by Keith R. Holden, M.D., Contributor | Waking Times
Research on the placebo effect is revealing some amazing discoveries about the power of belief. Placebos were created to control for suggestion, imagination, and bias in both investigators and patients in clinical studies.(1) At the time placebos were first introduced into medical research, investigators didn’t know how they produced their effects. As the field of neuroscience has evolved, it is becoming clear that belief induced within the context surrounding the placebo produces very specific and powerful physiologic effects.
Research shows there are actually multiple placebo effects. In other words, there are multiple ways the placebo influences the body-mind to heal depending upon the therapy or condition being treated. This research shows that the placebo effect is mediated by the release of neurotransmitters, consistently impacts certain areas of the brain, and even mirrors the action of pharmaceutical drugs on human physiology.(2)
Randomized double-blind placebo-controlled trials are the gold standard for proving effectiveness of a medication. The placebo – a pill containing no active substance – is used in these trials to act as a comparison for the active drug being tested. If you say the words ‘placebo effect’ to a pharmaceutical industry researcher, they might cringe. This is because it is not uncommon for the placebo to beat the active drug in clinical trials, and this is especially true for antidepressants.
Antidepressants versus placebos
In 1998, researchers published a meta-analysis of the effectiveness of sixteen antidepressant medications. They found that 25% of the effectiveness was due to the specific action of the drug, 25% was due to spontaneous remission, and 50% was due to the placebo effect.(3) Ten years later another meta-analysis of antidepressant clinical trials for four modern antidepressants was published. It showed antidepressants were clinically significant in only a few relatively small studies conducted on extremely severely depressed patients. For moderately depressed patients, these antidepressants had no effect at all.(4)