Monitor your thyroid function as you age

<p>How much do you know about your thyroid gland? See if you can tell which of these facts are true:</p><p>Every cell of the body depends on the thyroid gland to regulate metabolism.</p><p>The function of the thyroid gland is to process iodine into hormones.</p><p>The thyroid gland is first formed at the base of a developing baby’s tongue, normally migrating to the front of the neck before birth.</p><p>Thyroid cancer is a relatively common malignancy, but rarely fatal. </p><p>Life is not sustainable without the thyroid gland.</p><p>All but one of these facts about the essential thyroid is actually true. Read on.</p><p>The thyroid gland is shaped like a butterfly with two lobes connected in the middle. This gland is usually located in the neck, just below the “Adam’s apple.” Rarely, during development inside the womb, the migration from its origin at the base of the tongue will not go as nature intends, so the thyroid may occasionally end up in the throat or even down inside the chest. But it can still function, wherever it lands.</p><p>The incidence of thyroid dysfunction increases with age, so it is often wise to screen for thyroid disorders. Remembering to monitor this metabolic regulator can help you maintain your good health and sense of well-being well into your golden years.</p><p>Production of thyroid hormones are regulated by an elegant feedback loop that involves two other glands: the hypothalamus, nestled deep within our brain, and the pituitary, which sits at the base of the brain. The hypothalamus secretes TRH (TSH Releasing Hormone), which communicates with the pituitary gland, telling it to release TSH (Thyroid Stimulating Hormone). </p><p>When stimulated by the pituitary’s TSH, the thyroid gland absorbs iodine, combining it with an amino acid to release two essential hormones, T3 and T4. When these enter the bloodstream they control the metabolism of every single cell in the body, converting oxygen and calories to pure energy. Thus, our body’s metabolism is completely dependent on the thyroid gland.</p><p>This whole cascade is a feedback loop controlled by the amount of T3 and T4 circulating in the body. When there is plenty, the hypothalamus and pituitary turn the system down. When more is needed, the system turns itself back up again.</p><p>As you might imagine, with so many different glands involved, there are plenty of reasons for our metabolic regulation to go wrong. A problem with any one of these regulators can affect the thyroid — injuries, infections, inflammation, pregnancy, or cancers. In addition, many of the symptoms of thyroid disorder can be misdiagnosed as menopause, depression, heart disease or other isolated conditions.</p><p>When the production of thyroid hormones is either too much or too little, our health is significantly affected. </p><p>Too much (hyperthyroidism) may cause irritability, heart palpitations, high blood pressure, insomnia, weight loss, or muscle weakness. While taking thyroid supplements to increase energy levels and to lose weight may sound good, these supplements create more problems than they solve. Increasing the body’s metabolism artificially with thyroid hormones can cause heart failure, cardiac arrhythmias, eye problems and severe bone loss.</p><p>Too little (hypothyroidism) causes symptoms that include intolerance to cold, weight gain, depression, weakness, dry skin, muscle cramps, constipation, or memory loss. </p><p>Both hyper- and hypothyroidism can cause fatigue, irregular menstrual periods, irritability, or hair loss. Your physician can test for these imbalances with a simple blood test that evaluates the level of TSH. Remember the feedback loop? If the TSH is high, the thyroid is being asked to produce more hormones, so there must be a deficiency. If the TSH is low, there may be too much T3 and T4 in circulation.</p><p>Like most glands in our body, the thyroid can develop cancer. This is a relatively common occurrence, but is rarely fatal. Any abnormal masses in the gland should be evaluated if suspicious for malignancy. Occasionally the whole thyroid gland must be removed, but the essential hormones it produces can easily be replaced with oral supplements to maintain the body’s metabolism. </p><p>For a more complete description of the thyroid and symptoms of thyroid disorders, go to www.endocrineweb.com/thyroid.html</p><p>Dr. Stacey Kerr, a longtime Sonoma County family physician, graduated from UC Davis Medical School and is certified in her specialty by the American Board of Family Medicine. Her columns are not intended as a substitute for hands-on medical advice or treatment. Consult your health care provider before adhering to any recommendations in this column. E-mail comments to drkerr@the-doctors-inn.com.</p>