Kaptchuk tested the effect of placebo versus no treatment in 80 people with irritable bowel syndrome. Twice a day, 37 people swallowed an inert pill could not be absorbed by the body. The researchers told participants that it could improve symptoms through the placebo effect.
While 35 per cent of the patients who had not received any treatment reported an improvement, 59 per cent of the placebo group felt better. "The placebo was almost twice as effective as the control," says Kaptchuk. "That would be a great result if it was seen in a normal clinical trial of a drug."
I followed the link to the journal article and found exactly what they said to the patients:
Patients were randomized to either open-label placebo pills presented as "placebo pills made of an inert substance, like sugar pills, that have been shown in clinical studies to produce significant improvement in IBS symptoms through mind-body self-healing processes" or no-treatment controls with the same quality of interaction with providers.
The phrase 'mind-body self-healing processes' is suspiciously similar to what you hear thrown around in ads for quack cures. I wonder if this was intentional. Did they copy buzzwords from quack ads, the same way that Forer copied horoscopes for a psychology demonstration?
This study helps explain why those quack cures are so popular: they actually do work for any condition marked by a subjective experience. With this study you could legally sell sugar pills for IBS relief, as long as the ad mimicked what these doctors told the patients.
Of course, the smart thing to do is skip the middleman and convince yourself that exercise or yoga or meditation or something similar will cause a dramatic boost in your health and make you feel better and more energetic. If you believe it, then it will be true.