Melody, sprouts and greens are great foods and avoiding refined sugar is also a good plan. Probiotics could help as well.

A thought about manuka honey; I use it topically whenever I have a skin lesion which looks infected - it works for me.

It is something that Alan could consider for his psoriasis (the link that I posted above suggests that it can help). You might be able to buy it from a health food shop. One things to watch out for is how pure it is - this is usually based on counting the pollen grains in it - manuka pollen has a characteristic shape - a quality product will tell you about this.