Can Gluten Cause Anemia?

What is Anemia?

Anemia is a condition in which the body has a lower than normal number of red blood cells or quantity of hemoglobin. Because red blood cells carry oxygen, this leads to the lack of ability to deliver oxygen to the cells of the body. Without adequate oxygen, energy cannot be generated and the body will fail to function, repair, heal and generally maintain itself.

What are the symptoms of Anemia?

Anemia can cause a variety of symptoms, all generally related to the fact that not enough oxygen is reaching the tissues in the body.

• Fatigue/exhaustion – feeling tired even after a full nights sleep
• Shortness of breath – feeling out of breath even from minor exertion
• Brain fog – feeling unable to focus and a lack of mental clarity
• Muscle pain – feeling discomfort or knots of tightness in your muscles, or experiencing muscle spasms
• Dizziness – feeling faint, woozy, weak, or unsteady
• Exercise intolerance – feeling unable to perform physical exercise that a person of the same age and fitness level normally could. Exercise intolerance may also involve unusually severe post-exercise pain, fatigue, nausea, vomiting, or other negative effects.

It’s important to note that these symptoms are similar to those of an underactive thyroid (hypothyroidism). Patients are often misdiagnosed or led down the wrong path of testing and treatment if both conditions are not explored. If you’re experiencing these symptoms, advocate for yourself by asking questions about testing for both conditions.

What Causes Anemia?

Anemia can be caused by a number of different factors:

1. Deficiency of essential nutrients (iron, B-vitamins, etc.)
2. Inability to produce the protein hemoglobin
3. An issue with the structure of red blood cells
4. An issue with the bone marrow’s ability to make red blood cells

How Gluten Related Disorders Can Cause Anemia

1. Intestinal Injury & Malabsorption (Celiac Disease)

Celiac disease damages the proximal small intestine (duodenum) – the main site for iron, B12, and folate uptake.  These nutrient deficiencies are the primary culprits that drive iron deficiency anemia (IDA), and macrocytosis (large cell anemia).

2. Non Celiac Gluten/Wheat Sensitivity (NCGS)

Anemia is also reported in patients with NCGS.  A 2023 study reported ~35% iron deficiency anemia prevalence in NCGS.  For these patients, a gluten free diet can reverse the anemia and other gluten related symptoms.

3. Low Stomach Acid & Medication Effects

Gastric acid helps convert ferric to absorbable ferrous iron and keeps non-heme (plant based) iron soluble. Gluten has been shown to damage the acid producing cells of the stomach.  The side effect – low acid production (achlorhydria).  Without adequate acid, nutrients like iron, B-12, copper, and zinc are not adequately absorbed.  These nutrient deficiencies contribute to the development of several different types of anemia. In addition, gluten can cause acid reflux disease.  The most common medical interventions – proton pump inhibitors and H2 blockers further contribute to achlorhydria.  Patients who are misdiagnosed are often caught in this vicious cycle, that leads to chronic malabsorption of key nutrients needed by the body to form and regulate red blood cells.

4.  Autoimmune Hemolytic Anemia (AIHA)

Aside from celiac disease, gluten has been shown to trigger other forms of autoimmunity.  AIHA is a condition where the red blood cells are damaged by the immune system, triggering hemolytic anemia.  Researchers have linked gluten as a rare cause of AIHA.

5. Chronic Inflammation & Hepcidin

Gluten induced systemic and GI tract mucosal inflammation can elevate hepcidin.  High levels of hepcidin, trap iron in storage and reduce intestinal iron absorption.  This combination reduces the process erythropoiesis (red blood cell production.  This is commonly referred to as anemia of chronic inflammation, and occurs even when iron intake is adequate.

6. Glyphosate Use On Grains

Though not directly related to gluten, the application of glyphosate on our grain crops is a common agricultural practice.  It is well established that glyphosate acts as a mineral chelator, binding essential minerals like iron and zinc.  This binding effect could potentially lead to mineral deficiencies in people consuming these grains.

Iron Deficiency Anemia & Gluten

Iron deficiency anemia is one the most common nutritional deficits found in patients with celiac disease and non-celiac gluten sensitivity (NCGS), and it has been reported as the most frequent extraintestinal symptom in adult celiac disease. It may also be the primary symptom experienced by celiacs, even in the absence of diarrhea or weight loss.  While eating gluten may not immediately cause the onset of anemia, eating gluten can cause iron loss over time. This initially leads to a slow or gradual onset of symptoms, but as more time passes, a major iron deficiency anemia can develop. As anemia leads to oxygen deficiency, it can reduce the body’s ability to generate energy and inhibit the healing process. This creates a difficult cycle for gluten sensitive patients to try to heal, especially if their anemia goes undiagnosed.

Other Nutritional Anemias Caused by Celiac & NCGS

While Iron is thought to be the primary culprit of anemia, the truth is that there are a number of other gluten-induced nutritional deficiencies that can contribute to other forms of anemia. Patients with undiagnosed celiac disease and NCGS are often deficient in vitamins B6, B12, folate, copper, vitamin C, and vitamin E.

Vitamin B6 

Vitamin B6 is absorbed in the proximal small bowel, which is the most prominent site affected in celiac patients. However, vitamin B6 levels have been shown to return to normal levels after following a gluten-free diet. Vitamin B6 deficiency can lead to microcytic hypochromic and macrocytic anemia.

Vitamin B12

While the main site of vitamin B12 absorption is the distal ileum, some is also absorbed passively along the entire small bowel. Deficiency of vitamin B12 is common in celiac disease and frequently results in anemia. Vitamin B12 deficiency can lead to macrocytic anemia.

Folate

Folate is primarily absorbed in the jejunum, and malabsorption is frequent in diseases that affect the small intestines, like celiac disease. Folate deficiency can lead to macrocytic anemia.

Copper

Research shows that copper uptake is significantly reduced in patients with proximal intestinal disease, like celiac disease, compared with normal subjects. In fact one study showed that copper levels were restored to normal levels after following a gluten-free diet. In addition, another study even found copper deficiencies in infants with celiac disease. Copper deficiency can lead to microcytic hypochromic anemia.

Vitamin C

Vitamin C is absorbed in the jejunum, a primary site of small intestine inflammation found in celiac disease, so vitamin C deficiency is common in untreated celiac patients. It’s one worth supplementing, as vitamin C can also reduce inflammatory damage caused by gluten. Vitamin C deficiency can lead to hemolytic anemia.

Vitamin E

Vitamin E is not well-absorbed in those with undiagnosed or unmanaged celiac disease (e.g., not consistently eating a gluten-free diet). One study concluded that “patients with celiac disease are at risk of vitamin E deficiency irrespective of their diet. Vitamin supplementation should be considered in their case, especially immediately after diagnosis of the disease and in case of breaking a gluten-free diet regime.” Vitamin E deficiency can lead to hemolytic anemia.

Deficiencies of these nutrients can lead to the following other forms of anemia:

• Microcytic hypochromic anemia: this can occur if a person is deficient in iron, copper, protein, zinc, and sometimes vitamin B6. In this type of anemia, red blood cells don’t have the necessary vitamins and minerals to properly form the oxygen carrying protein hemoglobin. Without hemoglobin, the cells are small in appearance. They are also lighter in color as oxygen provides color to RBCs.
• Macrocytic anemia: this can occur if the body is deficient in B vitamins, like B12, B6, and Folate. In this case, red blood cells don’t mature properly. They are too large and don’t carry oxygen efficiently.
• Hemolytic anemia: this can occur if an individual is deficient in vitamins C, A and E, plus antioxidants, and possibly omega-3 fatty acids. In those with hemolytic anemia, the cell wall of red blood cells is less stable and can rupture prematurely.

Can A Gluten Free Diet Help Cure Anemia?

The next logical question is then, if iron deficiency is commonly caused by celiac disease or NCGS, can eating a gluten-free diet help resolve anemia in celiac or NCGS patients? One study of 26 people (24 women, 2 men) diagnosed with celiac disease were asked to follow a gluten-free diet alone without iron supplementation. Blood tests were performed at 6, 12, and 24 months. At six months, 78% female patients recovered from anemia and 28% reversed their iron deficiency. At 12 months, all but one patient (94.4%) recovered from anemia and 50% of patients reversed their iron deficiency. After 24 months of diet, one patient was anemic, and 55.5% reversed their iron deficiency.  A 2025 multicenter study found persistent anemia in 17.8% of adults and 4.4% of children with celiac disease despite long term gluten free diet adherence. The take away? These studies provide promising evidence that iron deficiency anemia can often be resolved in celiac disease patients by following a gluten free diet – even without iron supplementation.

How Do You Know if Gluten is Causing Your Anemia?

Testing for celiac disease is a good first step.  This includes a specialized series of blood tests and an intestinal biopsy.  For NCGS, testing for HLA-DQ genetic markers can help you determine whether or not you have predisposition to react to gluten.  For more in depth details, view our testing guide here.

What Tests Help Identify Anemia?

There are several blood markers your doctor can measure to help you identify anemia.  Below is a list of tests you can ask for:

• Complete Blood Count (CBC) with differential – this test helps to identify the quantity, color, and size of your red blood cells
• Iron panel with ferritin – helps to identify circulating and stored iron.
• Intracellular Nutritional Analysis (INA) – This is an outcomes based test of your lymphocytes that helps to identify vitamin and mineral deficiencies in your cells.  More accurate than traditional serum tests which are notoriously misleading.
• Hepcidin and hs-CRP – these tests help to rule out whether your anemia is being caused by chronic inflammation.

How Long Does it Take to Correct Anemia?

The answer varies greatly on many variables to include gluten free diet compliance, diet choices, gender, physical activity, underlying health conditions, and willingness to supplement. As a general rule:

• Hemoglobin recovery takes 4-8 weeks
• Iron stores take 3-6 months or more to recover
• Macrocytosis ( elevated MCV values on lab test) can take 3-6 months to normalize.
• In my clinical experience, correction of various nutritional deficiencies typically takes 6 months.

Clinical Perspective From Dr. Osborne

Key point – Iron deficiency anemia may be the first and only indication of an underlying gluten issue. Therefore, if you have been diagnosed with iron deficiency anemia and have struggled to improve your symptoms or lab results despite increasing your iron (referred to as refractory anemia), it is highly recommended that you be tested for gluten sensitivity. While anemia is typically easy to treat in most cases, those with a gluten sensitivity or celiac disease may have a hard time resolving their deficiency. This is because gluten damages parts of the stomach and intestine where nutrients like iron, zinc, copper, B vitamins, etc. are absorbed. These deficiencies can and often do progress into anemia. Proper nutritional evaluation is a must.  As discussed above, a gluten free diet does not always lead to resolution.  In my experience, supplementation is commonly a necessity for many patients.  Especially those who continue to struggle. Are you a visual learner?  An in depth video on Anemia can be viewed below:

Frequently Asked Questions (FAQ)

Does gluten itself “cause” anemia?

Yes. In  both celiac disease and NCGS, gluten triggered intestinal injury and inflammation reduce iron/B-vitamin absorption leading to anemia.

How long until anemia improves after starting a gluten-free diet?

Hemoglobin often improves within 2-3 months; repleting iron stores typically takes 3-6+ months.  Correcting B vitamins and other minerals like copper and zinc take approximately 6 months.

Can NCGS/NCWS cause iron deficiency anemia?

Yes.  Studies show ~35% prevalence. Evaluation and treatment are often necessary. What else should be checked if iron deficiency anemia persists? Hidden gluten exposure, ongoing inflammation, H. pylori infection, autoimmune gastritis, and acid-suppressing medications are common culprits. Explore these options with your doctor.