Would you object to being lied to by your doctor if the lie helped you recover from an illness or surgery more quickly? Would you prefer the cold truth even if it meant prolonging your illness or recovery time? Physicians have long been counseled to have an emotionally sensitive bedside manner, but now scientists are discovering that a doctor's words also affect our biology.

Everyone is familiar with the placebo effect in which a fake medicine works on the body because the mind believes it is working, but so-called nocebos can also affect patient health. When a doctor uses negative or discouraging terms — there is "bad news"; your knee is "worn out"; medication will help "a bit" — the patient doubts his or her own faculties of recovery. And those doubts subtly become reality, say researchers. 

The issue was taken up by a recent BBC radio broadcast that addressed the problems of placebo, describing the complex discoveries being made by medical researchers.

“It’s easier to do harm than good,” explains Watts. “And this is worrisome, because nocebo’s negative influence can be found lurking in almost every aspect of medical life and beyond.”

The nocebo is a serious ethical issue because we deeply value both truth and health, but which would you choose? Professor of behavioral economics at Duke University, Dan Ariely explains the dilemma in more detail during his Big Think interview:

"We’ve done research showing that when you give people a painkiller, and you tell them it’s expensive, it works better than if you tell them it’s cheap. And it turns out that placebos are real. ... And now here is the dilemma: should we start prescribing more placebos in medicine? Should we lie to people more frequently? Because if we told people this is a placebo, it wouldn’t work. So we actually have to lie to them. But when we lie to them, it also works."