Thyroid Health Essential to Metabolism

Thyroid plays an essential role in your body’s metabolism
By Brian Phillips, MD 

Unless you’re one of the 20 million Americans who has some type of thyroid condition – and up to 60 percent of those who have a condition aren’t even aware they do – chances are you’re not too familiar with the relatively small, hormone-producing gland that influences every cell, tissue and organ in your body. 

Located in the middle of the lower neck, the butterfly-shaped thyroid helps regulate the body’s metabolism—the rate at which the body produces energy from nutrients and oxygen. It affects critical body functions, such as energy level and heart rate. The thyroid’s job is to make thyroid hormones, which are secreted into the blood and then carried to every tissue in the body. Thyroid hormone helps the body use energy, stay warm and keep the brain, muscles and other organs working as they should. 

Thyroid conditions are often autoimmune.  They sometimes can run in families but otherwise the triggers are not always clear. Women are five to eight times more likely than men to have thyroid problems. One woman in eight will develop a thyroid disorder during her lifetime, often during or following pregnancy.  

Hypothyroidism
The most common thyroid condition by far is hypothyroidism – an underactive thyroid – accounting for 90 percent of thyroid imbalances. Symptoms can include a feeling of coldness, fatigue, depression, forgetfulness, and unexplained weight gain.  With hypothyroidism, the cells in the thyroid gland aren’t making enough thyroid hormone to keep the body functioning normally.  When thyroid hormone levels are too low, the body’s cells can’t get enough thyroid hormone and the body’s processes start slowing down. As the body slows, you may notice that you feel colder and tire more easily. 

Because symptoms can range from barely noticeable to severe, the only way to know for sure whether you have hypothyroidism is a simple blood test measuring your thyroid-stimulating hormone or TSH levels.  It is treated by replacing the amount of hormone your thyroid can’t produce with a once-a-day thyroid hormone replacement pill. Hypothyroidism can’t be cured. But in almost every patient, hypothyroidism can be completely controlled. 

The most common cause of hypothyroidism is an autoimmune condition called Hashimoto's thyroiditis, where the body makes antibodies that destroy parts of the thyroid gland.

Hyperthyroidism
In exactly the opposite direction, hyperthyroidism – an overactive thyroid – is a far less prevalent condition where the thyroid is producing too much of its hormone in the body.  Symptoms can include a feeling of hotness, irritability, nervousness, shakiness, hand tremors, unexplained weight loss and sleep disturbances. The most common cause of this hormone overproduction is another condition known as Graves’ disease. Graves’ is caused by antibodies in the blood that turn on the thyroid and cause it to grow and secrete too much thyroid hormone. 

As with hypothyroidism, the hyper version is diagnosed through a simple blood test.  Several treatments for hyperthyroidism exist. The best approach depends on the patient’s age, physical condition, personal preference and the severity of the disorder. Possible treatments include taking a radioactive iodine pill which is absorbed by your thyroid gland, causing the gland to shrink. Symptoms usually subside within several months.  Daily anti-thyroid medications also are available which gradually reduce symptoms by preventing the thyroid from producing excess amounts of hormones. Surgical removal of the thyroid was once a relatively common option, but has been largely replaced by non-invasive alternatives. 

Other thyroid conditions include the growth of nodules – usually benign – on the gland itself.  In some cases, those nodules may need a biopsy, and less often may need removal.  The most common types of thyroid cancer are not very aggressive, are very treatable and often curable. Overall, most thyroid diseases are life-long conditions that can be managed with medical attention. 

Brian Phillips, MD, is an endocrinologist with Berkshire Medical Center