The general idea that I keep coming across is that true healing of chronic illness can only come from within. There are three main, very compatible, ideas for creating the conditions for this to happen:
1. Diet: Eliminating "toxic" foodstuffs from the diet (which may be causing the auto-immune reactions which cause the chronic condition). "Toxic" foodstuffs are generally considered to be animal proteins (meat, dairy, eggs) and a bunch of other candidates, like wheat (gluten) and an excess of grains/starch in general.
2. Energy: Chinese medicine has the concept of "energy balance" and "energy blockages", which can be fixed, or brought back into balance, by nerve stimulation (acupunture, etc.) and diet. Reiki is "curing with energy". Meditation is also considered to be able to restore energy flow within the body. I think prayer is probably a form of opening yourself to "universal energy" and so could be included in this category.
3. Pyschological: Removing the pyschological issues (self-dislike, need for attention, etc.) that prevent the body from sending the chemical signals required to regenerate the needed cells, or stop the body sending the signals that are damaging itself.
All of these ideas are basically compatible and, in my conclusion, revolve around the key idea learning to love yourself (and hence avoid cumpulsive habits like eating, overworking, etc.).