affect your reading. And test your temperature for a few weeks, so you can see a pattern, if any.
Increase iodine rich foods, such as kelp, seaweed, and celtic sea salt. *Again, it is important to test your iodine prior to doing this.
Increase antioxidants, due to the increased amount of oxidative stress within the thyroid gland. Antioxidants include nuts and seeds, berries, fruits and vegetables, various teas.
Increase bitter foods to support the liver, in turn supporting the conversion of T4 to T3. Bitter foods include rocket, endive, radish, broccoli sprouts, and lemon.
The fuss about avoiding goitrogens? Eh, I don’t really care for this advice which is commonly thrown around. This is because large amounts would have to be consumed. AND cooking destroys goitrogens. So, you can still have your broccoli, brussel sprouts, and cauliflowers - just as long as you cook them first :)
Exercise 20-30 minutes per day. This has been shown to promote the secretion of TSH.
Reduce your environmental toxin exposure: Choose organic where possible, replace household cleaners and personal cares with natural alternatives, wear appropriate protection when using and being around chemicals, filter your drinking and shower water, stop smoking, swap your plastic bottles and containers for metal, glass, or beeswax, swap your cooking materials to stainless steel.
If it is autoimmune in nature, consider following an autoimmune protocol diet. I will do a blog post on this later, so stay tuned.
what can a naturopath do about it?
Naturopaths will work with you, and take an in-depth and holistic case. Treatment is aimed at normalising thyroid function, in turn, leading to a reduction of symptoms. Naturopaths will ensure relevant testing is carried out to determine the overall function of the thyroid gland. This could include TSH, T3, T4, rT3, antibodies, and scans as needed. Cofactors including zinc, selenium, magnesium, and iodine may also be indicated. If autoimmunity is found (as seen in hashimotos), the source of autoimmunity will be investigated. Common investigations include allergies, food intolerances, dysbiosis, and leaky gut. Naturopaths will assess the diet, to determine any nutritional deficiencies or excesses. Naturopaths will also assess environmental influences, such as your levels of stress, toxin exposure, and also geographical manifestations of disease. Furthermore, naturopaths will also assess the health of various systems, which may be contributing to your presentation.
key nutrients
Several micronutrients such as zinc and selenium have important roles in thyroid hormone metabolism. Zinc is involved in the synthesis and action of the thyroid hormones, as it is essential for the conversion of T4 to T3, binding of T3 to specific tissues, and the formation and action of TRH. Selenium is the thyroids main antioxidant, and thus the gland requires a high content of selenium. Selenium is also required for thyroid hormone synthesis and metabolism, because just like zinc, it is essential for the conversion of T4 to T3 (Mahmoodianfard et al., 2015).
Zinc sources include seafood, especially oysters!, beef, oatmeal, chicken, liver, spinach, nuts and seeds
Selenium sources include brazil nuts.
Iodine is an essential component of T3 and T4 hormones, and is required for human growth and development throughout the body. Iodine is added to an amino acid, tyrosine, forming the thyroid hormones. Furthermore, the physical manifestation of a goitre, commonly seen in hypothyroidism, is associated with iodine deficiency. Iodine deficiency is common in Australia - however it is important to assess your levels before supplementation, as too much iodine can also cause hypothyroidism. I know, confusing huh! This can be easily tested using a urine sample.
Iodine sources include sea vegetables (kelp, nori, wakame, kombu), seafood (mackerel, cod), iodised salt, spinach, garlic, watercress, artichokes, egg yolks, pineapple, and citrus fruits.
Copper is another cofactor of thyroid synthesis.
Copper sources include liver, organ meats, eggs, yeast, beans, nuts and seeds.
Low iron is a complicating factor in hypothyroid, and should be checked.
Iron sources include red meats, dark green leafy vegetables, nuts and seeds. Iron absorption from plant sources aren’t easily absorbed, so it is best to couple with foods rich in vitamin C - such as tomatoes, broccoli, capsicum, and citrus fruits.
B vitamins to support the mitochondrial function, which is impaired in conditions of low thyroid hormone activity.
Protein!! In particular, tyrosine, which is the direct precursor of T3 and T4.
Antioxidants, due to the increased levels of oxidative stress. Key antioxidants include vitamin C and E.
key herbs
Herbs specific to the thyroid include:
Bacopa monniera: increases T4 serum concentrations in mice models (Kar et al., 2002), and has other desirable actions, particularly in the nervous system, being cognition enhancing, adaptogen, and nervine tonic.
Fucus vesiculosus: contains high amounts of iodine, and has traditional use in treating goitres.
Coleus forskohlii: the main constituent, forskolin, stimulates the thyroid to produce thyroid hormones.
Withania somnifera: stimulates thyroid function to produce hormones, and also has desirable actions when treating the effects of stress and fatigue.
Gentiana lutea: beneficial when supporting the gastrointestinal system, to improve digestion and elimination, and reduce sugar cravings.
Vitex agnus castus: has a main effect on the pituitary gland, which may be impaired in hypothyroidism. It also is beneficial in those experiencing menstrual disturbances and infertility.
references
Hechtman, L. (2012). Clinical Naturopathic Medicine. Elsevier: Sydney, Australia
Jancic, S. A., & Stosic, B. Z. (2014). Cadmium Effects on the Thyroid Gland. Endocrine Disrupters, 391–425. doi:10.1016/b978-0-12-800095-3.00014-6
Kar A. (2002). Relative efficacy of three medicinal plant extracts in the alteration of thyroid hormone concentration in male mice. Journal of Ethnopharmacology, 81(2), 281-5. Retrieved from https://www.ncbi.nlm.nih.gov/pubmed/?term=(bacopa%5BTitle%2FAbstract%5D)+AND+thyroid%5BTitle%2FAbstract%5D.
Mahmoodianfard, S., Vafa, M., Golgiri, F., Khoshniat, M., Gohari, M., Solati, Z., & Djalali, M. (2015). Effects of Zinc and Selenium Supplementation on Thyroid Function in Overweight and Obese Hypothyroid Female Patients: A Randomized Double-Blind Controlled Trial. Journal of the American College of Nutrition, 34(5), 391–399. doi:10.1080/07315724.2014.926161
Razci, S et al. (2018). Thyroid hormones and cardiovascular function and diseases. Journal of the American College of Cardiology, 71(16). DOI:10.1016/j.jacc.2018.02.045