What’s behind low thyroid function?

Why do nearly 50% of Americans [1] have hypothyroidism according to European endocrinologists?  Known causes for hypothyroidism are autoimmune Hashimoto’s thyroiditis, radioactive iodine ablation or thyroid removal surgery (for Grave’s hyperthyroid state), iodine deficiency (rare in the U.S.), congenital hypothyroidism, or low pituitary or low hypothalamus function

But there are the more subtle contributors to low thyroid function to be aware of:

  • Xenobiotics/xenoestrogens: environmental chemicals which mimic and disrupt thyroid hormone metabolism and function. They are from plastics, pesticides, self-care products, and prescription medications (examples are synthetic estrogens, [2] lithium, interferon-alpha, amiodarone, thalidomide, etc.)
  • Sex steroid hormones [3] (estrogen, testosterone, progesterone, etc.) can interfere with thyroid hormone function
  • Emotional stress: down-regulates the HPA (hypothalamic-pituitary-adrenal) hormone cascade, including thyroid hormone; [4] inhibits the conversion of T4 to the more active T3 hormone due to low levels of the stress hormone cortisol [5] thyroid receptors are 50% less responsive to thyroid hormone supplementation in the face of low cortisol; [6] A 1994 study of refugees from East Germany who experienced chronic stress were found to have a very high rate of hypothyroidism. [7]
  • Adrenaline that is produced due to critical illness lowers thyroid hormone. [8]
  • Hyperglycemia and metabolic syndrome is much more prevalent in hypothyroidism [9] [10] and is thought to suppress thyroid hormone.
  • Heavy metals such as mercury [11] [12] have been shown to lower thyroid function
  • Chronic gut inflammation: food allergies such as gluten, the protein found in wheat, barley, rye, and their derivatives add to the autoimmune condition of Hashimoto’s thyroiditis. Gluten sensitivity (“allergy”) affects an estimated 35% percent of the general population.
  • Suboptimal nutrition furthers thyroid dysfunction: iodine, B vitamins, vitamin A, vitamin D, omega-3 fatty acids, selenium, and zinc can easily be lacking in the diet.

Peak Thyroid Support

The thyroid’s main job is to make hormones that regulate the heart, brain, lungs, liver, kidneys, muscles and every other organ and tissue. But to function properly, it needs an adequate supply of iodine — something that gets harder to metabolize with age. That’s why… MORE⟩⟩


Why your physician can easily miss low thyroid hormone function

Want to know why the diagnosis of low thyroid state is so commonly missed? The main problem is our over-reliance on thyroid blood tests. It is true that the amount of your thyroid hormones is accurately measurable with standard tests TSH, free T3 and free T4. However, these do not measure your thyroid function per se. This may explain the disconnect for many of you who have been feeling low in thyroid hormone yet your doctor says your thyroid blood tests are fine.

Let me share with you more detailed reasons why standard thyroid blood tests may not reveal low thyroid function:

  1. There can be decreased uptake of thyroid hormone by the target cells of target tissues in thyroid deficiency; and since thyroid hormone works inside the cells, the blood levels of TSH, T3 and T4 should not be expected to reflect what is happening inside the cells where their function is. Furthermore, there is reduced lymphatic drainage associated with hypothyroidism, resulting in the accumulation of waste products in the connective tissues, including especially muco-polysaccharides (sugars) that present a barrier against thyroid hormone getting to the target cells.
  2. There can be decreased conversion of T4 into T3 (the biologically active one) in low thyroid function
  3. There is decreased clearance of thyroid hormone from the blood associated with thyroid deficiency, making the blood values deceptively higher than they otherwise would be.
  4. Hypothyroidism is associated with a reduced blood volume and constriction of blood vessels, which causes T3 and T4 levels to be higher than they otherwise would be.
  5. Hormones vary tremendously during the day, and these blood tests are only a snapshot in time. Stress, in particular, will increase many hormones.
  6. The TSH test, which is touted to be the best test for thyroid deficiency, is not sensitive enough. It will only be elevated in severe primary hypothyroidism, and will not be elevated at all in secondary (pituitary) hypothyroidism.
  7. And finally, the laboratory reference ranges are taken from a basically sick population, replete with all sorts of undiagnosed and untreated endocrine deficiencies, poor nutrition and other health issues. They do not represent values for optimal health.

Thyroid function self-test

The European endocrinologists referred to in my previous article learned to identify thyroid deficiency without blood tests. Furthermore, with physiological replacement doses their patients found relief of symptoms and illnesses as discussed in my previous article. Let me share with you this simple self-test.

Start with a simple basal body temperature test you can do at home. Use a thermometer to check your axillary (armpit) temperature while still lying in bed for 10 minutes first thing in the morning before you get out of bed. Check at least three morning readings. If your temperature is consistently below the range of 97.8 – 98.2 °F and you have several symptoms, then you can be 90% certain you have low thyroid hormone function. For menstruating women it is best to check on days 2, 3, and 4 of the menstrual cycle.

Now if you match an abnormally low basal body temperature with several of the symptoms, then you are suffering from low thyroid function and deserve treatment for the problem.

[1] Barnes, Broda O: Solved: The Riddle of Heart Attacks, Robinson Press, Fort Collins, CO, 1976
[2] Arafah BM. Increased need for thyroxine in women with hypothyroidism during estrogen therapy. N Engl J Med. 2001 Jun 7;344(23):1743-9.
[3] Tahboub R, Arafah BM. Sex steroids and the thyroid. Best Pract Res Clin Endocrinol Metab. 2009 Dec;23(6):769-80.
[4] Sapolsky, R. M.; Krey, L. C.; McEwen, B. S. (1986). “The Neuroendocrinology of Stress and Aging: The Glucocorticoid Cascade Hypothesis”. Endocrine Reviews 7 (3): 284–301
[5] Ongphiphadhanakul, B; Fang, SL; Tang, KT; Patwardhan, NA; Braverman, LE (1994). “Tumor necrosis factor-alpha decreases thyrotropin-induced 5′-deiodinase activity in FRTL-5 thyroid cells”. European journal of endocrinology 130 (5): 502–7.
[6] James L. Wilson, N.D., D.C. Ph.D. Lecture in fellowship training Module I of the American Academy of Anti-aging Medicine (A4M).
[7] Bauer, M; Priebe, S; Kürten, I; Gräf, KJ; Baumgartner, A (1994). “Psychological and endocrine abnormalities in refugees from East Germany: Part I. Prolonged stress, psychopathology, and hypothalamic-pituitary-thyroid axis activity”. Psychiatry Research 51 (1): 61–73.
[8] Dünser MW, Hasibeder WR. Sympathetic overstimulation during critical illness: adverse effects of adrenergic stress. J Intensive Care Med. 2009 Sep-Oct;24(5):293-316.
[9] Kota SK, Meher LK, Krishna S, Modi K. Hypothyroidism in metabolic syndrome. Indian J Endocrinol Metab. 2012 Dec;16(Suppl 2):S332-3.
[10] Pacifico L, Anania C, Ferraro F, Andreoli GM, Chiesa C. Thyroid function in childhood obesity and metabolic comorbidity. Clin Chim Acta. 2012 Feb 18;413(3-4):396-405.
[11] Chen A, Kim SS, Chung E, Dietrich KN.Thyroid hormones in relation to lead, mercury, and cadmium exposure in the National Health and Nutrition Examination Survey, 2007-2008. Environ Health Perspect. 2013 Feb;121(2):181-6.
[12] Yorita Christensen KL. Metals in blood and urine, and thyroid function among adults in the United States 2007-2008. Int J Hyg Environ Health. 2012 Oct 5. pii: S1438-4639(12)00108-3.

Dr. Michael Cutler

By Dr. Michael Cutler

Dr. Michael Cutler is a graduate of Tulane University School of Medicine and is a board-certified family physician with more than 20 years of experience. He serves as a medical liaison to alternative and traditional practicing physicians. His practice focuses on an integrative solution to health problems. Dr. Cutler is a sought-after speaker and lecturer on experiencing optimum health through natural medicines and founder of the original Easy Health Options™ newsletter — an advisory on natural healing therapies and nutrients. His current practice is San Diego Integrative Medicine, near San Diego, California.