i think that just goes to show that there should be research into the ability of the mind to heal the body.
Pharmaceutical companies spend billions of dollars on testing and medical trials to prove to regulators that their drug is not a placebo. It is not unheard of for an approved drug to score only slightly above that of a placebo in trails. See this, for example
http://www.fiercebiotech.com/story/fda-tracks-rising-impact-placebo-effect-antipsychotic-trials/2012-06-22
As to the "mind healing the body", I think we have all heard or known first-hand about people who refused to quit when seriously ill or injured or by sheer force of will beat an illness that should have killed them. While I'm happy to get vaccinated, undergo arthroscopic surgery and be prescribed antibiotics etc I think that like so much else in life, attitude does matter when it comes to staying healthy or recovering from illness and injury.
I read somewhere about studies that found the most common characteristic people with undiagnosable back pain is low job satisfaction.