The Rumor: Your mind-set has no influence on a medicine's effectiveness

You’ve heard of the placebo effect, right? That's what occurs when patients think they’re getting a fancy new drug, but what they’re really getting is just a sugar pill. Then, in a case of "mind over medicine," they start to recover from their ailment as though they'd been taking the real deal. 

But the placebo effect has a dark side, too -- a sort of negative placebo effect called the nocebo effect. It’s what happens when you’re given a sugar pill, are told it's a drug that has terrible side effects, then start to exhibit those symptoms. The nocebo effect can also occur when a doctor tells you a surgery or procedure could have negative results: Just knowing the risks could negatively impact your recovery… all because of the power of suggestion.

Seems a little far-fetched, doesn't it? Is there any proof behind the idea that the power of positive (or negative) thinking can actually affect your health?

The Verdict: If you believe a treatment won't help you, it probably won't -- and vice versa

“People have been noticing this for quite some time,” says John Kelley, Ph.D., deputy director of Harvard Medical School's Program in Placebo Studies & Therapeutic Encounter. “Whenever you look at any randomized control trials, it’s surprising how similarly the side-effect profile for the placebo often mirrors the side-effect profile for the active [treatment]... It’s the power of the imagination. If you ask someone to imagine a visual scene in their minds, you can see on an MRI that their occipital lobes -- the parts of their brains involved with vision -- are activated. If you tell people to imagine doing some physical activity, you’ll see the motor cortex showing activation. Just imagining something is happening is enough to activate those portions of the brain associated with that thought, or worry, or pain.”

In 2012, researchers from the Technical University of Munich in Germany published an in-depth review on the nocebo effect. They looked at 31 empirical studies and found that not only does the nocebo effect exist, it’s surprisingly common. It’s also causing an ethical dilemma for doctors and nurses: If they inform patients as to the potential risks and negative side effects of a given treatment (radiation, chemotherapy, surgery, medication), the patients may believe they'll experience those harmful results -- and it could be a self-fulfilling prophecy. But if they don't tell patients the risks, they can be sued for malpractice for violating informed-consent laws. Doctors can't leave anything out, even if they fear that providing all of the scary details may hinder their patients’ recovery.  

The big question in the medical community now is how to circumvent this ethical catch-22, and there are a few interesting possibilities. “We’re working on open-label placebo [treatments],” says Kelley. “The patient knows we’re giving them a placebo, but we explain the positive results placebos can have, [so] the patient has a positive expectation and there are more positive results… Believing in a placebo isn't going to reduce brain tumors or heal broken bones. But it can work with more subjective outcomes, like the degree to which you feel pain, or nausea, or perhaps even depression.”

The moral here? Think positively about the medicine and treatments you receive, and believe that the benefits will far outweigh the risks. If you can do that, you'll increase your chances of having a good outcome.


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