Seborrheic dermatitis is a common disease of the skin that involves the so-called seborrheic areas (scalp, the groove to the sides of the nose and central area of the torso). In those areas scaly, flaky, shiny and oily patches may appear.

There are two main types:

  • Seborrheic dermatitis of the adult, well known,  generally of chronic nature.
  • Seborrheic dermatitis of unweaned babies, tipically found in the buttock-perineal area and the scalp, with different manifestations.

Seborrheic dermatitis of the infant is a transitional disorder toward different diseases such as atopic dermatitis or psoriasis.
The Seborrheic dermatitis of the adult, considered all types of it, is a very common disease. The most serious forms, namely those that require dermatological advice, only  affect 5% of the population, mostly males and during the winter. Statistics also indicate how the seborrheic dermatitis is a disorder in continuous increase probably because of the pollution.
Seborrheic Dermatitis usually shows itself as an accumulation of sebum in the horny layer , with consequent flaking and oedema  at the level of the dermis. A  bacterial infection  or Candida  can also be present. The discomfort may vary but is usually not serious and is often described as itching, inflammation and redness; on the other hand the psychological distress is more relevant.

The causes of seborrheic dermatitis are uncertain.
The main factors to consider are:

  • Excessive activity of the sebaceous glands (oily skin)
  • Genetic Predisposition
  • Nutritional deficiencies
  • Stress and hectic life, mood swings
  • Poor hygiene
  • Microbial agents activitie (especially Malassezia furfur)
  • Cleansing with products that are irritating
  • Immune deficiency (85% of subjects with HIV are affected)
  • Correlation with psoriasis

Quite often forms of Seborrheic Dermatitis are found in patients affected by serious pathologies of the neurovegetative system, in particular those people suffering from Parkinson or epilepsy.
There are no resolutive therapies. The objectives of the cosmetic treatment are the reduction of the inflammatory reaction, the production of sebum and colonization of Malassezia.
It is essential to balance the function of draining and cleaning of the skin just to regulate the activity of the sebaceous glands; in addition to this it is very important to try and  cleanse the skin and scalp with delicate active ingredients, with antimycotics and with agents that promote desquamation.