Are you a Harry Potter fan? If so, you might recall the following storyline from Harry Potter and the Half-Blood Prince.
Harry’s friend, Ronald Weasley, is an enthusiastic hobby sportsman with considerable talent on the Quidditch pitch. When playing the wizarding game competitively, however, Ron suffers from terrible nerves. His confidence tends to crumble under pressure, resulting in insufferable moodiness and less-than-stellar performance. His best pal, Harry, does what he can to remedy the situation. He uses confidence-boosting praise, motivational speeches, and extra training… all to no avail. Then, in a final attempt to help his friend and save the team, Harry tries a new strategy.
At breakfast before the next big game, Harry puts on quite the show while tipping several drops of highly prized but strictly regulated lucky potion into Ron’s cup of pumpkin juice. Ron, believing himself to have ingested a magical performance booster, suddenly sports a much-changed mindset. Overflowing with optimism and confidence, he interprets random flukes as lucky omens. During the subsequent game, he rises to new heights of performance, contributing to a comfortable win for the team.
Only when the game is over does Harry let him in on a secret. No lucky potion had ever touched Ron’s lips. Harry had merely pretended to add the lucky potion to his drink. Consequently, Ron’s impressive performance during the game was his personal achievement alone and had resulted from a change simply in attitude and expectations.
The above example demonstrates the surprising power of placebos, that is, substances without any actual therapeutic benefit that end up improving a person’s health or wellbeing simply by changing their mindset. When receiving a placebo drug that looks and feels like actual medical treatment, patients tend to generate positive expectations, anticipating a subsequent improvement of their symptoms. These expectations are so powerful that they may result in measurable physiological changes in the body. For example, the ingestion of placebo drugs can affect the levels of chemicals, such as the neurotransmitter dopamine, in the brain. These biochemical changes, in turn, may result in significant symptom relief. A placebo-induced increase in dopamine, for instance, may improve symptoms of Parkinson’s Disease, such as tremors and muscle stiffness. Hence, just like in the example of Ron’s miraculous performance recovery, positive patient expectations may have the power to bring about much-desired change.
The placebo effect is a well-documented phenomenon that many patients are likely to have experienced in the past. However, recent research highlights a few surprising facts that are less well known.
Did you know that placebo drugs can have side effects? Just like real medicines, non-active drugs can cause unpleasant physiological consequences. For example, if a patient believes they are taking a real drug that is known for side effects of stomach ache and diarrhea, their mere expectation could produce these undesirable symptoms when taking a placebo drug instead. This phenomenon is referred to as “nocebo effect.”
Placebo and nocebo effects are two sides of the same coin. Both describe the powerful influence of patient expectations on subsequent health outcomes. However, while the placebo effect refers to positive effects on patient outcomes, the nocebo effect refers to negative effects.
2. The placebo effect gets stronger over time.
Placebo substances have an important place in research. Most clinical trials that test the effectiveness of new medicines include a so-called "placebo group." Patients who are assigned to this group receive a placebo substance that looks just like the “real” drug. By comparing patient results from the real medication group with those from the placebo group, researchers can tell whether patient improvements were caused by the medicine or merely by the mindset. This helps them to evaluate the new drug’s overall effectiveness.
The results from decades of placebo-controlled drug trials revealed a curious phenomenon regarding the placebo effect. Over the years, placebo drugs appeared to become more powerful. For example, a study comparing the effectiveness of placebo drugs and active drugs for pain relief between 1996 and 2013 found that active drugs started off with a large advantage over placebo drugs. They produced almost 30 percent more pain relief than their non-active counterparts. This difference, however, decreased over time. By 2013, active drugs only produced 8.9 percent more pain relief compared to the placebos, even though active drugs had remained stable in their power to ease pain. This led researchers to conclude that the placebo effect has increased over time.
What is the reason for this strange phenomenon? One possibility is that today’s patients are simply more aware of the placebo effect. When participating in drug trials, they may recall previous evidence on the power of placebos. This could lead them to expect symptom improvement independent of the trial group they’re part of—be it a real drug or placebo. Researchers have thus suggested that increased knowledge leads to even higher expectations, which may further boost the power of placebos.
Recovering from illness through the mere power of the mind—doesn’t that sound excellent? Let’s cut down on conventional medicines and give all patients sugar pills instead, right? Well, it isn’t quite so simple. The reason why placebos work is that patients believe they’re taking actual drugs. Consequently, doctors have to deceive their patients about the nature of the medicines they are prescribing.
Do you enjoy being lied to? Probably not! Luckily, new research points to ways in which the moral issue of deception could be overcome. Studies suggest that even if openly referred to as placebos, “dummy drugs” could still yield patient benefits. The effectiveness of such “open-label” placebos, however, may depend on the way these placebos are described to patients. A study on irritable bowel syndrome, for example, highlighted the importance of informing patients about the proven effectiveness of some inert substances by activating “mind-body self-healing processes.”
Recent research on the placebo effect sheds light on complex psychological mechanisms that affect both body and mind. It is evident that people’s mindsets are a key prerequisite for change. Author David Robson explores this argument in much more detail in his latest book The Expectation Effect. He suggests that the placebo effect is only one particular example of how expectations may transform a person’s life.