I have had Psoriasis for years now and it has always been there. I have done a lot of reading about it. One thing is for certain, don't listen to what the medical doctors tell you, as they apparently are more focused on prescribing you topical steroid creams to put on the reddish pink Psoriasis patches you get on your body and less concerned about treating the problem from inside your body.
Definitely stay away from anything with pork in it!!! I don't know why but pork is not good for anyone who has Psoriasis as it can make you flare up with more psoriasis. Stay away from processed meats, lunch meat. Stay away from sugars and starches too.
Here is a book that I am reading that I definitely would recommend reading:
Healing Psoriasis: The Natural Alternative by John O. Pagano
Take care and drop me an e-mail if you have any questions.