Hypothyroidism and Iron Deficiency: Understanding the Connection Between Hypothyroidism and Anemia

Donna Sergi • June 21, 2024

"The content below is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition."

Eternally cold hands, exhaustion despite a full night's sleep, and more. It seems your body never feels right. 


You know these are symptoms of your hypothyroidism — but did you know they're also associated with iron-deficient anemia? 


Hypothyroidism and iron deficiency are two conditions that may make your life challenging. They may also be connected.



In this article, we explore the relationship between hypothyroidism and iron deficiency and how they affect one another.

Table of Contents

can hypothyroidism cause low iron

Is There a Connection Between Hypothyroidism and Anemia?

Yes.


While they may trigger the onset of one another, it’s essential to distinguish the connections between hypothyroidism, anemia, and iron-deficient anemia. 


Often, the terms “iron deficiency,” “anemia,” and “iron-deficient anemia” are used interchangeably, but they don’t mean the same thing. To clarify:


  • Anemia is diagnosed due to low hemoglobin. 
  • Iron deficiency is due to low iron. 
  • Iron-deficient anemia is caused by low hemoglobin and low iron. 


There are ten general types of anemia, each differentiated by its cause. Only 50% of anemia is the result of iron deficiency.

 

Studies suggest 45% to 65% of hypothyroidism patients have iron-deficient anemia (ID). Another study, examining the comorbidities (simultaneous presence of another disease) of iron-deficient anemia in 100 patients, found that 86% of participants with ID also have hypothyroidism. 


Like hypothyroidism, iron-deficient anemia is a common problem among women. At HealthierU, Dr. Donna Sergi understands the oversight traditional medicine often has regarding women-affected health issues and wants to help. As a natural nutritionist specializing in diet and thyroid dysfunction, she uses nutrition to help you reclaim your life from your condition and its symptoms. 

can hypothyroidism cause low iron

How Does Hypothyroidism Affect Iron Levels?

Hypothyroidism may adversely affect iron levels because:


  • Iron homeostasis (balance) is dependent on iron-regulating proteins (IRPs) and the iron-responsive element (IRE) activity, which is regulated by T3 hormones. Since hypothyroidism causes low T3 production, low thyroid hormone levels decrease the production of ferritin (the protein that stores iron) in the liver.   
  • Thyroid hormones are crucial in producing hydrochloric acid (stomach acid) secretion. Low stomach acid makes it difficult for the body to absorb iron from food.
  • Thyroid hormones stimulate the production of red blood cells (erythropoiesis). Reduced circulating thyroid hormones T4 and T3 may result in low iron and hemoglobin levels. 

How Does Iron Deficiency Contribute to Hypothyroidism?

Iron deficiency may lead to hypothyroidism because:


  • It affects thyroid peroxidase (TPO), the synthesis of thyroid hormones. Since this process relies on iron to produce new hormones, low iron may decrease hormone production.
  • The thyroid depends on iron to convert thyroxine (T4) into the active hormone triiodothyronine (T3). If there’s not enough iron for conversion, low T3 hormones may result, which is associated with hypothyroidism and thyroid dysfunction.
  • Iron deficiency may reduce the T3 hormone’s ability to bind to thyroid receptors, reducing thyroid activity. 

Low Iron and Hypothyroidism: What Is the Importance of Iron for Someone With Hypothyroidism?

As we previously pointed out, iron is vital to thyroid function. 


The thyroid is a nutrient-dependent gland, depending on nutrients like iron, tyrosine, selenium, and zinc to produce thyroid hormones and facilitate the conversion of T4 to T3. Without these vital minerals and vitamins, the thyroid may not function properly, which could lead to the development of hypothyroidism. This means low iron and hypothyroidism may go hand in hand. 


By eating nutrient-dense foods and supplementing your nutrient deficiencies, you may be able to help your thyroid produce and regulate the necessary components for healthy thyroid function.


Nutrition, diet, and health can often be challenging to navigate, especially when you feel like you’ve tried everything and are at the end of your rope. 


HealthierU can work with you to create a dietary regimen that reduces hypothyroidism symptoms and promotes thyroid health. Dr. Donna Sergi is Brooklyn’s premier women's health and dietary specialist. With 25 years of experience, she is the expert at helping people who think they’ve tried everything find a natural way to treat their thyroid issues and reclaim their health. 

Common Causes of Iron Deficiency

Lack of iron in the body may be caused by the following:


  • Dietary insufficiencies
  • Poor iron absorption
  • Blood loss
  • Other diseases, including chronic illnesses, digestive conditions, and inherited blood disorders



Low iron may also be associated with heavy periods and pregnancy.

Symptoms of Iron Deficiency

Symptoms of iron-deficient anemia include:



  • Pale or yellow skin (in lighter skin persons)
  • Paler than normal skin (in non-white individuals)
  • Shortness of breath
  • Rapid heartbeat
  • Dizziness
  • Tinnitus
  • Headaches
  • Craving ice (pagophagia)
  • Brittle nails and hair
  • Hair loss
  • Mouth ulcers 
  • Smooth or sore tongue
iron and hypothyroidism

How To Diagnose Iron Deficiency Caused by Hypothyroidism

Iron deficiency can be diagnosed by a serum ferritin test, which involves taking a small blood sample to measure ferritin levels. 


Ferritin is a protein produced by the liver that stores iron, making it available for use as needed. Low ferritin levels mean the body lacks adequate iron. 


Normal value ranges (nanograms per milliliter) for ferritin are:



  • Men: 30 to 400 ng/mL
  • Women: 13 to 150 ng/mL

How To Treat Iron Deficiency With Hypothyroidism

Research suggests that rebalancing iron levels may resolve thyroid dysfunction in individuals with iron deficiency-related hypothyroidism. 


Since iron deficiency is often overlooked when treating patients with hypothyroidism, correcting thyroid dysfunction with nutrition and supplements may be life-changing. This may be especially true for individuals who were told they must continue life-long thyroid replacement therapy. 


HealthierU believes in pursuing more natural avenues for treating health conditions like hypothyroidism. 



Unlike other health authorities, Dr. Donna Sergi takes the time to listen and address patient concerns. Her practice is patient-centered and empathetic, meaning your experiences and issues will not be diminished or dismissed. 

Dietary Iron

Diet is an excellent way to ensure you get the iron you need, especially if you have hypothyroidism or iron-deficient anemia. Most people with iron deficiency require 150 to 200 mg of elemental iron in their diets daily (or two to five milligrams of iron per kilogram of weight).


Foods that are high in iron (and delicious) include:


  • Red meats: Lamb, liver, pork, veal, venison, and goat
  • Seafood: Shrimp, scallops, oysters, tuna, sardines, and mackerel 
  • Vegetables: Spinach, sweet potatoes, chard, beet greens, and broccoli
  • Fruit: Strawberries, watermelon, figs, dates, raisins, dried apricots, and prunes
  • Other foods: Eggs, beans, lentils, molasses, and maple syrup



Dr. Donna Sergi specializes in making nutritional changes fun and easy. By understanding your dietary preferences and palette, she can work with you to create a nutritional treatment plan that may improve your iron deficiency and hypothyroidism. 

Supplemental Iron

Ferrous sulfate is an iron supplement used to treat iron deficiency and anemia. While you may purchase supplemental iron over the counter, a doctor may prescribe a prescription iron supplement for severe cases.


Recommended daily doses of iron supplements can vary depending on your condition and current iron levels. 


Side effects of iron supplements may include:


  • Gastrointestinal issues
  • Changes in stool
  • Flatulence
  • Teeth staining
  • Metallic taste in the mouth 

 

High doses of iron may be fatal, so only take iron supplements as recommended by your doctor. 



If you are taking supplemental iron alongside levothyroxine (a thyroid replacement hormone) for hypothyroidism, you should generally wait four hours after taking one supplement before taking the other. Iron may bond with levothyroxine, preventing it from being absorbed by the stomach. 

hypothyroid and low iron

Understanding Low Ferritin and Hypothyroidism

Since ferritin stores iron, low ferritin levels are direct indicators of iron deficiency. Generally, this is because the body isn’t getting enough iron and may be using it before it can even be stored. 


Research suggests that serum ferritin levels have a significant association with varying levels of thyroid hormones like TSH, T3, and T4. Iron deficiency, specifically serum ferritin deficiency, is thought to be one of the most common causes of thyroid dysfunction.



Let’s examine how low ferritin and hypothyroidism impact one another.

Increased TSH Levels

The relationship between ferritin levels and TSH remains generally unclear in some studies. 


For example, one study examining the relationship between ferritin and thyroid hormone levels found no association. Similar results were generated by another study examining subclinical hypothyroidism in adults. 


However, another study examined 30 thyroid subject cases, matched by age and sex, with 30 other subjects with normal thyroid function. The study found all thyroid patients had higher TSH and lower ferritin levels than the healthy thyroid group. 



This suggests that more research should be done to highlight how low ferritin increases TSH.

Reduced T3 Levels

Studies have shown that reduced T3 levels may inhibit the liver’s ability to produce ferritin. 



This is because T3 is needed for the iron proteins that create ferritin in the liver. The lack of T3 may also affect the iron-responsive element pathway, which helps signal the gene expression that creates ferritin.

Take a Natural Approach To Managing Hypothyroidism and Low Iron With HealthierU

HealhierU seeks to establish a comfortable environment where people can receive understanding, empathetic, and natural treatment for hypothyroidism and low iron.


Led by Dr. Donna Sergi, HealthierU promotes an inclusive practice that takes its time investigating patients' health issues and concerns. Their nutritional and other holistic methods may help you find relief from hypothyroidism symptoms and treatment for low iron. 



Schedule a free consultation or learn more about natural treatment for hypothyroidism today.

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