Seborrheic Dermatitis: Most Effective Dietary Supplements

Seborrheic dermatitis is a chronic and recurrent skin condition affecting about 1 to 3% of the adult population. It presents as erythematous scaly lesions located in areas where sebaceous activity is highest, such as the face, scalp, and trunk.

Pathophysiology

Seborrheic dermatitis is linked to two main factors: an overproduction of sebum (seborrhea) and the presence of yeasts of the Malassezia genus, which proliferate in sebum-rich skin areas. However, seborrhea alone does not fully explain the onset of the disease, as the skin lipid composition is similar in both affected and healthy individuals. The involvement of the yeast is supported by the fact that lesions appear mainly in areas where it is present in high density, and by the effectiveness of antifungal treatments. However, the severity of symptoms is not always correlated with the quantity of yeasts, suggesting that the patient's immune response also plays a role in the development of the disease.

Symptoms

The symptoms of seborrheic dermatitis vary depending on the affected body areas. On the face, erythematous plaques with oily scales often appear in the nasolabial folds, eyebrows, glabella, and anterior scalp. The scalp may be affected by fine, non-adherent dandruff or, in more severe cases, by thick scales. On the trunk, annular plaques with scaly edges usually manifest in the presternal region (base of the neck and chest). Other areas, such as hairy and genital regions, may also be affected. In newborns, seborrheic dermatitis presents as yellowish crusts on the scalp (cradle cap) and face, with possible involvement of the axillary folds and the diaper area.

Risk Factors

Certain conditions increase the risk of developing seborrheic dermatitis. HIV infection is associated with more extensive and severe forms of the disease, often resistant to treatment. People with Parkinson's disease are also more prone to marked seborrhea and severe forms of dermatitis. The disease is also more common in patients suffering from mood disorders, partly due to reduced sun exposure. Individuals with chronic alcoholism and upper aerodigestive tract cancers also demonstrate a higher prevalence of seborrheic dermatitis.

Treatment

The treatment of seborrheic dermatitis primarily involves the application of topical care. Antifungals in the form of creams or gels, such as those containing ketoconazole or lithium gluconate, are used to reduce yeast proliferation and decrease inflammation. For scalp lesions, medicated shampoos containing zinc pyrithione, ketoconazole, or selenium sulfide are effective. Topical corticosteroids can also be used short-term to treat highly inflammatory forms. However, due to the chronic nature of seborrheic dermatitis, frequent relapses often occur after stopping treatment. It is therefore essential to educate patients on the importance of regular maintenance and the necessity of following a long-term treatment to manage symptoms.