Hypothyroidism

What is hypothyroidism?

Hypothyroidism occurs when your body doesn’t produce enough thyroid hormones. The thyroid is a small, butterfly-shaped gland that sits in front of your windpipe. It releases hormones that help your body regulate and use energy.

Thyroid hormones help control functions including how your heart beats and how your digestive system works. Without the right amount of thyroid hormones, your body’s natural functions begin to slow down.

Also called underactive thyroid, hypothyroidism usually affects people over the age of 60 and is more common in women than men. It may be discovered through a routine blood test or after symptoms begin.

Subclinical hypothyroidism is the name given to an early, mild form of the condition.

If you’ve recently received a hypothyroidism diagnosis, it’s important to know that treatment is considered simple, safe, and effective.

Most treatments rely on supplementing your low hormone levels with artificial hormones. These hormones will replace what your body isn’t producing on its own and help return your body’s functions to normal.

Hypothyroidism vs. hyperthyroidism

Hypothyroidism and hyperthyroidism have opposite effects. With hyperthyroidism or overactive thyroid, the thyroid gland makes too much thyroid hormone.

The greater amount of thyroid hormone causes some functions in your body to become faster, like your heart rate. You may also experience weight loss and difficulty sleeping.

Hyperthyroidism is less common than hypothyroidism. It affects around 1 percent of people ages 12 and older in the United States. Like hypothyroidism, it occurs more frequently in women and people over age 60.

Medications, radioiodine therapy, and surgery may be used to treat hyperthyroidism.

How common is hypothyroidism?

Hypothyroidism is a fairly common condition. In the United States, almost 5 percent of people ages 12 years old and up have hypothyroidism.

The disease gets more common with age. People over 60 years old experience it more frequently.

Women are more likely to have an underactive thyroid. In fact, 1 in 8 women will develop thyroid issues.

What are the signs and symptoms of hypothyroidism?

The effects of hypothyroidism on the body often vary among different people and may be difficult to identify. The severity of the condition also affects which signs and symptoms appear and when.

Early symptoms can include weight gain and fatigue. Note that these both become more common as you age, regardless of your thyroid’s health.

As a result, you may not realize that these changes are related to your thyroid until more symptoms appear. For instance, these may include skin changes associated with hypothyroidism, like scaly, rough, and dry skin and fragile nails.

In general, the most common signs and symptoms of hypothyroidism include:

fatigue
weight gain
depression
constipation
feeling cold
decreased sweating
slowed heart rate
elevated blood cholesterol
dry skin
dry, thinning hair
impaired memory
muscle weakness
muscle stiffness, aches, and tenderness
pain and stiffness in your joints

For most people, symptoms of the condition progress gradually over many years. As the thyroid slows more and more, the symptoms may become more easily identified. Of course, many of these symptoms also become more common with age in general.

Hypothyroidism symptoms in adults

Besides the most common hypothyroidism symptoms, research indicates that hypothyroidism symptoms in men may also include erectile dysfunction.

Hypothyroidism symptoms in women may additionally include:

fertility difficulties
menstrual changes, particularly irregular or heavy periods
problems during pregnancy, including anemia

It’s also possible to develop hypothyroidism during pregnancy. Symptoms will usually be similar to those of other cases of hypothyroidism.

Hypothyroidism in young people

While hypothyroidism is less common in younger people, it can still occur. The condition may cause slower development in children and early puberty in teenagers.

Babies may also be born lacking thyroid function, a condition called congenital hypothyroidism. Symptoms of hypothyroidism in infants may include:

sleeping more than usual
constipation
difficulty with feeding
delayed growth (if the condition is untreated)

In some cases, babies with hypothyroidism may show no symptoms.

Severe hypothyroidism symptoms

If hypothyroidism isn’t treated, you may develop additional symptoms:

puffy, sensitive face
hoarseness
anemia
loss of hearing

In rare cases, severe hypothyroidism may result in a myxedema coma, a life-threatening condition that requires emergency care. While the condition does not actually involve being in a coma, you may experience:

fatigue
hypothermia
low blood pressure
low heart rate

What causes hypothyroidism?

The most common causes of hypothyroidism are:

Hashimoto’s thyroiditis
radioactive iodine treatment
thyroid surgery
radiation therapy
medications
iodine deficiency

Less common causes include:

pituitary disorders
congenital disease
pregnancy
de Quervain thyroiditis

What are the risk factors of hypothyroidism?

Factors that can increase your risk of developing hypothyroidism include:

being female
being at least 60 years old
being treated with radiation therapy to your neck or chest
recently being pregnant
having a family history of thyroid disorders
having certain autoimmune conditions, such as Sjögren’s disease and type 1 diabetes

How is hypothyroidism diagnosed?

Two primary tools are used to determine whether you have hypothyroidism: a medical evaluation and blood tests.

Medical evaluation

Your doctor will complete a thorough physical exam and medical history. They’ll check for physical signs of hypothyroidism, including:

dry skin
slowed reflexes
swelling in the neck
a slower heart rate

In addition, your doctor will ask you to report any symptoms you’ve been experiencing, such as fatigue, constipation, or constantly feeling cold.

If you have a known family history of thyroid conditions, tell your doctor during this exam.

Blood tests

Blood tests are the only way to reliably confirm a diagnosis of hypothyroidism.

A thyroid-stimulating hormone (TSH) test measures how much TSH your pituitary gland is creating:

If your thyroid isn’t producing enough hormones, the pituitary gland will boost TSH to increase thyroid hormone production. The high TSH levels indicate hypothyroidism.
If you have hyperthyroidism, your TSH levels will be low, as your body is trying to stop excessive thyroid hormone production.

A thyroxine (T4) level test is also useful in diagnosing hypothyroidism. T4 is one of the hormones directly produced by your thyroid. Used together, T4 and TSH tests can help evaluate thyroid function.

Typically, if you have a low level of T4 along with a high level of TSH, you have hypothyroidism. If you have subclinical hypothyroidism, though, you may have normal T4 with a high TSH level.

Since there’s a spectrum of thyroid disease, other thyroid function tests may be necessary to properly diagnose your condition.

If your T4 test is normal, you may also receive a triiodothyronine (T3) test. Low T3 levels may indicate hypothyroidism, though again, T3 levels may be normal in subclinical hypothyroidism.

Finally, thyroid antibody tests look for antibodies in your blood to diagnose autoimmune thyroid disorders like Hashimoto’s thyroiditis.

Medical treatment

Hypothyroidism is a lifelong condition. For many people, the medication reduces or alleviates symptoms.

Hypothyroidism is best treated by using levothyroxine (Levoxyl, Synthroid). This synthetic version of the T4 hormone copies the action of the thyroid hormone your body would normally produce.

The medication is designed to return adequate levels of thyroid hormone to your blood. Once hormone levels are restored, symptoms of the condition are likely to disappear or at least become much more manageable.

Once you start treatment, it will take several weeks before you’ll begin feeling relief. You’ll require follow-up blood tests to monitor your progress. You and your doctor will work together to find a dose and a treatment plan that best addresses your symptoms. This can take some time.

In most cases, people with hypothyroidism must remain on this medication their entire lives. However, the amount you take may need to be adjusted, especially if you have Hashimoto’s thyroiditis. To make sure your medication is still working properly, your doctor will likely test your TSH levels yearly.

If blood levels indicate the medication isn’t working as well as it should, your doctor will adjust the dose until a balance is achieved.

Alternative treatments

Besides standard thyroid medications, animal extracts that contain thyroid hormones are also available. These extracts come from the thyroid glands of pigs. They contain both T4 and triiodothyronine (T3).

If you take levothyroxine, you’re only receiving T4. However, that’s all you need because your body is capable of producing T3 from the synthetic T4.

Research has found medications with animal extracts to be similar to levothyroxine. Other studies have indicated that taking animal thyroid extract may reduce thyroid symptoms but cause more side effects. Currently, animal thyroid extracts aren’t routinely recommended.

You can also buy glandular extract supplements in some health food stores. Additionally, studies suggest that selenium supplements may help people with hypothyroidism caused by autoimmune disease, though research is mixed.

Note that dietary supplements aren’t regulated as drugs by the Food and Drug Administration (FDA). Because of this, their potency, legitimacy, and purity aren’t guaranteed.

Use these products at your own risk. It’s important to tell your doctor if you decide to try a supplement so they can adjust your treatment accordingly.

What are the complications of hypothyroidism?

Complications of hypothyroidism include:

heart problems
goiter
nerve injury
peripheral neuropathy
carpal tunnel syndrome
reduced kidney function
myxedema coma, in cases of severe disease
obstructive sleep apnea
mental health issues, like anxiety and depression
joint pain
balance issues
obesity
high cholesterol
infertility
preeclampsia and anemia during pregnancy
birth defects

Special dietary recommendations

As a general rule, you don’t need to follow a specific diet for hypothyroidism. However, there are some recommendations to keep in mind.

Eat a balanced diet

Your thyroid needs adequate amounts of iodine to fully function, but you don’t need to take an iodine supplement to achieve that.

There are plenty of iodine-rich foods, including:

iodized salt
dairy products like milk, yogurt, and cheese
eggs
seafood
seaweed

In general, a balanced diet should provide enough iodine for most people.

Monitor your soy intake

Soy may be linked to hypothyroidism. Drinking or eating too many soy products may lower thyroid function, especially in people with thyroid disorders. However, more research in this area is needed.

Soy is found in:

tofu
vegan cheese and meat products
soy milk
soybeans
soy sauce

It’s especially important for caregivers to monitor the soy intake of infants who need hypothyroidism treatment and also drink soy formula.

Be smart with fiber

Fiber may interfere with thyroid hormone absorption. Too much dietary fiber may prevent your body from getting the hormones it needs from thyroid medications.

Fiber is vital, so don’t skip it entirely. Instead, avoid taking your medication within several hours of eating high-fiber foods.

Avoid taking thyroid medication with other supplements

If you take supplements or medications in addition to thyroid medications, try to take them at different times. Other medications can interfere with absorption, so it’s best to take your thyroid medication without other supplements, medications, or foods.

Talk it out

Having a chronic health condition can be difficult, especially if it’s accompanied by other health concerns. Since hypothyroidism can cause depression and fatigue, it may also make your relationships more challenging.

Find people with whom you can openly express your feelings and experiences. This might be a:

mental health counselor
close friend
family member
a support group of other people living with the condition

Some hospitals sponsor meetings for people with health conditions including hypothyroidism. Ask for a recommendation from your doctor and consider attending a meeting.

Research indicates that online communities may also help strengthen social connections, provide a supportive space, and help people with chronic illnesses share advice.

Support groups can help you connect with people who understand exactly what you’re experiencing while offering a guiding hand.

What’s the connection between hypothyroidism and depression?

When levels of thyroid hormones are low, your body’s natural functions lag. This can cause a variety of symptoms, including fatigue, weight gain, and even depression.

A small 2016 study found that 60 percent of participants with hypothyroidism exhibited some symptoms of depression.

Hypothyroidism may cause a range of mental health difficulties. This can make diagnosing hypothyroidism difficult. Before making a treatment plan for mental health issues, doctors may consider testing for an underactive thyroid.

Depression and hypothyroidism can share several symptoms. These include:

fatigue
weight gain
depressed mood
reduced desire and satisfaction
difficulty concentrating

The two conditions also have symptoms that may distinguish them from one another. For hypothyroidism, problems such as dry skin, constipation, and hair loss are common. For depression alone, these conditions wouldn’t be expected.

Depression is often a diagnosis made based on symptoms and medical history. Low thyroid function is diagnosed with a physical exam and blood tests. To see whether there’s a link between your depression and your thyroid function, your doctor can order these tests for a definitive diagnosis.

If your depression is caused only by hypothyroidism, correcting the thyroid disorder should treat the depression. If it doesn’t, your doctor may prescribe medications for both conditions. They’ll slowly adjust your doses until your depression and hypothyroidism are better managed.

What’s the connection between hypothyroidism and anxiety?

While hypothyroidism has long been associated with depression, a 2016 study suggested it may be associated with anxiety too.

Researchers evaluated 100 people between the ages of 18 and 45 who had a known history of hypothyroidism. Using an anxiety questionnaire, they found that around 63 percent of them met the criteria for some form of anxiety.

Larger and more focused studies on anxiety may help determine whether a true connection exists between hypothyroidism and anxiety.

It’s important for you and your doctor to discuss all your symptoms when being evaluated for thyroid or mental health conditions.

What’s the effect of hypothyroidism on pregnancy?

People with thyroid problems can and very often do have healthy pregnancies. Still, hypothyroidism can pose a particular set of challenges for pregnancy.

Low thyroid function or unmanaged hypothyroidism during pregnancy can cause:

anemia
miscarriage
preeclampsia
stillbirth
low birth weight
brain development problems
birth defects

What’s the connection between hypothyroidism and weight gain?

Your thyroid is responsible for many of your body’s daily functions, including metabolism, organ function, and temperature control. When your body doesn’t produce enough thyroid hormone, all of these functions can slow down.

If your thyroid gland doesn’t function properly, your basal metabolic rate — a measurement of the amount of energy your body uses at rest — may be low. As a result, an underactive thyroid may lead to some weight gain. The more severe the condition is, the greater your weight gain is likely to be.

The typical amount of weight gain isn’t very high, though. Most people will gain somewhere between 5 and 10 pounds.

Properly treating the condition may lead you to lose any weight you gained while your thyroid levels were not treated. However, keep in mind that that’s not always the case. Symptoms of an underactive thyroid, including weight gain, often develop over a long period of time and may not be caused by a thyroid disorder alone.

If your weight stays the same, it doesn’t mean the condition isn’t being properly treated. Instead, it may indicate that your weight gain was the result of lifestyle or other conditions rather than low hormone levels.

The takeaway

Your body naturally goes through changes as you get older. If you notice a significant difference in how you feel or how your body is responding, talk with your doctor to see whether a thyroid problem may be affecting you. If you’re a woman over age 60, remember that you’re at higher risk of a thyroid disorder.

If you have hypothyroidism, you’ll probably need to take thyroid medications for the rest of your life. Still, it’s likely that medication will help relieve or resolve your symptoms. You may also benefit from joining a support group for people living with hypothyroidism.