Iron deficiency increases the risk of celiac disease

There celiac disease it is a chronic autoimmune disease that affects approximately 1% of the population and develops in genetically predisposed subjects: in Italy there are official patients 245 thousandbut with the “underground” (undiagnosed celiacs) they could reach 600 thousand cases. There are around 9 thousand new diagnoses every year.

Low iron levels

One American study, published on BMJ Open Gastroenterologydemonstrated (and confirmed) that it exists a link between deficiency of iron and celiac disease. The authors, from the University of Washington in Seattle and Harvard Medical School in Boston, took into consideration the data of 336 thousand people, 1,855 of whom had celiac disease, discovering that Genetically lower iron levels are associated with a greater risk of developing the disease.

Genetic and environmental factors

The incidence of celiac disease has increased in recent decades, also thanks to improved diagnoses. The triggering factors are both genetic (DQ2 and DQ8 haplotypes) and environmental. Among the latter there would be, according to some studies, the duration of breastfeeding, exposure to gluten, perinatal factors, infections (for example that caused by rotavirus), socioeconomic factors, geographical position, composition of the microbiome, drugs. However, none of these factors have provided irrefutable evidence, nor a contribution to the prevention of celiac disease.

Anemia and celiac disease

In reverse low iron levels can be counteracted: this is the most common nutritional deficiency globally, affecting both rich and low-middle income countries. According to the authors of the new study, in the United States iron deficiency (also due to a lower presence of the mineral in the diet) has increased in step with the growth in diagnoses of celiac disease. Furthermore, anemia is more widespread in the groups most affected by the disease, such as children and adolescent and premenopausal women.

Complex relationship

Iron deficiency is present in the majority of cases of celiac disease (up to 80%) and evidence is growing of the existence of a complex relationship between the two conditions. Iron deficiency in celiac disease has often been attributed to poor iron absorption due to atrophy of the mucosa of the duodenum, which is the primary site of iron absorption. However, only 10% of dietary iron is absorbed by the duodenum to meet the body’s needs. Therefore, unless the diet is extremely poor, it is likely that a reduced mucosal surface area is not the only explanation for the deficiency.

The transferrin receptor

It plays a role too a protein, transferrin receptor 1, which increases in case of iron deficiency. One study found that receptor levels are significantly higher in subjects with celiac disease and iron deficiency than in those with iron deficiency but without celiac disease.

Immune system

Iron is also believed to contribute to the development of celiac disease through its impact on the innate immune system, on the risk of infections and on the microbiome. Hepcidin and lactoferrin, two proteins involved in iron metabolism, play a role in innate immunity and iron deficiency has been shown to impact the microbiome, which in turn impacts the development of celiac disease. It has recently been demonstrated that Iron plays a critical role in regulating the immune system in the gut: For this reason, iron deficiency can play a role in inflammatory bowel diseases and other immunological disorders.