What is the placebo effect?

“Placebo” is a word that has a strange place in our culture, with both positive and negative connotations. The placebo effect refers to your mind's ability to contribute to healthful changes on its own, which, of course, is a positive thing. However, “placebo” is a word that actually means “fake medicine.” So, what is the placebo effect? Let’s find out.

Placebo vs. placebo effect

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Let’s start by getting exact definitions of the word “placebo” and the phrase “placebo effect.” A placebo is a medicinal substance that is given to a research participant that is known by its administrator to have no medical benefit. Common placebos include sugar pills, saline solutions, and sterile water. They are given to a research subject because while they may not have any positive substances in them, they also have none that will harm the person. So why would doctor give a person an inert pill?

Doctors give research participants and patients placebos to see if they can elicit a response known as the placebo effect. The placebo effect is the phenomenon wherein individuals enjoy measurable improvements after being given the inactive treatment.

The placebo effect exists at an interesting intersection of human psychology and physiology where the expectation of improvement manifests itself with real benefits. While this may sound like a success of positive thinking, it’s a bit more complex than that, and there’s a long history of scientific evidence to support it.

History of the placebo effect

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Healers have offered ill or suffering individuals many different concoctions over the centuries, claiming their various benefits. While they lacked the science to demonstrate what worked on a biological level, their expectation was that it would help.

The first documented observations of the placebo effect occurred in 1799, when John Haygarth, a British physician, set out to disprove that expensive metal rods called Perkins Tractors could cure diseases. To do this, he constructed cheap wooden rods that looked identical to the expensive metal ones. He found that four out of five patients reported improvement. He reported his findings in a book entitled “On the Imagination as a Cause and as a Cure of Disorders of the Body.”

The term “placebo effect” was coined in the 1940s when a study on wounded men and the administration of morphine was published. The study found that men who believed they had been administered morphine when they had not experienced the positive benefits anyway.

Use in scientific studies

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As the placebo effect became more accepted in the medical community, it became an important tool for determining the effectiveness of new drugs being tested. It is most used today as a part of a double-blind test.

In a double-bind test, two groups of patients are separated. One is administered the new medicine designed to aid their affliction, and another is given a placebo. In a double-blind test, the doctors administrating the medicine also are unaware of whether they are giving the patient the real drug or the placebo so that no outside bias can skew the results of the test.

If the drug being tested yields measurably better results than the placebo, the drug is understood to be effective and is more likely to be approved for treating patients.

The nocebo effect

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For all the positive elements of the placebo effect, there is another side to this coin, which is referred to as the nocebo effect. In the nocebo effect, a patient’s belief that the consumption of a food or medicine has a negative effect ends up having that effect, even though it cannot, in reality, have that effect.

One recent example of the nocebo effect is in the recent gluten-free fad. Because some people have developed the expectation that consuming gluten will make them feel uncomfortable, it does when they consume gluten — even if they do not have true gluten sensitivity.

The human mind is an amazing thing, and the power it has to help our bodies heal is not to be underestimated. For all the effects that placebos have produced in modern medicine, there are still many elements of it that researchers don’t yet understand.