If you live with both hypothyroidism and depression, your thyroid condition may be contributing to your symptoms of depression.

A female doctor doing a thyroid exam on a female patient with a nurse taking notesShare on Pinterest
mixetto/Getty Images

When you’re dealing with hormone imbalances, your mood and energy level can feel low one day and high the next. If you also live with a mental health condition like depression, it can be difficult to determine which of your symptoms come from hypothyroidism and which come from depression.

Having a basic understanding of how your body’s endocrine system — or your network of hormones — affects your physical and mental health can give you a better understanding of why you may be feeling tired or low in spirits.

The thyroid gland is located in your neck and impacts several functions of the body, from your heart to your nervous system.

When your thyroid and pituitary glands release hormones, they help manage your essential bodily functions, including:

  • bone growth
  • managing your heart rate
  • regulating your body temperature

Symptoms of hypothyroidism and depression interact in unexpected and sometimes unpleasant ways. It’s important to remember that while the symptoms of each condition contain a lot of overlap, you may want to avoid thinking as if one condition causes another.

Hypothyroidism occurs when your thyroid gland isn’t producing enough thyroid hormones for the body to function properly. As a result, you may experience symptoms such as:

  • weight gain
  • slow speech
  • low heart rate

On the other hand, hyperthyroidism is the opposite of hypothyroidism. It results from the thyroid gland overproducing hormones. This imbalance may lead to:

  • irregular heart rhythms
  • weight loss
  • fatigue

When your thyroid gland shows irregular hormone production, it can be linked to mental health symptoms like mania and depression.

To understand how the thyroid gland affects depression, it’s worth considering the differences between overt and subclinical thyroid disease.

There are two types of hypothyroidism:

  • Overt. Thyroid-stimulating hormone (TSH) and thyroxine (T4) blood levels are low.
  • Subclinical. TSH levels are high, but T4 is within normal range.

You can consider subclinical hypothyroidism as a milder version of hypothyroidism. Those affected tend to not experience any symptoms and don’t require treatment. Only an estimated 2% to 6% end up developing overt hypothyroidism.

The term “subclinical” means that the condition may not require clinical treatment.

The only studies that investigate the link between hypothyroidism and depression consider overt hypothyroidism’s relation to depression.

For example, this 2018 review of several studies mentions a link between overt hypothyroidism and depression. However, the evidence does suggest thyroid hormones play an essential part in your brain function. That’s why hypothyroidism may lead to mood disorders like depression.

While research shows a link between overt hypothyroidism and depression, definitive evidence of depression causing thyroid issues does not exist.

Hyperthyroidism and depression

When you consider the physical, mental, and chemical aspects of depression, you can find an association between your thyroid and its effect on your mental health.

Experts believe there is still more research needed to conclude if hyperthyroidism can cause your depression symptoms.

For example, a 2021 study in China analyzed previous lab studies of people diagnosed with major depressive disorder (MDD) and compared them with others that did not report mental health issues. The study found that the majority of participants with MDD had abnormal thyroid hormone levels.

However, this correlation between abnormal thyroid activity and depression should not be thought of as a cause of depression. These results may show that healthcare professionals should give more attention to checking blood levels, vitamin deficiencies, or thyroid issues in people with MDD.

You can consider thyroid conditions as risk factors for mood disorders — not definitive causes of MDD or other mental health conditions.

Learning the difference between symptoms of depression and hypothyroidism can help you better understand your experience.

Common symptoms of depression

Depression is one of the most common mental health conditions, but it affects each person differently. Overall, the common symptoms found in this mood disorder include:

  • lack of interest in daily activities
  • significant unexpected weight loss or gain
  • insomnia
  • excessive sleeping
  • lack of energy
  • difficulty concentrating
  • feeling inadequate
  • excessive guilt
  • recurrent thoughts of death or suicide

If you’re interested in learning more about MDD or other depressive disorders, consider our in-depth guide to depression.

Common symptoms of hypothyroidism

Like depression, symptoms of hypothyroidism can vary between individuals. However, they may include:

Shared symptoms

Typical symptoms seen in those diagnosed with hypothyroidism and depression share the following:

Given how mental health is being discussed more openly in many settings, we’re also seeing new trends in clinical research to better understand mood disorders. Consider how your hormones interact with your mood or even your mood disorders.

To answer this question, doctors and healthcare professionals conduct tests on your thyroid gland.

When you see your health practitioners, they may order blood labs to test your thyroid hormone levels. If any levels come back too high or too low, your doctor may consider more tests to see if you have a thyroid condition.

A physical exam and recent health reports, including symptoms, may also provide your doctor with more information on a potential diagnosis.

However, signs of either your depression or thyroid conditions may mimic other diseases, such as:

  • anemia
  • cancer
  • iodine deficiency
  • chronic fatigue syndrome

Finally, your doctor may request a thyroid ultrasound to examine your thyroid gland and rule out any abnormalities or growths.

There are multiple avenues of treatment for these conditions.

Hypothyroidism

Medication is the treatment of choice for hypothyroidism. Since your thyroid isn’t producing enough hormones, the standard treatment is a hormone replacement drug called levothyroxine.

You may start to see your symptoms get better once you begin your medication under a doctor’s supervision.

Hyperthyroidism

With hyperthyroidism, you have more treatment options to help you manage your symptoms. Treatment options can include:

  • Medication. Antithyroid medication helps make fewer thyroid hormones to help reduce symptoms.
  • Radioiodine therapy. Iodine therapy is taken via a capsule or liquid, which targets cell-producing thyroid hormones.
  • Surgery. The surgeon opts to remove part of the thyroid gland, which is only done in rare cases when a person develops a goiter or becomes pregnant.

Depression

There are a wide variety of treatment options available for depression. Depression is considered a serious mood disorder that’s highly treatable, offering you many roads to recovery. These could include:

Medication

Therapy

Self-help and coping

It’s important to remember that treating your thyroid disorder will not necessarily improve your symptoms of depression. Consider them both as separate conditions that overlap in their symptoms.

However, addressing any thyroid conditions may reduce your risk of developing depression later in your life. It also may improve your chances of recovery from depression if done with other recommended treatments.

Either way, consider both thyroid conditions and mental health conditions like MDD as highly treatable conditions. You can look forward to gradual improvements in your symptoms once you receive proper diagnoses and treatment options.

If you’re living with depression, it is understandable that you’d want to find out more about what’s causing or worsening your symptoms.

However, sometimes depression has no apparent cause, yet it is highly treatable.

The science remains inconclusive on whether thyroid disorders cause depression, and more research is needed to be sure. However, experts see a strong link between thyroid conditions and depression, so much so that they consider conditions like hypothyroidism to be a risk factor for depression.

If you believe you are experiencing symptoms of either thyroid conditions or depression, it is best to see your doctor and find out for sure. Both thyroid disorders and depression shouldn’t go untreated, since they may cause more serious health problems later.

Either way, treatment is available no matter the diagnosis.

If you feel overwhelmed or stuck with depression symptoms, you can talk with a mental health hotline that’s available 24/7 by phone. And while you wait for appointments with health professionals, consider finding coping strategies that work for you as you explore treatment with a doctor.

By taking control of your health today, you can look at a brighter and healthier future tomorrow.