Comment: Not exactly, but somewhat true.  The placebo effect is real and can be amazing, but first off it doesn't "quite often work", but it sometimes works.  Also, when it works it often isn't long lasting.  The placebo effect can have a real change in peoples'mental well being (hence feeling better) but there is little to no real evidence that there is any reversal in disease progression.  It can be noted though that a better mental state typically means less stress, and less stress can help bodies fight infections and slow the progression of some diseases.