A tiny gland in your neck plays a major role in how your body runs. Pumping out the thyroid hormone, the thyroid gland targets each cell, converting food into fuel and helping you think, grow and stay healthy. Yet misconceptions persist about this hormone that travels through your blood. So, it pays to know more about the butterfly-shaped gland than its location, which is below the Adam’s apple and in front of your windpipe. Sorting fact from fiction is Edward Nicklas, MD, an endocrinologist, or hormone specialist, at Memorial Hermann Medical Group West University.
Claim: The terms hypothyroidism and hyperthyroidism can be confusing.
TRUE. They refer to two different disorders. Hypo refers to an underactive thyroid and hyper to an overactive one. If it helps you to clarify the difference, think about hyperactive children, who are overly active.
Claim: Symptoms for a hypoactive thyroid are opposite those of a hyperactive one.
FALSE. While each of these conditions has its own signs, the two also share some symptoms. In both cases, people may feel tired and weak. But an underactive thyroid tends to be linked to weight gain, sensitivity to cold and constipation, while an overactive one is linked to weight loss, sensitivity to heat, a racing heart and frequent bowel movements. “One challenge to diagnosis is that many medical conditions have symptoms that overlap with thyroid issues,” Dr. Nicklas says. “For instance, a fast heart rate and jitteriness may be due to too much caffeine or not getting enough oxygen.”
Sometimes an underactive thyroid is due to the autoimmune disease Hashimoto (or Hashimoto’s thyroiditis), and an overactive one is due to Graves’ disease. Each autoimmune conditions may cause swelling around the eyes and other parts of the body, he says. The swelling behind eyes due to Graves’ disease also may make them bulge and be irritated, as if you had sand in your eyes.
Claim: Thyroids remain balanced until you reach your mid-40s.
FALSE. While women are five to eight times more likely to have over- or underactive thyroids than men, “thyroid problems can start at any age, from newborns to the elderly,” Dr. Nicklas says. Your thyroid also may slow down or speed up—briefly or permanently—after having a baby. Anyone with a family history of thyroid imbalances also is more vulnerable to having one.
Claim: Thyroid disease causes autoimmune disorders.
FALSE. Autoimmune thyroid disease can co-exist with other autoimmune disorders, but we don’t believe it causes them. “If you have one autoimmune disorder, your chances of having another autoimmune disease are higher,” Dr. Nicklas says. Examples of other autoimmune diseases include dermatitis, lupus, or rheumatoid arthritis.
Claim: You’re more likely to get thyroid cancer if you have thyroid imbalances.
FALSE. “From what we know, a family history of thyroid cancer or a personal history of radiation treatment to the head or neck as a child or teen would be risk factors for thyroid cancer,” he says. “People can develop thyroid cancer yet have normal thyroid function.”
Claim: You can ignore an unbalanced thyroid.
FALSE. Left untended, the small thyroid gland can wreak havoc throughout the body. “Untreated thyroid issues can adversely affect the heart and can be life-threatening,” Dr. Nicklas says.
Claim: You can treat your thyroid on your own.
FALSE. Leave treatment to the professionals—and leave iodine supplements alone. “In the U.S., we get all the iodine we need through our diet,” he says. “Too much iodine can make your thyroid overactive—or shut it down.” An exception is during pregnancy, when iodine supplements are needed, as directed by your OB/GYN. You also may get irregular heartbeats, an enlarged heart, cardiovascular issues or osteoporosis, a weakening of bones from excess thyroid hormone.
Claim: You can detect thyroid problems on your own.
FALSE. Thyroid nodules are very common—and almost all are benign, Dr. Nicklas says. “You can only feel one of 10 nodules. It’s difficult even for medical professionals to palpate a thyroid.”
It would be important to let your doctor know if you have any concerns regarding your neck. “An ultrasound is the best way to assess the thyroid, but other things in the neck can cause abnormalities,” he says.
Healthcare providers can detect thyroid imbalances via blood tests. Usually, two are needed. One measures thyroid stimulating hormone (TSH), which is produced by the nearby pituitary gland. A high level suggests a sluggish thyroid as the pituitary sends TSH to aid an underperforming thyroid. A low TSH suggests the opposite.
T-4 blood level also is important, with a low one indicating an underactive thyroid and a high one, an overactive one.
Claim: Iodine isn’t the sole treatment.
TRUE. Iodine isn’t a treatment for an underactive thyroid. For that condition, your doctor will prescribe a daily thyroid hormone replacement to raise levels.
“Food interferes with its absorption so it should be taken on an empty stomach, at least an hour before eating,” Dr. Nicklas says. “Generic pills work just fine, but your blood levels may change if you switch from brand to generic or vice versa, so you should have your blood levels tested 6 weeks after switching to make sure you’re on the right dose.”
If your thyroid is overactive, your doctor may recommend surgically removing the gland, or slowing it with thionamide pills or radioactive iodine treatment. Usually, one round of radioactive iodine fixes levels within 3 months.
Claim: You can enhance weight loss by taking more of your thyroid replacement drug.
TRUE. But the risks to your overall health are not worth it. You should consult the prescribing provider before making any changes to your thyroid replacement dose. “The main concern would be heart abnormalities from taking too much,” Dr. Nicklas says. “You also may thin bones, which can cause bone breaks.” In addition, you may worsen your quality of life and mental health since too much thyroid hormone may spark anxiety, fatigue and weakness. To learn more about endocrinologists at Memorial Hermann, click here.