I am not sure just what you are trying to ask. Most people think the word 'placebo' is a synonym for "phony", and you need to explain why you say "wanting to live longer" instead of "living longer", as if it were a scam of some sort.
The bible presents five sources of healing: 1. Nature - it is the nature of a living creature to heal itself 2. A merry heart 3. Sleep 4. Medicine 5. The manifestation of the holy spirit
A surprise for religious people: prayer is not in the list.