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10 Myths About Your Thyroid

Find out what's misunderstood about this important metabolism-controlling gland.

The thyroid gets a bad rap, blamed for everything from fatigue to weight gain. And while these are common symptoms of an underactive thyroid, this important endocrine gland isn't always responsible for your negative physical symptoms. In fact, people throw around the word "thyroid" without understanding what exactly it does. Eat This, Not That! is here to clear things up.

Your thyroid is the butterfly-shaped gland in your neck that releases two important hormones (triiodothyronine and thyroxine), which regulate your body temperature, metabolism, and how you digest food. It's also in charge of vital organs such as your heart, brain, liver, kidneys, and skin.

Conditions such as hypothyroidism, hyperthyroidism, Graves disease, and Hashimoto's thyroiditis fall under the umbrella term of thyroid disease. Although an estimated 20 million Americans suffer from some kind of thyroid disease, the symptoms are hard to pin down and tend to mimic the common stressors of everyday life: fatigue, anxiety, or feeling too hot (or cold), to name a few. Since so much is still misunderstood about this metabolism-controlling body part, we're separating fact from fiction. Want to keep your thyroid functioning at its best? Check out the 25 Best Foods to Eat for Your Thyroid and Metabolism.

Myth: It's Making You Fat

Your thyroid may be a convenient scapegoat for noticeable weight gain; after all, it controls your metabolism, which affects how many calories you burn throughout the day — an underactive thyroid (hypothyroidism) means a slower metabolism, and therefore a slower rate at which your body can convert food into energy. But in reality, a slow metabolism is pretty rare. "Although the thyroid does have a role in regulating metabolism, it is one variable in a very complicated network of hormones and neurological connections," explains Dr. Eduardo Grunvald, program director at UC San Diego's Weight Management Program. "While there a minority of patients that will notice a significant weight gain with untreated hypothyroidism (and weight loss with treatment), most people have to address all the other factors that contribute to weight even when the thyroid is off." Check out our 30 Secret Reasons You've Gained Weight to see what else could be the culprit.

Other symptoms other than weight gain could also signal an issue with your thyroid: fatigue, brain fog, anxiety, and dry skin. If you're convinced you have a thyroid issue, make sure you visit a doctor to get a blood test.

Myth: Sudden Weight Loss Means You Have an Overactive Thyroid

On the flip side, an overactive thyroid (hyperthyroidism) or Graves' disease can manifest itself with symptoms of weight loss, but not always. Some people actually gain weight while their thyroid is overactive. Other symptoms of hyperthyroid include a fast heart rate, high body temperature, and difficulty sleeping.

Myth: Only Women Get Hypothyroidism

It's true that more women than men get thyroid disease, especially hypothyroidism. That's because it's an autoimmune disease, which is more common in women thanks to the presence of estrogen. But men can have thyroid problems, too. In fact, the symptoms men experience from an underactive thyroid include hair loss, constipation, fatigue, loss of sex drive, and sore muscles, among others.

Myth: You Don't Need Medication to Control Your Thyroid

If you do have a thyroid disease, treating it is more complicated than swapping your potato chips for an apple. Sure, making more healthful food choices will impact your thyroid, but it can't be treated with diet alone. If you've been diagnosed with a thyroid disease, make sure you check with your doctor to see what the best course of treatment is. Often times, it's a mix of medication, healthy diet, and exercise.

Myth: You Can't Take Thyroid Medication During Pregnancy

Pregnancy usually means giving up an exhaustive list of food and medicine for nine months: alcohol, sushi, caffeine, deli meat, aspirin, ibuprofen. Luckily, thyroid medication isn't one of them. Of course, get the go-ahead from your doctor before taking any medication while pregnant.

Myth: Only Older People Get Thyroid Disease


Thyroid issues are usually associated with people of a certain age; after all, women over 60 have a 20 percent chance of having a problem with their gland. But it's not just a senior citizen's disease. It can happen to people of all ages: especially women after pregnancy, or in their late 30s when their hormones change. Even if you're young and still notice symptoms of thyroid issues (weight gain, fatigue, depression, change in body temperature, etc.), be sure you tell your doctor.

Myth: A Gluten-free Diet Will Cure Thyroid Issues

Like we mentioned earlier, diet changes can definitely impact your thyroid for the better. But it's not a cure-all. Most thyroid disease, like Graves' disease and Hashimoto's, have a genetic component, so family history is your biggest trigger — not a diet rich in gluten. If you happen to have celiac disease as well as a thyroid issue, then, of course, banish the bread. Otherwise, thyroid disease is usually treated with medication prescribed by your doctor.

Myth: A Lump in Your Neck is Probably Thyroid Disease

Although a lump on your neck could signal an enlarged thyroid or thyroid cancer, that's not always the case. It could be a swollen lymph node, which happens when you have a cold or a sore throat. Or it could be an enlarged cyst. Have your doctor check it out to be 100 percent sure.

Myth: You Can Treat Thyroid Disease Yourself with Iodine


It's true, your thyroid uses iodine (commonly found in table salt) to function, so getting enough of it is key to a working gland. And radioactive iodine (RAI) therapy is sometimes used to treat overactive thyroid disorders or thyroid cancer. But in reality, most people get adequate amounts of iodine just in their daily diets. In fact, overdoing it on the iodine could actually cause more thyroid problems, like producing too much thyroid hormone in an attempt to process all the extra iodine. So don't go the DIY route and take iodine supplements on your own without consulting with your doctor first.

Myth: You Have to Totally Give Up Soy


Although a popular choice for plant-based protein, soy can activate your body's estrogen receptors, which may mess with your hormones. And if you're taking thyroid medication, soy could impair how it's being absorbed in the body. But this vegan protein doesn't need to be avoided entirely. Soy can be enjoyed in moderation—say, a few times a week at dinner to avoid interfering with morning medication. To blast even more fat, and live your hapiest and healthiest life, don't miss these essential 25 Food Myths That Cause Weight Gain!