All bio-medical researchers now recognise that some dermatological pathologies are caused by oxidative chemical processes: i.e. by OXIDATIVE STRESS.
These processes are manifested almost exclusively through the release of highly reactive molecules called “FREE RADICALS”, which in biological life are represented mainly by the Reactive metabolites of Oxygen (ROM's, or Rd, Fr or ROS).
The destruction of super-oxide free radicals and metabolites that are accumulated in tissues suffering from seborrhoeic dermatitis is at the basis of every action to reinstate the normal physiologic functions of the skin tissue. Free radicals are some of the main causes of oxidative mechanisms in cells.

By FREE RADICAL we mean a chemical species that has an independent existence and that contains one or more odd electrons and is therefore highly reactive against other molecules.
Hydro-silic and peroxide radicals are very dangerous because, according to a theory already proposed by Harman in 1954, they cause damage to the membranes, alteration of the proteins and inactivity of the enzymes.

The cytotoxic action of free radicals is combated by the cellular defence systems represented by enzymes that behave as ANTIOXIDANTS: SOD (super-oxide dismutasis) combating the action of the radicals converting them into (hydrogen peroxide), CATALASIS and GLUTATIONE PEROXIDASIS which convert into pure water before the other complexes use it as a substratum to generate radicals.

Free radicals are generated both during the normal metabolic reactions that take place in the cell, and through introduction by agents such as medicines, food substances, pesticides, tobacco smoke, ultra-violets radiation.