Vail Daily health column: Your thyroid, your health
Did you know every cell in your body depends on thyroid hormones for regulation of metabolism? If your thyroid is not functioning properly, then it may produce too much thyroid hormone, causing hyperthyroidism and symptoms of increased metabolism (i.e., anxiety, frequent bowel movements, bulging eyes, irregular heartbeat, weight loss despite increased appetite). Or it may produce too little thyroid hormone, causing hypothyroidism and symptoms of slow metabolism (i.e., fatigue, sensitivity to cold, dry skin, constipation, unexplained weight gain, depression, infertility, muscle/joint pain).
THE THYROID GLAND, TSH/T4/T3
The thyroid is a small, butterfly-shaped gland at the base of your neck. It is often compared to a car engine because it controls the pace at which your body operates. Just as an engine produces the necessary amount of energy for a car to move a certain speed, the thyroid manufactures and releases enough thyroid hormone for your cells to function at a certain rate.
The main fuel needed by your thyroid to produce thyroid hormones is iodine. The thyroid hormone T4 requires four iodine atoms. T4 is mostly inactive and stored in the thyroid until needed. T4 is released into the bloodstream and converted to active T3 by the loss of one iodine atom.
Unfortunately, many Americans are iodine deficient due to inadequate dietary sources and substances that compete with iodine such as fluoride, bromide and chlorine. Low iodine levels are also tied to thyroid nodules, fibrocystic breasts, ovarian cysts, uterine fibroids and frequent infections.
Thyroid stimulating hormone from the pituitary gland in your brain increases when your body needs more energy, signaling your thyroid to release more T4. A high TSH usually indicates an under functioning thyroid because it’s stimulating the thyroid to make more T4 (hypothyroidism). A low TSH usually indicates an overactive thyroid because it’s asking the thyroid to decrease the amount of T4.
Hypothyroidism is much more common than hyperthyroidism. Women are five to eight times more likely than men to have hypothyroidism and it is often undiagnosed and, when diagnosed, it is often undertreated. It is estimated that nearly 13 million Americans have undiagnosed hypothyroidism.
Older age, family history, radiation, iodine deficiency, lack of companion nutrients (selenium, zinc, magnesium, vitamin C), gluten sensitivity and autoimmune disease are some causes of hypothyroidism.
Untreated hypothyroidism can contribute to hypertension, high cholesterol, heart disease, infertility, cognitive impairment and neuromuscular dysfunction. Complete thyroid testing should include TSH, T4, T3 and thyroid antibodies. Other thyroid tests such as reverse T3 can be considered depending on your history and symptoms. If the underlying cause of hypothyroidism can be determined and addressed, lifelong need for hormone replacement might not be necessary.
Thyroid hormone replacement
Many options exist for thyroid hormone replacement. The most common is to replace T4 in the form of synthetic levothyroxine (Synthroid). For some, this will work fine, as long as your body is able to convert the inactive T4 to active T3. For others who are poor T4 to T3 converters or who remain symptomatic despite “normal” labs, a combination of synthetic T4 and T3, or natural T4/T3 can be used.
Pregnant women and those on certain types of antidepressants may require higher doses of thyroid replacement. A thorough history, exam and appropriate labwork are necessary to diagnosis and treat thyroid conditions. Treating the underlying cause of thyroid dysfunction and optimizing thyroid levels may require adjusting doses over a period of time until you feel better.
The information in this article does not replace professional medical diagnosis, treatment or advice. We strongly advise that you seek professional counsel before making any health decision. Susan Lan, a Doctor of Osteopathy, practices holistic integrative medicine and traditional osteopathic manipulation at Vail Osteopathy, located at The Riverwalk at Edwards. She can be reached at 970-306-1448 or online at http://www.VailOsteopathy.com and http://www.facebook.com/VailOsteopathy.