In this article
Hashimoto’s is a thyroid autoimmune disorder that occurs when your immune system attacks and destroys your thyroid cells. Because of this, your thyroid gland becomes underproductive, resulting in low thyroid hormone levels, a condition called hypothyroidism. In fact, Hashimoto’s is the primary cause of hypothyroidism.
Hashimoto’s is commonly associated with symptoms like weight gain, fatigue, or cold intolerance. But Hashimoto’s can also cause symptoms you may be unfamiliar with, such as changes in your blood cell counts.
About 50% of those with a thyroid disorder have an abnormal blood cell count, also known as a complete blood count or CBC. This article explores the link between thyroid hormone levels and your blood cell count.
A blood count is a standard blood test that provides your healthcare provider with information about the cells in your blood.
Your blood contains three main types of cells, each with a unique function:
- Red blood cells (RBC) carry oxygen from the lungs to the rest of your body.
- White blood cells (WBC) fight off infections and other diseases.
- Platelets help stop bleeding by forming a blood clot.
Any of these counts can be further analyzed by conducting additional lab tests. For instance, if your red blood cell count is low, your healthcare provider may also look at the following to better understand why these levels are outside the normal range: i
- Hemoglobin is a specific protein in your RBCs.
- Hematocrit is the volume of blood that makes up your RBCs.
- Mean corpuscular volume is the average size of your RBCs.
Thyroid disorders - both hypothyroidism and hyperthyroidism (high thyroid hormone levels) - can impact any of your blood cells. Why is this?
For those with hypothyroidism, a lack of thyroid hormone causes three things to happen:
- Your bone marrow can’t make enough hemoglobin and other red blood cell precursors to meet your body’s demands, affecting the formation of red blood cells.
- Erythropoietin levels decrease, slowing the formation of new red blood cells.
- Your tissues may not get enough oxygen resulting in symptoms of anemia.
Substantial evidence supports the link between low red blood cell and hemoglobin levels in those with Hashimoto’s or hypothyroidism. A 2020 study showed that 50% of hypothyroidism patients had low hemoglobin. But, the link between Hashimoto’s and abnormal platelets or white blood cell counts is less clear.
That same 2020 study showed abnormalities in red blood cells, hemoglobin, and white blood cells were common in those with a thyroid disorder. About 5% of hypothyroidism patients in this study had white blood cell levels above the reference range. Platelet counts were not affected in this study, which differs from other studies.
Those with hypothyroidism commonly have decreased red blood cells or hemoglobin, a medical condition called anemia. And since red blood cells play a crucial role in carrying oxygen throughout your body, a lack of these cells can result in symptoms of anemia, including:
- Appearing pale
- Shortness of breath
Symptoms of anemia may develop slowly, depending on your degree of anemia. As you might be able to tell, some of the symptoms overlap with those commonly seen in individuals with autoimmune thyroid disease like Hashimoto’s.
Over 40% of individuals with overt hypothyroidism were found to have anemia, according to a 2017 study. People with Hashimoto’s develop anemia for several reasons. First is low thyroid hormone levels. A deficiency in thyroid hormones reduces hemoglobin formation in your bone marrow, ultimately decreasing red blood cells. The second is iron deficiency.
While iron deficiency is the most common cause of anemia, a deficiency in folate and vitamin B12 can also cause anemia in those with autoimmune diseases like Hashimoto’s. Roughly 25% of anemia cases in those with a thyroid disorder are due to these two deficiencies.
Iron deficiency anemia
Iron is essential for producing thyroid hormones - T3 (triiodothyronine) and T4 (thyroxine). Your thyroid mainly produces T4, the inactive form. To affect your cells, thyroid hormone must convert T4 to T3, the active state. And iron is essential for making this conversion happen. A lack of iron would limit how much T4 can convert to T3.
Iron deficiency anemia is common in those with Hashimoto’s, especially at the time of diagnosis or when untreated. Over 40% of women with untreated hypothyroidism reported having iron deficiency anemia.
Symptoms of iron deficiency anemia are the same as other types of anemia. So, checking your blood level is the only way to tell if you are iron deficient.
Treatment for an abnormal blood count depends on the abnormal value and the underlying cause.
For instance, iron deficiency anemia is managed in several ways. If you have mild to moderate iron deficiency, your healthcare provider may recommend taking over-the-counter iron supplements or eating iron-rich foods. On the other hand, a severe iron deficiency may require intravenous (IV) iron infusions or even a blood transfusion.
If your abnormal blood counts are due to Hashimoto’s or other thyroid disorders, achieving a euthyroid state will help improve your blood counts. A euthyroid state, or when your body has an appropriate amount of thyroid hormone, is typically achieved by taking a thyroid hormone replacement medication.
Healthcare providers are encouraged to check blood counts on a routine basis in patients with hypothyroidism, Hashimoto’s, and other thyroid disorders. If your blood counts have not been tested recently, ask your healthcare provider about it. Addressing underlying deficiencies, including mild ones, can make a difference in your thyroid function and relief of symptoms.
Whether it is addressing underlying nutrient deficiencies, changing your thyroid medication dose, or checking your thyroid function, Paloma Health has you covered. Here at Paloma, our team of expert thyroid providers and nutritionists deliver personalized treatment for hypothyroidism. The best part: this can all be done from the comfort of your home. Join our growing community today.