In the quest to identify and reduce potential triggers or causes of atopic dermatitis, many researchers have started to look at the link between atopic dermatitis and a common food allergen, gluten. While the gluten-free diet and the production of gluten-free foods on a large scale may have only arisen in the past few years, the damaging effects of gluten intolerance, also known as celiac disease, have been around and causing frustration for those with it for much longer.
What is celiac disease?
Celiac disease is a very complicated condition that stems from the body’s inappropriate immune response to gluten. The term gluten refers to a family of proteins that can be found in rye, barley, and wheat, among other potential sources. When an individual is sensitive or intolerant to gluten, their body mistakenly attacks itself, specifically its intestines, when gluten is being digested. This can impact the tissues and structures that line the intestines and help us absorb the nutrients we need. Gluten intolerance, and thus, celiac disease, can vary greatly from person to person. It has been estimated that there are more than 200 potential symptoms related to gluten intolerance, including indigestion, constipation, diarrhea, and other digestive issues. In addition to these, it has also been hypothesized that gluten intolerance can contribute to feelings of anxiety or depression, joint or bone pain, arthritis, and fatigue.1
Celiac disease is typically diagnosed using a blood test looking for specific antibodies, including antibodies against gliadin, which is a part of gluten. If these antibodies are present, it signifies that the body may be launching an attack in response to gliadin (or gluten) being digested. An additional symptom of gluten intolerance or celiac disease is a skin rash called dermatitis herpetiformis, which can get confused with atopic dermatitis.1,2
Celiac disease and atopic dermatitis
A budding area of research includes studies on the relationship of gluten intolerance and autoimmune or allergic conditions. Some researchers have hypothesized that the autoimmune-like reaction to gluten in the body may trigger or exacerbate other similar conditions. For example, it has been hypothesized that the damage to the mucosal lining of the intestines (a barrier that protects us from invading or infectious particles) may leave the body more susceptible to pathogens or allergens that could trigger other reactions far away from the intestines, such as skin conditions like atopic dermatitis.3
Much of this research is still ongoing, and many studies are small or limited in scope. However, one study found that within a large population of adults with celiac disease (over 1,000 individuals), the prevalence of atopic dermatitis was 3 times higher than the prevalence in the general population. Additionally, relatives of these individuals with celiac disease were two times more likely to have atopic dermatitis as well. This suggests that there could be a link between celiac disease and atopic dermatitis, and this link may have a genetic component, just like atopic dermatitis may have. However, much more information needs to be gathered to strengthen this link.2,3
Dermatitis herpetiformis versus atopic dermatitis
Dermatitis herpetiformis (DH) and atopic dermatitis can often be confused, even by medical professionals. It has been estimated that four out of five individuals with DH have celiac disease, and that this skin condition may respond quickly to removing gluten from the diet. DH may present in situations other than for those with gluten intolerance, however, celiac disease and DH are strongly associated with one another, making DH a classic sign of the condition. DH presents with symmetrical bumps on the skin that are fluid-filled and look like blisters. DH is called herpetiformis due to its appearance being similar to that of herpes, however, DH is not herpes. Individuals with DH may experience severe itching and burning.4
Atopic dermatitis, in most cases, will not respond as immediately to gluten-free diets, if it even responds at all. Atopic dermatitis may occasionally have lesions that have clear fluid within them, however, it is typically characterized by dry, itchy, scaly patches. The skin is generally more cracked and thickened in atopic dermatitis than in DH. A skin biopsy may be appropriate to determine which skin condition is affecting an individual since both can look similar at times.