Does placebo work or not? And what is nocebo anyway?

The placebo effect has become a common concept in recent decades. But what exactly does it mean? And can a placebo or nocebo actually have an effect?

The placebo effect: a positive result that results from the belief that an effective treatment has been received. In other words, if we think something works , it may work. This mechanism was discovered by accident by an American doctor, Henry Beecher, during World War II. Due to a shortage of morphine, he administered saline solution to wounded soldiers during surgery. He noticed that the soldiers experienced the same pain relief, even though the saline solution itself had no painkilling effect.

Since then, much research has been done into the power of the placebo effect, both in medical science and in top-level sports. For example, it turned out that the tremors in patients with Parkinson's disease decreased significantly when this group was given a placebo pill. When a brain scan was made, it was visible that the production of dopamine was stimulated by the dummy pill, the same hormone that the common Parkinson's medication Levodopa is aimed at.

But surgical research also shows how powerful the effect of our brains can be. In a Finnish study, patients with a torn meniscus were divided into two groups. One group underwent the standard surgery, while the other group received a sham operation in which the knee was opened but no intervention was performed. The surgeons pretended to operate. Remarkably, both groups improved equally in function and pain.

Impressive placebo effects have also been observed in top-level sports. For example, cyclists were found to cycle faster after taking a dummy pill – even when they knew it contained no active ingredient. Mountain climbers were less likely to get altitude sickness when they thought they were using active oxygen, while in reality the bottles only contained normal air. And this while they were at altitudes of up to 5,500 metres, where the oxygen content is halved.

That our brains can positively influence the body is clear. But it also works the other way around. The nocebo effect – the counterpart of the placebo effect – shows how our beliefs can actually lead to complaints. This became clearly visible in the same study with the mountain climbers. Some of the participants were told that they would probably get headaches due to the altitude. And indeed: this group reported headaches considerably more often than the group that was not told.

Furthermore, there are known situations in which entire groups of people develop the same disorder or side effect after people in the environment or on social media experience certain symptoms. These cases are described as mass psychogenic illnesses. As far as we know, they have no demonstrable physical explanation. We can therefore think ourselves nauseous, weak or ill.

We do not know exactly how the effect works. But it is evident that it works. Within medical science, the placebo effect is therefore a point of discussion, because if it works, why do we not apply it as a treatment? According to Ian Harris - professor of surgery at the University of New South Wales - we should be careful with this: "If we embrace placebo as a treatment, the only barrier between alternative and regular medicine disappears."

On a personal level, awareness of both placebo and nocebo is more than enough. You might even benefit from them. Because whether you think you can do something, or you think you can’t, you might be right.

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