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10 Signs You Have an Underactive Thyroid

Constantly sleepy? Can't lose weight? Does your brain feel like it's in a fog? You may be one of the millions of Americans suffering a chronic, undiagnosed health condition.
Thyroid exam.jpg

It's called hypothyroidism, and it's a condition in which your metabolism-running thyroid gland isn't running at its best. It's sluggish, actually, which is exactly how you might feel!

Some thyroid 101 background: Your thyroid gland is the butterfly-shaped gland at the base of your neck that secretes two all-important hormones that control major bodily functions (including how you use energy, regulate body temperature, and digest food) and organs (including the heart, brain, liver, kidneys and skin). But with hypothyroidism, your body can have normal to low thyroxine hormone levels and elevated thyroid stimulating hormone (TSH) levels. These high TSH levels are a result of an overworked pituitary gland that is trying to elevate the hormone levels in an inadequately responsive thyroid.

Hypothyroidism is more common than you would believe, and millions of people are currently hypothyroid and don't know it. (And while metabolism goes hand in hand with this condition, there are also habits people do that slow metabolism.) Because early symptoms of the disease are diverse and mimic the symptoms of everyday life, millions of cases of thyroid disease remain undiagnosed or are mistaken for other disorders. Estimates vary, but approximately 10 million Americans have this common medical condition. In fact, as many as 10 percent of women may have some degree of thyroid hormone deficiency, and 12 percent of Americans will develop a thyroid disorder in their lifetimes.

January is National Thyroid Awareness Month, so we here at Eat This, Not That! thought it would a good time to review the signs and symptoms of a sluggish thyroid. Many things can put you at risk for a sluggish thyroid, from genetic predispositions to an autoimmune disorder called Hashimoto's thyroiditis (a condition that occurs in 80 percent of those with hypothyroidism in which the immune system attacks the thyroid). Fortunately, thyroid screening is a simple blood test, and thyroid trouble can often be fixed with the right prescription. See if you can relate to any of the below items and you might also want to check out these signs you should change your diet!


You're Always Tired

Sluggish Thyroid Symptoms tired

Having trouble staying awake even after a full night's sleep? Tiredness, constant fatigue, sleepiness, and lack of energy are issues associated with many conditions, but they're strongly linked with hypothyroidism. When it comes down to it, too little thyroid hormone flowing through your blood means your cells aren't getting that "get going" signal, leading you to feel sluggish. Your hypothyroidism may have tricked you into thinking you don't have enough energy for exercise, but actually, by increasing your physical activity, you can help counter fatigue and improve energy levels.


You're Eating Healthy But Still Gaining Weight

Sluggish Thyroid Symptoms weight gain

Going up a couple of pant sizes could be caused by any of these habits that make you sick and fat, but it's also one of the top symptoms of hypothyroidism. "Patients with hypothyroidism will have a generalized slowing of their metabolism and reduction in their basal metabolic rate (or BMR)," explains Dr. Reshmi Srinath, assistant professor of Endocrinology, Diabetes and Bone Diseases at Mount Sinai.

"This can lead to changes in the way their body expends energy. With a lower metabolic rate, people may gain excess weight eating a similar diet. Some of this may be excess fat, but there may also be fluid retention." So, even if you're diligently dieting and working out, weight gained due to a thyroid issue will be difficult to lose because the extra pounds are mostly from the excess accumulation of salt and water rather than fat.


You Keep Forgetting Things

Sluggish Thyroid Symptoms forget

You know you had something to do today, but you just can't remember what it is. Sure, there's sleep deprivation, stress, and aging to blame, but your overall cognitive functioning takes a hit when your thyroid is out of whack. Too little thyroid hormone may cause forgetfulness and poor memory. Because the hormone deficiency slows everything down, neurological functions will also take a toll after some time. Do you know what else hurts your brain functioning? These salty and fatty foods.


You Have High Cholesterol Levels

Sluggish Thyroid Symptoms check up

Even though your doctor doesn't typically look for thyroid problems during your check-ups, he or she will often measure your cholesterol levels. High blood cholesterol levels can put you at risk of getting heart disease, but they also might be indicative of a thyroid problem.

According to Dr. Srinath, "Hypothyroidism causes reduced clearance of cholesterol particles, so LDL and triglycerides may be elevated in a hypothyroid patient." Looking to lower LDL levels? Try eating overnight oats. The fiber called beta-glucan in this cereal grain has been shown to reduce LDL cholesterol levels by 5 to 10 percent.


You've Lost Interest In Sex

Sluggish Thyroid Symptoms sex

Having little or no desire to get it on is a side effect of a thyroid disorder. Because of the connection between thyroid function and adrenal glands—the organs that control your "fight or flight" response as well as sexual hormones like testosterone—via the shared hypothalamus and pituitary gland regulators, low levels of thyroid hormone also result in low levels of sex hormones.

"Libido is a reflection of testosterone status," explains Dr. Srinath, "too little thyroid hormone can stimulate a pituitary hormone called prolactin, which then suppresses testosterone levels." While too little thyroid hormone could be a contributor to a low libido, the cumulative impact of other hypothyroidism symptoms, such as weight gain, depression, low energy, and body aches, certainly may also play a part. So if you've been avoiding these foods that kill your sex drive and still don't feel like romping around in the sack, there might be this health condition to blame.


You Feel Down

Sluggish Thyroid Symptoms

While it might not be a primary symptom, feeling particularly down in the dumps can be a debilitating side effect of hypothyroidism. Dr. Srinath explains that "Depression can be related to other symptoms of hypothyroidism such as fatigue, muscle weakness, lethargy, difficulty with focus and concentration." With an underactive thyroid turning many body functions down to low, it's not surprising that your mood might sink too.


Your Skin Feels Dry

Sluggish Thyroid Symptoms skin

You've bought the face creams, the masks, and the moisturizing lotions, but nothing seems to work. It turns out, dry and itchy skin can be a symptom of hypothyroidism. The change in skin texture and appearance is due to reduced circulation as a result of low thyroid function. A reduction in circulation can cause skin cells to receive one-fourth to one-fifth the normal blood supply, leaving them wrinkled and cracked. Also, a slowed metabolism (caused by too little thyroid hormone production), can reduce sweating. Without the moisture from sweating, skin can quickly become dry and flaky. If just your skin is dry, you could have eczema, but if it is compounded with brittle nails, poor wound healing, and hair loss, you should be checked by your doctor.


You're Struggling to Push It Out

Sluggish Thyroid Symptoms IBS

We know constipation is an embarrassing topic that no one likes to discuss, but if you can't boot your bowel issues, it might be time to call up your doctor. Without enough of the metabolism-controlling thyroid hormone, many of your body's functions slow down. One of these functions is the action of the digestive tract, which will start to slow down. Hypothyroidism can weaken the contraction of the muscles that line your digestive tract, causing stool to move too slowly through the intestine. If your sluggish digestive tract isn't due to hypothyroidism, consider eating a banana. The super fruit is rich in fiber to help increase stool weight, potassium to help you avoid bloating and cramping, and prebiotics to help feed good gut bacteria and improve digestion.


Your Muscles Feel Sore… All The Time

Sluggish Thyroid Symptoms sore

We know exercise is a crucial component in reaching your body goals, but it shouldn't be leaving you constantly seeking out a warm bath. If your muscles don't seem to be recovering even on your days off, this might be explained by a thyroid problem. Your thyroid gland secretes hormones that control your metabolism—the body's way of converting the food you eat into fuel.

Fewer metabolism-controlling hormones mean a slower metabolism and a disruption in how your body burns energy, which can affect how your muscles feel. To counteract these symptoms, choose low-impact exercises like elliptical-stepping or swimming and increase the consumption of fish in your diet. Fish like salmon are a good source of omega-3 fatty acids, which are known to decrease the inflammation that might be contributing to your muscle and joint pain.


You're Constantly Wearing 5 Layers

Sluggish Thyroid Symptoms cold

If you're still wearing your winter coat when it's 60 degrees and sunny, you might be suffering from hypothyroidism. It might be easy to adjust the temperature in your house or car, but patients who have hypothyroidism struggle to regulate temperature in their body. Because the thyroid gland controls your body temperature, when hypothyroidism patients' bodies make too little thyroid hormone, body temperature tends to decrease because less energy is being burned by downstream cell targets. Less energy compounded with slow metabolism equals less heat.


7 Foods to Improve Thyroid Health

foods for thyroid yogurt

Now that you know some of the signs of an underactive thyroid, you should visit your doctor and see if you should be tested for hypothyroidism. But you can also do your part by being more attentive of how and what you eat. New research shows certain foods have proven potential in helping to improve thyroid health and boost the effectiveness of your metabolism master. Here's seven of them!



foods for thyroid apples

Led Zeppelin, Black Sabbath…while you may be a heavy metal fan, your thyroid? Not so much. That's because heavy metals, mercury in particular, are chemically similar to iodine — an element the thyroid needs and readily absorbs. When metals like mercury take the place of iodine at binding sites, thyroid hormone production grinds to a halt. The good news is you can instantly detox with fruits that are rich in pectin — a gelatin-like fiber that sticks to toxic compounds in the blood and flushes them out of the body through the urine. In fact, citrus pectin increased mercury excretion in the urine by 150 percent within 24 hours of supplementation, according to one study. As a weight loss bonus, research shows pectin can limit the amount of fat your cells can absorb. You'll need about four pieces of whole fruit daily to reap the benefits. Grapefruits, oranges, and peaches are all good sources, but since most pectin is found in the fibrous pith and peel, whole apples are one of the best.



foods for thyroid seaweed

Your car runs on gasoline, and your thyroid runs on iodine. Insufficient levels of the element inhibit the production of metabolism-regulating thyroid hormones; and since your body doesn't make it, it's an essential part of your diet. That's why, since 1993, the World Health Organization has supported the iodization of table salt. But because recent health headlines have called for the radical reduction of salt intake, some people don't get enough. But you can get your daily dose without ODing on salt; there are other dietary sources of iodine, and seaweed is one of the best. Just two tablespoons of brown seaweed, or a few rolls of sushi every week will meet your need. And as you nosh on your nori, you'll be blasting fat: Scientists at Newcastle University recently discovered that a compound in seaweed called alginate can suppress the seaweed of fat in the gut. No wonder it's the one food Eat This, Not That! says you should be eating in its awesome list of 50 Weight Loss Questions Answered in 5 Words or Less!


Brazil Nuts

foods for thyroid brazil nuts

Selenium. No, it's not Latina popstar. It's the all essential "on" switch to proper thyroid function — converting T4 hormone into active T3. The essential mineral also protects the gland from inflammatory byproducts of thyroid hormone production. Many people who have a sluggish thyroid or thyroid diseases exhibit deficiencies in selenium, and studies show supplementation can help. Selenium supplementation of 80 micrograms per day — about what you'll find in just one Brazil nut — helped to reduce anti-thyroid antibodies in patients with autoimmune thyroiditis (inflammation of the gland that can make it sluggish if left untreated), one study showed. As a weight-loss bonus, the nuts are rich in L-arginine, an amino acid research shows may help blast belly fat.



foods for thyroid oysters

Shuck one for your metabolism. Heck, make it a half dozen. After all, oysters are one of the best dietary sources of zinc—a mineral that's critical, and complementary, to a healthy thyroid. In fact, the body needs enough zinc to activate production of thyroid hormone. And, in turn, we need enough thyroid hormone to absorb zinc. Any way you look at it, deficiencies are likely to result in a sluggish metabolism, and supplementing with the mineral has shown to get weight loss back on track. One study found that obese people who consumed 30 mg of zinc per day—the equivalent of just six raw oysters—had improved body mass indices, lost weight and showed improvements in blood cholesterol levels.



foods for thyroid chicken

If your thyroid were a man, he'd be a meat-and-potatoes kinda guy. That's because animal protein is brimming in amino acids, particularly tyrosine—the building block of thyroid hormone, and of dopamine — both of which are necessary for weight management. A lack of tyrosine in the diet may lead to an underactive thyroid, and a deficiency in dopamine is associated with food cravings and weight gain. You can find tyrosine in dairy and leafy greens, but poultry has the added benefit of being naturally low-fat and rich in vitamin B12—deficiencies of which are also common among people with sluggish thyroid symptoms.



foods for thyroid yogurt

Every spoonful of yogurt acts as a protective shield for your thyroid. That's because yogurt is naturally rich in vitamin D, and not getting enough of the nutrient puts you at a higher risk of obesity and thyroid diseases, research suggests. Over 90 percent of people with Hashimoto's, an autoimmune disease that's the most common cause of hypothyroidism, are deficient in D, according to one study published in the International Journal of Health Sciences. Researchers say the sunshine vitamin's immunity-boosting and anti-inflammatory properties protect the thyroid from damage. In addition to vitamin D, yogurt is also rich in probiotics that research suggests may help balance "good bacteria" in the gut that can be thrown off by thyroid disturbances.



foods for thyroid salmon

There are plenty of fish in the sea, but salmon may be the best one for your metabolism. That's because most cases of underactive thyroid are due to inflammation of the gland, and salmon boasts significant anti-inflammatory properties thanks to its rich omega-3 fatty acid content. In fact, one study that looked at the effects of weight loss and seafood consumption showed salmon to be the most effective at reducing inflammation — better than cod, fish oil, and a no-fish diet. The fishy fatty acids may also signal thyroid cells in the liver to burn more fat, a recent study published in The Journal of Nutritional Biochemistry suggests. But make sure it's wild salmon; farmed salmon is scary!


Olivia Tarantino
Olivia Tarantino is a senior editor of Eat This, Not That!, specializing in nutrition, health, and food product coverage. Read more
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