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9 Signs Your Thyroid Is Making You Gain Weight

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.

Going up a couple of pant sizes could be caused by any of these 'healthy' habits secretly behind your weight gain, but it's also one of the top symptoms of hypothyroidism. Also called an underactive thyroid, hypothyroidism is a condition in which your metabolism-running thyroid gland doesn't make enough thyroid hormones to meet your body's needs.

Hypothyroidism is more common than you would believe; the metabolic disease affects 4.6% of the U.S. population and millions of people are currently hypothyroid and don't know it.

There are over a dozen common symptoms of hypothyroidism, and weight gain is one of the most prevalent.

"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, you may still gain weight if you have hypothyroidism.

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. If you've recently gained weight, it may be worth checking to see if you also have any of the following symptoms so you know it's time to see your doctor to get tested. 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!

First, some thyroid 101

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Your thyroid gland is the butterfly-shaped gland at the base of your neck. It 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.

Many things can put you at risk for hypothyroidism, 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.

Keep reading for some of the common symptoms you may experience if an underactive thyroid is behind your weight gain.

You're Always Tired

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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 can also try adding these 23 Best Foods for Energy Metabolism to your diet.

Your Muscles Feel Sore… All The Time

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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 Keep Forgetting Things

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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.

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You Have High Cholesterol Levels

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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.

See your doctor to get checked for high cholesterol levels, and when you're looking to change your diet to lower these levels, consider these 17 Foods That Lower Cholesterol.

You've Lost Interest In Sex

Young Attractive Couple Having Problem in Bed. Frustrated Man and Woman Not Talking Feeling Offended or Stubborn. Concept of Impotence. Man Have Problems.
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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

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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

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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 Having Digestive Problems

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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.

You're Constantly Wearing 5 Layers

Man sitting on the bed wrapped in a blanket feeling sick while girl hugging him and trying to help him.
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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 the temperature in their bodies. 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. One part of your hypothyroidism treatment may be changing your diet. If so, you'll want to look at these 25 Best Foods to Eat for Your Thyroid and Metabolism.

Olivia Tarantino
Olivia Tarantino is the Managing Editor of Eat This, Not That!, specializing in nutrition, health, and food product coverage. Read more about Olivia
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