Science Corner

What Exactly Is the Placebo Effect?

the placebo effect: what causes it?

We’ve probably all heard of the placebo effect, but what is it, and how does it work? For something that happens regularly, it’s not all that well understood.

A placebo is any substance that’s not intended or expected to have any therapeutic effect. Ethically, it generally wouldn’t be considered acceptable to give a patient a placebo in clinical practice, since there would be no informed consent.

Placebos are very useful in research studies, though. As part of the consent process to enrol in a study, participants would be informed that they could potentially receive a placebo or an active drug, but they wouldn’t know which. In a “double-blinded” study, neither the patient nor the researchers dealing with them would be aware of whether the patient received the active drug or a placebo. Wikipedia says that a doctor named Louis Lasagna helped to make placebo-controlled clinical trials the norm in the US, and I must say, I’m somewhat tempted to change my last name to Lasagna.

Professor Ted Kaptchuk, a placebo effect researcher at Harvard University, says:

“The placebo effect is more than positive thinking β€” believing a treatment or procedure will work. It’s about creating a stronger connection between the brain and body and how they work together,”

Harvard Health Publishing

I think that’s a very interesting way of framing it.

The effects from placebos

When there is a placebo benefit, it tends to be in terms of subjective symptoms rather than a change in underlying disease processes. Pain is the most common type of symptom that responds to placebo. It’s not that pain isn’t real, but the way it’s experienced depends on how pain signals are sent up to the brain, and what the brain then does with them.

For people with cancer, a placebo isn’t going to change the disease process and certainly isn’t going to cure their cancer, but it may help lessen side effects like fatigue and nausea from cancer treatment.

Placebo can also help with stress-related insomnia. An interesting study cited by Wikipedia found that people believed that they were sleeping better while taking a placebo, but objectively, there was actually no change in their sleep.

Placebos can also be associated with negative effects, which is called a nocebo effect. This doesn’t seem surprising, given how problems in the head can wreak havoc on the body.

What’s behind the placebo effect

Some of the benefit from placebos seems to be linked to expectancy. If you expect that something is likely to work, you may start to feel better after taking it. On the other hand, if you expect negative effects, you might be headed for nocebo effects. Expecting pain actually makes the brain more sensitive to pain signals.

Conditioned responses can occur when taking a placebo becomes associated with taking actual treatment. This can happen if, for example, the pill or capsule looks similar to an actual treatment. Think Pavlov’s dogs, where the bell is the placebo stimulus. Similarly, the routine and attention of getting treatment can also contribute to the placebo effect..

Placebo analgesic effects may result from the release of endogenous opioids, and the inhibition of pain signals travelling up to the brain.

Not everyone who improves while taking a placebo is actually experiencing a true placebo effect. Some people may have gotten better due to the natural course of their condition; the fancy term for that is regression towards the mean. Studies looking specifically at the placebo effect might compare a placebo group to a no treatment group to differentiate between the two. When clinical drug trials are done, it doesn’t add any new information about the drug to add a no-treatment arm in addition to the drug and the placebo arms, so the placebo response rates encompass both placebo and regression towards the mean./

Do alternative therapies rely on the placebo effect?

It’s quite possible that some alternative remedies that haven’t demonstrated efficacy in clinical trials may be beneficial via a placebo affect.

It’s also possible that traditional or alternative therapies may exert a physiological effect via a mechanism other than what’s traditionally been claimed. For example, there’s no evidence that acupuncture works by affecting qi, the existence of which hasn’t been proven. However, it does appear to have a therapeutic effect related to the gate-control theory of pain.

The key thing, though, is to make sure that there isn’t an underlying issue that’s going unaddressed because of reliance on something that might just be a placebo. Relying on the placebo effect of psychic surgery to treat a tumour just isn’t going to cut the mustard. Whereas if someone is having reiki done for something like chronic pain, whether there’s an effect via a placebo effect or something beyond that really doesn’t matter that much, since there’s a plausible potential for benefit with little to no risk. The claims just need to match the reality.

As long as no one is trying to trick anyone or make things up, I say bring on the placebo. The brain and body are intimately interconnected in ways science hasn’t fully figured out, so why not take advantage of that as long as there’s no risk involved.


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29 thoughts on “What Exactly Is the Placebo Effect?”

  1. Totally agree to take benefits where possible. It is very true that the mind-body connection isn’t nearly understood so why dismiss the placebo?
    I believe that there is a certain negative view around it, like when you’re helped by a placebo that your condition is also ‘imaginary’ which isn’t the case. Nice post!

  2. Interesting topic. I wonder if some studies could be done that are the opposite of double-blind along side of the more traditional to determine how results end up different depending on the experiment. If people know they’re getting a placebo or the medicine, how does that change things compared to those who don’t know. It might give a more complete picture.

    1. I may be getting this wrong, but I think it has been studied and people have to actually think they’re getting (or could be getting) a treatment for the placebo effect to occur.

      1. There has to be some kind of breaking point as to when it stops being viable, too. Can the placebo effect cure cancer? Why or why not? I bet there’s some way to figure out a correlation between what ailments or type of people respond better than don’t. This is why I’m glad I’m not a researchers at a university. I’d just be setting up this kind of stuff all day long, getting my results and then having no idea what to do with them.

        1. From what I read, placebo can shift perception rather than underlying problems, and its effect is limited to what the brain and body have the capacity to do.

  3. Girrrl, I know allll about the placebo effect. Haha. I used to be slightly paranoid and even thought that my psychiatrists were giving me placebo because my medication would suddenly stop working, but in reality the period in which it *worked* was probably the placebo!

    I’m also studying it a bit in statistics class as placebo is a large part of statistical medical studies, of course. What I’m learning is that there are so many unknown factors in these studies it’s no wonder all medications have such wide ranging effects on different people!

    But, to the point of some of your post, I’ve read snippets before about how the placebo effect might be utilized for therapeutic models. If we could get people to feel better without drugs it would be a positive, right? It also opens up my mind a TINY (emphasis on tiny) bit on the subject of woo-woo healing. Maybe there is something in us that can heal very minor damage or abnormalities. I’m not saying we can will ourselves to regrow a toe, of course, but what if we really could cure depression with the right kind of thinking?

    Now, I don’t think that our current idea of “thinking” fits there because I’m not suggesting you just will yourself to be happy. There’d have to be something deeper to it, like a way to control the way your body regulates things. Everything IS connected so I suppose it’s possible to some extent but I think a lot of that stuff is blocked from our conscious minds so that we can’t mess around with how we breathe or how our heart beats. Haha

    I’m using this grammar and spell checker that Microsoft Edge recommended (just trying Edge for something new, I’m usually a Chromer) and it keeps suggesting I remove words like “maybe” or “possibly” to sound more sure of myself. So I go from proposing an idea to sounding like I’m stating something as a fact. I wonder if every 60 year old on Facebook uses this… πŸ˜‰

    1. I maybe/possibly/actually have never even heard of Microsoft Edge.

      I would be so pleased if the woo woo people would stop saying that their woo woo absolutely/certainly with no possibly/maybe involved works by mechanism X, and say they think it works, but they don’t know how, and it might be placebo. The grammar checker would say that sentence was far too long, but I’m fine with that.

      1. Edge is the rebranded internet explorer. It works more like Chrome than IE did and so far, so good. I think the people who claim it’s terrible have never actually used it and are just against Microsoft for reasons.

  4. Totally agree. If I took something that improved my anxiety, I wouldn’t mind if it was just the placebo effect! The connection between the brain and body is fascinating.

  5. Totally agree. As a Psychology practitioner, Placebo effect is one of the most interesting topics to hear. The human mind is so vast that no one can tell how capable we are to do certain things even tricking its own. Sometimes pain is psychological and we only have to trick our mind in order to remove the pain.

  6. I am Queen Placebo! 😝 and you should change your last name to Lasagna. Maybe first? πŸ€” Love your posts… πŸ€πŸ‘πŸΌπŸ‘πŸΌπŸ‘πŸΌ

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