Psoriasis Natural Treatments

I have chronic psoriasis and have gone to every doctor/tried every treatment possible to get rid of it. I thought it was stress related and still do but not as much.
My psoriasis pretty much dissapeared when i got sunburnt and went to the beach also i broke up with my loser boyfriend…so i figured beach, sn, less stress = …no psoriasis.
I recently went away with friends and started drinking beer…and in the last week my skin went from CLEAR to BOOOOOOM and I think it because of yeast!!!
I figured to do some more research on this disease and found that yeast is a cause to psoriasis. So because the professionals can’t really help me, I am going to try my own NATURAL experiment…although I am finding it hard to get a ‘YEAST FREE’ shopping list together!! HELP PLEASE – I don’t so much want recipies…just seperate foods…like tuna, corn, fetta cheese …ta

I have psoriasis on my back and it is really getting on my nerves. Does anyone know of a treatment that will get rid of it. I have tried some stuff from the doctors (cocois) but is doesn’t work.
I also have it on my scalp so anything that can help there as well would be appreciated.