What is the main cause of atopic dermatitis?

Atopic dermatitis, also known as eczema, primarily arises from a combination of an overactive immune response and genetic predisposition. Individuals with atopic dermatitis tend to have an abnormal function of their skin's barrier, which is genetic in nature and leads to increased susceptibility to environmental allergens and irritants. This overactive immune response results in an inflammatory reaction of the skin, characterized by redness, itching, and dryness.

Research indicates that various factors, including certain gene mutations that affect the production of filaggrin—a protein essential for maintaining the skin barrier—play a crucial role in the development of the condition. The interplay between genetic factors and the immune system is central to understanding how atopic dermatitis manifests and persists, making this the main cause of the condition.

While food allergies, environmental pollutants, and overexposure to UV light can contribute to the exacerbation of symptoms or trigger episodes in some individuals, they are not the primary causes of atopic dermatitis itself. The root cause lies in the intrinsic immune and genetic factors that characterize the disease.