Is There a Link Between Iron Overload and Hypothyroidism?

A Overview of Hereditary Hemochromatosis

hemochromatosis is more common in thyroid patients
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Hereditary hemochromatosis is a genetic or inherited disorder, also known as iron overload disease. It results from excessive iron absorption in your gut (from food) causing iron to become stored in organs, like your liver, heart, and pancreas.

You may be surprised to learn that thyroid dysfunction may also result from hereditary hemochromatosis. This is because iron can be deposited in your pituitary gland, causing central hypothyroidism, or less commonly, your thyroid gland, causing primary hypothyroidism.

Let's take a closer look at hemochromatosis, including how this common genetic condition manifests and is treated. 

Risk Factors 

There are a number of risk factors for developing hemochromatosis. Since hemochromatosis is an autosomal recessive condition, you would need two copies of the genetic mutation to develop it.

Moreover, being a Caucasian of Northern European descent is a risk factor. In addition, being male increases your chances of developing hemochromatosis, as women lose iron through menstruation, so they build up less iron overload. A woman's risk goes up, however, after menopause, when she is no longer menstruating.

Symptoms and Signs

The manifestations of hemochromatosis do not typically develop until an older age, and depending on which organs are affected, a person can have variable symptoms. Many people, in fact, are diagnosed with hemochromatosis (based on a family history or incidental blood tests) before they develop symptoms.

It's also important to note that iron deposition may occur within an organ without any clinical manifestations. For example, autopsy studies have revealed iron deposits in the thyroid gland of nearly all people with hemochromatosis; yet, most people with hemochromatosis do not develop primary hypothyroidism (an important point to keep in mind).

Overall, though, the more common symptoms and signs of hemochromatosis include:

  • Ongoing fatigue
  • Arthritis-like pain in joints, in particular, the middle two fingers
  • Changes in skin color, yellowish, bronze, grey, olive
  • Weakness
  • Abdominal pain (on the right from an enlarged liver)
  • Elevated blood sugars
  • Abnormal thyroid function tests
  • Abnormal liver function tests
  • High levels of iron in the blood

As the condition develops, if left untreated, a person may develop:

  • Diabetes
  • Liver damage
  • Heart damage
  • Thyroid dysfunction
  • Impotence
  • Absence or irregular menstrual periods

Diagnosis and Testing

If you are experiencing symptoms of iron overload and your doctor detects high iron levels in your blood, he can then order a blood test for the hemochromatosis gene. 

Furthermore, according to the National Institute of Diabetes and Digestive and Kidney Diseases, the following testing guidelines should be followed:

  • Siblings of people with hemochromatosis should have their blood test for the C282Y mutation (the hemochromatosis gene).
  • Parents, children, and close relatives of people with hemochromatosis should consider testing. 
  • Doctors should test people with severe and persistent fatigue, unexplained liver disease, joint pain, heart problems, erectile dysfunction, or diabetes.

    Lastly, to specifically confirm thyroid-gland involvement in hemochromatosis, an MRI of the thyroid gland can detect iron deposits. 

    Treatment

    Hemochromatosis is treated through "bloodletting" or phlebotomy—basically, the simple process of giving blood. Your doctor will develop a regular schedule for phlebotomy, as a treatment for hemochromatosis.

    A Word From Verywell

    Hemochromatosis is the most common genetic disease in the United States, and the good news is that its serious manifestations, like liver, heart, and thyroid disease, can often be prevented with proper care.

    If you have a family history of iron overload or unexplained symptoms, it's sensible to talk with your doctor about undergoing testing.

    Sources:

    Schrier SL, Bacon BR. (2018). Clinical manifestations and diagnosis of hereditary hemochromatosis. In: UpToDate, Mentzer WC (Ed), UpToDate, Waltham, MA.

    Tamagno G, De Carlo E, Murialdo G, Scandellari C. A possible link between genetic hemochromatosis and autoimmune thyroiditis. Minerva Med. 2007 Dec;98(6):769-72.