ICYMI: Your thyroid is kind of a big deal. The butterfly-shaped gland at the base of your neck takes iodine, found in many foods, and converts it into thyroid hormones (TH). And that’s important because “every tissue and every cell is sensitive to TH,” says endocrinologist Antonio Bianco, M.D., Ph.D., a professor of medicine at Rush University Medical Center in Chicago. TH impacts everything from metabolism to cognitive function to body temperate to energy levels. But for one in eight women, this essential regulator goes on the fritz, producing too much—or too little TH, according to the American Thyroid Association.
While experts aren’t sure exactly what makes your thyroid go haywire (though genetics, autoimmune diseases, and stress may play a role), at least 30 million Americans—the vast majority of them women—suffer from a thyroid disorder, and half of them are undiagnosed, according to The American Association of Clinical Endocrinologists. That’s because it’s easy to brush off common symptoms as signs of everyday stress or aging. (Kick-start your new, healthy routine with Women’s Health’s 12-Week Head-to-Toe Transformation!)
If you answer yes to more than one of the questions below, ask your family doctor to run a simple blood test to check your hormone levels. Your doc may be able to suggest treatment options that can help your thyroid get back on track.
1. Do You Feel Exhausted, No Matter How Much Sleep You Get?
TH stimulates the brain, so when too little thyroid hormone—a condition called hypothyroidism—is coursing through your veins, body functions slow down, leaving you feeling sluggish and with zero energy, says Bianco. You mood may be in the basement as well, since it’s thought that the production of too little thyroid hormone can lower levels of serotonin, a feel-good neurotransmitter in the brain. And you may start forgetting where your keys are, since your hippocampus (your brain’s memory hub) needs TH to function, too.
2. Alternately, Do You Feel Like You Just Chugged a Triple-Shot Venti?
Feeling wired and jittery can signal that your thyroid is off-kilter in the other direction, pumping out too much of the hormone, says Bianco.
3. Do Your Jeans Fit Differently?
An underactive thyroid slows your metabolism to a snail’s pace, says Bianco. And when your body converts fewer calories into energy it can lead to weight gain. And—insult, meet injury—you may also retain fluids since your kidneys might also slow down how quickly they excrete water. But if your thyroid is operating at warp-speed, you might lose weight, even if you’re still scarfing down the same amount of food.
4. Got Period Problems?
Longer, irregular periods with a heavier flow can be a sign that TH is in short supply, says Bianco. Hypothyroidism is linked to high levels of prolactin, a hormone that’s primarily responsible for stimulating the production of breast milk after childbirth, but also regulates the menstrual cycle. With hyperthyroidism, soaring hormones can make your cycle longer (so your periods are farther apart but shorter) and lighter.
5. Do You Feel All Aflutter?
You may notice heart palpitations—literally, your heart skipping a beat—if an overload of TH causes the heart to amp up its usual pace as your tissues are demanding more oxygen-rich blood. “It may also directly affect the heart muscle,” says Bianco. You may notice the feeling in your chest or other pulse points (your throat or wrist).
6. Are You Stripping Down to Your Skivvies—or Adding a Layer?
When your thyroid is overactive, the increase in your metabolism can leave you sweating, says Bianco. When it’s underactive, your body tries to conserve heat by limiting blood flow to the skin, which can leave you chilly even on a warm day.
7. Have Your Bathroom Habits Changed?
Yes, we mean pooping. Hypothyroidism can slow down the muscles in the gut that contract to move its contents through the bowel, leaving you constipated, says Bianco. On the reverse end of the spectrum, an overactive thyroid can cause the opposite to happen (ahem, diarrhea).
8. Are Your Skin and Nails Dry?
A sluggish metabolism can dial down sweating, says Bianco. Sans the extra moisture, your skin can easily become dry and flaky and your nails can become brittle.