An antioxidant helps to prevent the oxidation of other molecules.  Oxidation is reaction by which one molecule takes electrons from another molecule.  This process is facilitated by the presence of oxygen.  Oxidation leaves the latter molecule unstable, as a free radical.  These free radicals spin off, wreaking havoc on other cells in chain reactions that can cause widespread cellular damage.

Antioxidants step in to cut off this process before it begins by allowing themselves to become oxidized instead of any other surrounding cells.   Antioxidants are more prone to loose their electrons than the other cells around them, which they do without causing additional, collateral damage.

Common antioxidants include: Vitamins A, E and C as well as Selenium and other herbal supplements.  The body also creates its own antioxidant enzymes.

Connection to psoriasis: Free-radicals, mentioned above, have been attributed to the development of the scaly skin that is a common side effect of psoriasis.

The relationship between oxidants / antioxidants and psoriasis is still being explored.  A connection has been drawn mainly from an imbalance of these molecules in skin affected by psoriasis, including an abundance of oxidants and a dearth of antioxidants.

The goal with antioxidants, as with most aspects of health, is balance.  If you’re healthy all around then your body will have a healthy level of antioxidants.  Taking too many antioxidant supplements with the intention of super-charging your system will most likely cause more damage than good.