Sorry about that - the last few times I've tried to respond have ended in failure.
So.. statistically, on the basis of responses so far it's fair to say that 100% of respondents who suffer from Psoriasis drink and smoke or have smoked at some point in time.
3/4 of us are allergy-prone and come from an allergy background. I'm trying to establish if, for example, smoking/alcohol causes toxins to build up for those of us with an allergy history that causes a reaction - psoriasis. To be a smoker or to have smoked or to live with a smoker could (for example) be the key. Whilst quitting would take away the immediate cause, it could be hanging around in the body.
If the liver houses the huild-up then a liver-cleanse would logically assist the cause of Psoriasis but continuing the cause could still be adding to it.