I've often wondered and not been able to tell if tomatoes affected psoriasis. A number of times now I have eaten pizza or other items with condensed tomatoes, and within two hours after eating them see a red glow around my psoriasis lesions.

The same goes for stress reduction, relaxation, or just the right food. My skin can react within hours to a great situation and start healing quickly.

The one thing I've noticed, though, about healing is that sometimes it takes Psoriasis longer to heal long term than get irritated. So, the best thing can often be try to prevent the picking and scratching, as once you get new lesions it may take some time to get rid of them naturally.

Or of course there is the medicine route, but some treatments are shorter of longer term than others.