Can Gluten Cause Anemia?
Iron deficiency anemia is one of the most common nutritional deficiencies found in undiagnosed or newly diagnosed celiac disease patients. This might raise some questions about the relationship between the two conditions. Can gluten cause iron deficiency anemia? And can a gluten-free diet cure anemia? These questions and more will be answered in this article.
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 parts of the body. Without oxygen reaching tissues in the body, 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:
- Deficiency of essential nutrients (iron, B-vitamins, etc.)
- Inability to produce the protein hemoglobin
- An issue with the structure of red blood cells
- An issue with the bone marrow’s ability to make red blood cells
Does Gluten Cause Anemia?
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. So you might be wondering, does gluten cause anemia?
Patients with celiac disease or NCGS are often unable to properly absorb iron due to damage to the small intestine (known as villous atrophy). In addition, gluten can damage the acid producing cells of the stomach. Acid is a necessary component for iron absorption, so this lack of acid can lead to anemia even if the small intestine is not damaged (e.g., without villous atrophy).
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 celiac patients to try to heal, especially if their anemia goes undiagnosed.
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 190 adult patients with iron deficiency anemia studied this. The adults were screened for celiac disease by duodenal biopsy and the 26 people (24 women, 2 men) diagnosed with celiac disease were asked to follow a gluten-free diet alone without iron supplementation. After six months of a gluten-free diet, follow up duodenal biopsies and hematological 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, still only one patient was anemic, and 55.5% reversed their iron deficiency. Note this study did not include people with NCGS, but provides promising evidence that iron deficiency anemia can often be resolved in newly-diagnosed celiac disease patients by following a gluten-free diet.
Other Ways Gluten Can Contribute to Anemia in Celiac or 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 several 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 weak and can rupture prematurely.
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, and all the symptoms that come with it. 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.