Rosacea on the face is caused by a combination of factors that are not fully understood but primarily involve inflammation and an abnormal immune response. Key causes include:
- Immune system activation leading to inflammation, possibly triggered by proteins such as cathelicidin, which cause redness and swelling. An overabundance of microscopic mites called Demodex, and bacteria associated with these mites, may also trigger this immune response and inflammation.
- Environmental and lifestyle triggers such as sunlight, heat, cold, stress, spicy foods, alcohol, hot drinks, and certain skin products can provoke or worsen rosacea symptoms.
- Genetic factors may make some individuals more susceptible, especially those with fair skin who tend to flush easily, and a family history of rosacea.
- Other possible contributors include changes in blood vessels, increased skin sensitivity, and infections like Helicobacter pylori or small intestinal bacterial overgrowth (SIBO), though these links require further research.
In summary, rosacea is primarily an inflammatory skin condition triggered by complex interactions of the immune system, microorganisms on the skin, genetic predisposition, and environmental factors.
