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The Problem with Placebo

what’s the deal with placebo anyway?

Updated: Jan 14th 2013

Placebo is hands down, one of the single most interesting things in all of science.

Basically, you fake a treatment for an illness (like a pill full of sugar instead of medicine) and the person gets better anyway. That’s pretty amazing, especially when you hear about it for the first time.

This has lead to a lot of rhetoric about “harnessing the power of placebo”. However, when you tease apart what the placebo effect actually is, it becomes a little less exciting.

In this post, we’ll discuss what exactly the placebo effect seems to be – and give some cool examples to show why people are so interested in it.

But then, we’ll make the following case: while the ‘placebo effect’ can (and probably should) be utilized by any healthcare professional as an adjunct to their treatment, there appears to be at least one major problem with giving someone ‘placebo’ as a treatment alone, even if it makes people feel better.


  • Some fun examples.
  • How big of an effect are we talking about here?
    – Studies comparing something to placebo.
    – Studies on the placebo effect itself.
  • What is the placebo effect?
    – Placebo
    – the Placebo Effect
    – the Nocebo Effect
  • Here’s the problem…
    – Disease vs. Illness: what’s the difference?
    – Doesn’t the placebo effect actually speed healing?
    – Why is this important?
  • Yes, the placebo effect is still useful!
  • Conclusion.

Some fun examples

Basically, the ‘placebo effect’ is what you experience when you receive a treatment that you believe is right for your disease or condition. We will elaborate on that later. First – what’s so interesting about it?

Let’s review some experimental results that you might find interesting (a.k.a. mind blowing when they were first published):

For gastric ulcers (those nasty, painful “stress ulcers” in your stomach), four sugar pills a day work better than two sugar pills a day! 1 There was no medication in any of them. Simply getting more “medicine” (or so the study participants believed) made their ulcers heal faster.

“hmmm… the blue ones must make you drowsy, right?”

Crazy? Here’s more – pills are more effective when their colors “match” what they’re meant to do: for example, the same drug (oxazepam) is better at treating anxiety when it’s in a green pill, and better at treating depression when it’s yellow. 2, 3, 4 Since no ingredient changed, it’s clear that the cultural meaning of these colors had an effect on patients expectations – green is relaxing, and yellow is up-lifting.

But it’s not just pills – this happens with more complex treatments as well. And the more complex, the bigger the effect tends to be.

For example, saline (salt water) injections are more effective for pain than sugar pills. Not because the salt water does anything – it doesn’t – but because getting a needle seems like a more dramatic intervention to the patient! 5, 6, 7

Let’s kick it up another notch: surgery.

In one experiment, “sham” knee surgery was performed – which is basically cutting someone open and sticking surgical instruments inside without actually changing anything. The sham knee surgery actually worked just as well as the real procedure for improving peoples pain and function (as reported by the patients themselves). 8

Even sham surgery for angina (chest pain from lack of oxygen to the heart) is as effective as real surgery in making people tolerate more exercise with less pain. 9

Pretty cool stuff.

How big of an effect are we talking about here?

It depends. For example, you could simply give a placebo to a patient with very little information, or you could try to illicit the biggest placebo effect possible on purpose.

1. Studies comparing something to placebo:

how big is the placebo effect anyway?

When a treatment for a disease is first being studied, experiments are usually designed to compare its effectiveness against placebo. In these cases it’s really quite boring – you just gather a bunch of people, tell them they may get either the treatment or a placebo (but they don’t know – which is important), and then you measure their results afterwards. The hope is that the treatment works better than placebo – since any improvement in the placebo group could have occurred with giving them anything.

In these experiments, you’re basically telling them they might get something that doesn’t work. Here, the placebo effect has a small ‘effect size’meaning it may be noticeable, but it’s nothing to get excited about (like “meh, I kinda feel better, I guess”). 10, 11 In fact, some researchers believe a lot of this improvement is just because people usually get better anyway. 12

2. Studies on the placebo effect itself:

However, when people are actually studying the placebo effect itself, trying to find out what makes it stronger or weaker, it’s a different story. For example, in these experiments you may tell the patient: “you are going to receive an agent that is known to significantly reduce pain in some people” – which isn’t a lie (‘some’ could mean 5 out of 1000 people, and statistically ‘significant’ just means it’s not a fluke, but it doesn’t mean it’s a big effect).

When you say things like that – being confident and raising the patients expectations – the placebo effect is up to five times stronger, and has a ‘large’ effect size (like “yeah, I definitely feel much better”). 10, 11


It looks as though health care professionals who are confident and encouraging can raise the expectations of the patient and actually make them feel much better. In this way, it makes some sense to harness the “power” of the placebo effect. However…

What is the placebo effect?

Placebo – a treatment or intervention given to treat an illness – but which has no known active medicinal ingredients (a sugar pill, for example).

Placebo vs. the Placebo ‘Effect’

The Placebo effect – the effect one experiences when receiving a treatment or intervention that is believed to be appropriate for the given illness.

Therefore, you could experience a ‘placebo effect’ from either a placebo or something that actually treats the disease. It doesn’t matter, as long as it seems to be the right thing to do. The placebo effect has to do with the cultural tradition of being treated for an illness, and can be influenced by a ton of different factors. 13, 14 Cultural tradition? Sounds pretty flaky, but the more ritualistic a treatment seems, the more powerful the placebo effect seems to be. This is why it’s also known as ‘the meaning effect’.

There is even an opposite effect:

The Nocebo effect – yup, you can actually feel worse after a treatment that doesn’t actually do anything bad. If you think the treatment will cause harm, you may start focusing on anything negative and blame it on the treatment.

Ever read the side-effects of a medication and start thinking you might have them?

Healthcare professionals can also do this to their patients by using scary words. For instance, telling someone they have a “slipped disc” may cause more harm than good.

Here’s the problem…

If you read the examples above carefully, it starts to become clear that the placebo effect seems to only affect a persons feelings of illness. However, it doesn’t seem to have much of an effect on the underlying disease. 15, 21 For example, the ‘psycho-social support’ has a positive effect on cancer patients feelings of illness, but it does not improve how long they survive. 21

Disease vs. Illness: What’s the difference?

Disease – best refers to an abnormal condition affecting an organism. This abnormal condition could be due to infection, degeneration of tissue, injury/trauma, toxic exposure, development of cancer, etc. This is what needs to be ‘cured’, especially if it’s life-threatening.

Illness – best refers to the feelings that might come with having a disease. Feelings like pain, fatigue, weakness, discomfort, distress, confusion, dysfunction, etc. – the reasons people seek healthcare – and usually the way people measure their success with treatment.

It’s very important to understand that feelings of illness can be vastly affected by many non-disease factors, such as expectations, beliefs, fears, feelings/moods, and culture. Being ill is a very personal experience, and can vary tremendously and be affected by very different things between people with the same ‘disease’. While they obviously relate to each other in very significant ways, it’s important to understand the difference. (read: Disease vs. Illness for more detail)

Why is this important?

It’s important here because it seems the placebo effect doesn’t really affect ‘disease’.

The exception (in a way) are those ‘diseases’ whose mechanisms of development may have caused changes in the persons brain / nervous system, 14 like chronic pain, depression, or irritable bowel syndrome. In these cases, ‘psychosocial’ factors may have been a ’cause’ (or at least a strong contributing factor) of the current condition, and it makes sense to target those issues during treatment.

But that still doesn’t justify giving someone a sugar pill and telling them it’s an effective treatment. That’s just giving a placebo. However, it may justify utilizing the placebo effect, and may even be necessary for such illnesses. For instance, perhaps utilizing the placebo effect for chronic pain patients can reverse the brain changes associated with the condition. It may even be necessary.

But wait!

Doesn’t the placebo effect actually speed healing?

People keep saying this, as if it gives the placebo effect a more objective basis. However, the evidence for this idea is not strong. And even when there does seem to be an effect on the disease process, it’s very indirect. Let’s use an example:

might the placebo effect work by reducing stress and anxiety?

The studies cited above demonstrated that gastric ulcers heal faster with a more dramatic placebo. But there may be very good reason for this: stress. Stress has been shown to cause an increase in stomach acid, and the bacteria H. Pylori (believed to cause up to 90% of all stomach ulcers) thrives in an acidic environment. 16 Since we know that placebo can significantly lower stress, 17 it should be no surprise that placebo can speed ulcer healing. However, this doesn’t mean the placebo (sugar pill) actually killed the bacteria (disease)!

‘Irritable Bowel Syndrome’ is another good example. This condition causing pain and discomfort in the gastrointestinal system is highly related to psycho-social factors, namely stress. 18  Again, it makes perfect sense that stress relief will reduce symptoms. And a recent study reviewing the components of the placebo effect on this condition demonstrated that “the patient-practitioner relationship is the most robust component”. 19 If you have a healthcare practitioner that you trust, and you believe they will help you, you’ll feel better, and you will get better.

Placebos can also significantly relieve pain (as described in the examples above). However, we also know that pain doesn’t always mean there is tissue damage. Pain is another feeling of illness that can be manipulated by many other factors. See the ‘Pain Section’ of this site for more.

Yes, the placebo effect is still useful!

All this stuff isn’t to say that the placebo effect isn’t useful – it certainly is.

If you had pain or stress from a disease, you would want as much relief as you can get. ‘Illness’ is usually the reason people seek healthcare in the first place. As discussed above, it may even be necessary for some illnesses – but this justifies utilizing the ‘placebo effect’, not just ‘placebo’.

If we give treatments that are just placebo, then we might be making people feel better without actually treating their disease. This could be seriously dangerous.

This is why placebo is an area of debate in the world of healthcare ethics.

People are even trying to find ways to give a ‘placebo’ ethically – like in this experiment for example (again, notice all the outcome measures we’re subjective reports on symptoms – not an affect on the ‘disease’). 20 Personally, I find it funny that people are trying to find ways to give an ineffective treatment ‘ethically’. Again, why not simply give an effective treatment, and then utilize the placebo effect on top of that? Win-win.


Is it okay to take advantage of the placebo effect?

Within ethical guidelines, sure. I believe it is.

However, I do not believe it’s okay to take advantage of the patient.

Health care providers need to make sure they are doing everything in their power to treat the disease appropriately. The treatment should have good research to back it up: testimonials and anecdotes are not good evidence. Then the professional can worry about providing the treatment in a way that pleases the patient – to relieve stress and anxiety about their illness.

It should be simple, actually: the treatment should be discussed with the patient so they understand what’s going on, and can agree that this is the best choice for them. Some compassion from a practitioner who is informed, confident, and friendly might be all you need to “harness” the placebo effect.

The science of the placebo effect is very interesting.

In the end, perhaps it should be considered the icing on the cake?

What do you think?

This is a very opinionated topic – and I’d love to see how others feel.

Comment below!

Further reading

All the references below, of course. Especially if you plan to debate the science with me in the comments below.

Bad Science by Ben Goldacre – most of the examples of placebo research reviewed at the beginning appeared in this fantastic book. Read my book review – highly recommended!

‘Why Bogus Therapies Seem to Work’ – this article is a fantastic reminder of why we should be humble in our claims as healthcare professionals, and constantly seek the best evidence available for choosing our treatments.

Science-Based Medicine – this site continues to produce great articles and discussions on topics like this. For placebo specifically, try here, here, here, and here.


1. de Craen AJ, Moerman DE, Heisterkamp SH, Tytgat GN, Tijssen JG, Kleijnen J. Placebo effect in the treatment of duodenal ulcer. Br J Clin Pharmacol. 1999 Dec;48(6):853-60. PubMed PMID: 10594490; PubMed Central PMCID: PMC2014313.

2. Blackwell B, Bloomfield SS, Buncher CR. Demonstration to medical students of placebo responses and non-drug factors. Lancet. 1972 Jun 10;1(7763):1279-82. PubMed PMID: 4113531.

3. Schapira K, McClelland HA, Griffiths NR, Newell DJ. Study on the effects of tablet colour in the treatment of anxiety states. Br Med J. 1970 May 23;1(5707):446-9. PubMed PMID: 5420207; PubMed Central PMCID: PMC1700499.

4. Hussain MZ, Ahad A. Tablet colour in anxiety states. Br Med J. 1970 Aug 22;3(5720):466. PubMed PMID: 5454335; PubMed Central PMCID: PMC1701431.

5. de Craen AJ, Tijssen JG, de Gans J, Kleijnen J. Placebo effect in the acute treatment of migraine: subcutaneous placebos are better than oral placebos. J Neurol. 2000 Mar;247(3):183-8. PubMed PMID: 10787112.

6. Gracely RH, Dubner R, McGrath PA. Narcotic analgesia: fentanyl reduces the intensity but not the unpleasantness of painful tooth pulp sensations. Science. 1979 Mar 23;203(4386):1261-3. PubMed PMID: 424753.

7. GRENFELL RF, BRIGGS AH, HOLLAND WC. A double-blind study of the treatment of hypertension. JAMA. 1961 Apr 15;176:124-8. PubMed PMID: 13708477.

8. Moseley JB, O’Malley K, Petersen NJ, Menke TJ, Brody BA, Kuykendall DH, Hollingsworth JC, Ashton CM, Wray NP. A controlled trial of arthroscopic surgery for osteoarthritis of the knee. N Engl J Med. 2002 Jul 11;347(2):81-8. PubMed PMID: 12110735.

9. COBB LA, THOMAS GI, DILLARD DH, MERENDINO KA, BRUCE RA. An evaluation of internal-mammary-artery ligation by a double-blind technic. N Engl J Med. 1959 May 28;260(22):1115-8. PubMed PMID: 13657350.

10. Vase L, Petersen GL, Riley JL 3rd, Price DD. Factors contributing to large analgesic effects in placebo mechanism studies conducted between 2002 and 2007. Pain. 2009 Sep;145(1-2):36-44. doi: 10.1016/j.pain.2009.04.008. Epub 2009 Jun 25. PubMed PMID: 19559529.

11. Vase L, Riley JL 3rd, Price DD. A comparison of placebo effects in clinical analgesic trials versus studies of placebo analgesia. Pain. 2002 Oct;99(3):443-52. PubMed PMID: 12406519.

12. McDonald CJ, Mazzuca SA, McCabe GP Jr. How much of the placebo ‘effect’ is really statistical regression? Stat Med. 1983 Oct-Dec;2(4):417-27. PubMed PMID: 6369471.

13. Kisaalita NR, Roditi D, Robinson ME. Factors affecting placebo acceptability: deception, outcome, and disease severity. J Pain. 2011 Aug;12(8):920-8. doi: 10.1016/j.jpain.2011.02.353. PubMed PMID: 21816353; PubMed Central PMCID: PMC3150516.

14. Benedetti F, Carlino E, Pollo A. How placebos change the patient’s brain. Neuropsychopharmacology. 2011 Jan;36(1):339-54. doi: 10.1038/npp.2010.81. Epub 2010 Jun 30. Review. PubMed PMID: 20592717; PubMed Central PMCID: PMC3055515.

15. Meissner K, Distel H, Mitzdorf U. Evidence for placebo effects on physical but not on biochemical outcome parameters: a review of clinical trials. BMC Med. 2007 Mar 19;5:3. Review. PubMed PMID: 17371590; PubMed Central PMCID: PMC1847831.

16. Kim YH, Lee JH, Lee SS, Cho EY, Oh YL, Son HJ, Rhee PL, Kim JJ, Koh KC, Paik SW, Rhee JC, Choi KW. Long-term stress and Helicobacter pylori infection independently induce gastric mucosal lesions in C57BL/6 mice. Scand J Gastroenterol. 2002 Nov;37(11):1259-64. PubMed PMID: 12465722.

17. Balodis IM, Wynne-Edwards KE, Olmstead MC. The stress-response-dampening effects of placebo. Horm Behav. 2011 Apr;59(4):465-72. doi: 10.1016/j.yhbeh.2011.01.004. Epub 2011 Jan 24. PubMed PMID: 21272586.

18. Mayer EA, Naliboff BD, Chang L, Coutinho SV. V. Stress and irritable bowel syndrome. Am J Physiol Gastrointest Liver Physiol. 2001 Apr;280(4):G519-24. Review. PubMed PMID: 11254476.

19. Kaptchuk TJ, Kelley JM, Conboy LA, Davis RB, Kerr CE, Jacobson EE, Kirsch I, Schyner RN, Nam BH, Nguyen LT, Park M, Rivers AL, McManus C, Kokkotou E, Drossman DA, Goldman P, Lembo AJ. Components of placebo effect: randomised controlled trial in patients with irritable bowel syndrome. BMJ. 2008 May
3;336(7651):999-1003. doi: 10.1136/bmj.39524.439618.25. Epub 2008 Apr 3. PubMed PMID: 18390493; PubMed Central PMCID: PMC2364862.

20. Kaptchuk TJ, Friedlander E, Kelley JM, Sanchez MN, Kokkotou E, Singer JP, Kowalczykowski M, Miller FG, Kirsch I, Lembo AJ. Placebos without deception: a randomized controlled trial in irritable bowel syndrome. PLoS One. 2010 Dec 22;5(12):e15591. doi: 10.1371/journal.pone.0015591. PubMed PMID: 21203519; PubMed Central PMCID: PMC3008733.

21. Goodwin PJ, Leszcz M, Ennis M, Koopmans J, Vincent L, Guther H, Drysdale E, Hundleby M, Chochinov HM, Navarro M, Speca M, Hunter J. The effect of group psychosocial support on survival in metastatic breast cancer. N Engl J Med. 2001 Dec 13;345(24):1719-26. PubMed PMID: 11742045.

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    18 Responses to The Problem with Placebo

    1. Placebo and the “meaning response” (as Moerman describes it) are fascinating – but I don’t entirely accept your argument that placebo doesn’t have specific effect on disease processes. I recently had the pleasure of attending a conference with Serge Marchand, and Irene Tracey, and another conference with Lorimer Moseley and several other prominent neurobiology researchers in which responses to inert substances (either through the clinical setting, patient/clinician expectations, or similar “nonspecific” effects) were described in Parkinsons, operation of the endogenous opioid systems (negated by naloxone), and functional bowel disorders.

      There’s a lovely review by Benedetti F. Carlino E. Pollo A. (2011) How Placebo’s Change the Patient’s Brain in Neuropsychopharmacology. 36(1):339-54.

      And a nice discussion of factors affecting placebo by Kisaalita NR. Roditi D. Robinson ME. (2011) Factors affecting placebo acceptability: deception, outcome, and disease severity. Journal of Pain. 12(8):920-8, 2011 Aug.

      From my perspective, it’s unethical to deceive a patient, but it IS ethical to examine those aspects of placebo that can be openly employed, such as working with patient expectations, using the environment or context effectively, and also being very aware of nocebic effects. One thing that I found incredibly fascinating from Marchand’s work was a study in which it was found that after having been given an ineffective treatment (ie placebo), later effective treatments were less effective than when the order was reversed (ie an active treatment given first, with placebo given later – in this latter condition, effects when given placebo after active treatment were greater than when placebo was given first but followed by active treatment).
      Fascinating stuff – it suggests we should be careful to prescribe/manage with the most effective treatment first to avoid a nocebic effect on subsequent treatments.

      • Tony Ingram says:

        That is really interesting Bronnie! Thanks for those studies, I’ll definitely check them out.

        Again, I should make it clear that I’m not trying to make any black or white distinctions between disease and illness. And if placebo affects disease, it certainly would be through some sort of neuro-immuno-phyisological mechanisms – which I think are certainly plausible. Still, I don’t think there’s much compelling evidence for placebo reversing disease processes (depending on how you define that).

        But even if it does affect disease, I think a critical question should then be: by how much (i.e. effect sizes on non-surrogate outcomes)? And if so, what disease processes do they affect? Inflammation wouldn’t be exciting, but if it could be shown to do something like slow the spread of cancer, then I’d change my tune dramatically! For now though, there doesn’t appear to be any good evidence that placebo does anything that substantial to a ‘disease’.

        Thanks for the thoughts, and I’m glad you commented so people could see how deep and debatable this topic can be. For now, I just try to simplify things so people can get a “quick and dirty” understanding. Sometimes I fear I may over-simplify, and this may be one of those occasions (I was even kind of nervous making this post). However, I am confident that I presented some good evidence for my rationale.

        • Tony Ingram says:

          I read those articles Bronnie! It caused me to go on another rampage of reading articles, and I have edited and added to my article above. Thanks for the inspiration!

      • Tony Ingram says:

        “… it’s unethical to deceive a patient, but it IS ethical to examine those aspects of placebo that can be openly employed, such as working with patient expectations, using the environment or context effectively, and also being very aware of nocebic effects.”

        Absolutely, and I think that’s sort of what I meant in my concluding statements.

        • Exactly! I think it’s such an interesting area of human behaviour to explore – the more we know, the more we can exploit. Certainly in pain, it’s not just distraction or reduced distress, but is the production of endogenous opioids and downregulation down the spino-thalamic tracts.
          A question I ask my students is: if you’ve been using an intervention for years, getting reasonable results, but recently there has been evidence that it is ineffective, DO YOU STILL USE IT? IT always provokes a lot of discussion!
          And yep, I agree – neuropsychoimmunological/neuroimmunophysiological mechanisms are probably in play. What fun! And the best thing about top-down descending inhibitory pathways is that they’re for free.

    2. Tony Ingram says:

      Updated with numerous citations and a few extra paragraphs.

      Under: why is this important?
      “The exception …”

      In: Doesn’t the placebo effect speed healing?
      “Irritable Bowel Syndrome”

      In: Yes, the placebo effect is still useful!
      “People are even trying to find ways to give a ‘placebo’ ethically…”

      Hope this doesn’t make the article too long, and adds to the general message. Thanks for reading!

    3. Ricardo Cantu says:

      Hello. I’m not a doctor but I have a big question about placebo. Is there any illness or disease in which placebo have NEVER had an effect in the patient? Is there ANY test in which placebo is believed beforehand to be useless? Any medicine tested without a control group? Because if not, then the brain can virtually heal any illnesses or disease, no matter where it is, doesn’t it? I know that there is still a lot of research to do, but it can make you wonder, in my non-physician opinion. Thanks for your answers and opinions.

      • Tony Ingram says:

        I wouldn’t say placebo really ‘heals’ anything, in the true sense of the word. That’s the ‘problem’ with placebo that I describe above. While it makes you feel better, it doesn’t actually fix anything.

        However, this could be very useful in treating pain, especially chronic, where changes in the brain and psycho-social factors are actually the problem. This is still an ongoing ethical discussion.

        But with something like cancer, placebo might make you feel better, but it doesn’t change the disease, or improve survival. (reference here)

        In my opinion, selling something that’s not proven to be effective to a person with cancer is downright predatory. For someone with a bad back, well, it’s debatable.

        • Ricardo says:

          Thanks. But still, if placebo doesn’t fix anything, then why is used a control group for all tests, regardless the type of illness or disease that is being tried to heal? I know that healing cancer is one thing and healing back pain is completely another. Neither I’m saying that medicines are useless (not at all). But if stress and other factors damage your health, then many problems are psychological. Well, maybe I’m just repeating what you said in your post. In your personal opinion, do you think that the brain can actually heal themselves, not only in wounds, but in the development of new cells or whatever? I.E. Can placebo actually heal in your opinion, regardless of the hard evidence? Hope not to bother you a lot. :) (I will use your opinion only as a personal point of view and I will not cite you anywhere.. hehe).

    4. Ricardo says:

      Sorry, a mistake. Do you think that the brain can actually heal the body, not only in wounds…

      • Tony Ingram says:

        I’m sorry Ricardo, I might be misunderstanding you. But I’ll try to answer what I think you are asking.

        1. Why placebo is used as a control when studying any disease/illness:
        No matter what the treatment, you’re bound to get a placebo effect if the patient feels it’s going to be helpful (or a ‘nocebo’ effect if they think its harmful). If you test any possible treatment, it will likely show some positive effects (unless it’s harmful). But those effects may simply be the placebo effect. Therefore, you compare the treatment to a placebo. Since the patient and tester shouldn’t know whether the treatment given is placebo or not, the same ‘placebo effect’ will apply to either. If the treatment is truly effective, then it should perform even better than the placebo. If not, then it should be just as effective as placebo.

        2. Sure, I think the brain is capable of some healing through positive thought / decreased stress & anxiety / etc. This may occur through healing of wounds (such as in ulcers), or in the growth of new cells (as you suggested). It seems plausible, knowing what we know about neuroplasticity. And perhaps the placebo effect elicits such a cascade of neurophysiological events – in fact, I’m pretty sure the Bendetti et al. article cited above describes this.

        However, these effects are limited – they are not “slam-dunk” solutions. They tend to only have effects on subjective feelings of illness, and not disease processes at their roots. The effects are usually small, and not clinically relevant (reference).

        In my own opinion: no, I don’t believe placebo ‘heals’ in the sense of killing infections, stopping the spread of cancer, or even healing wounds (ulcer healing is indirect, as described in the article). I believe it has its value in things like pain, anxiety, and motivation. But overall, “utilizing” placebo is over-hyped, and potentially distracts from the research of other promising treatments.

        • Ricardo says:

          Thank you very much, Tony. I appreciate your time to give me references, to post this article and to answer my questions. Regards.

    5. Jim says:

      This is certianly fascinating stuff and I really appreciate you sharing the knowledge.
      I’ll avoid getting into the finer points of its implications and would like to ask how you relate this to hypnosis. Where do you see areas of overlap and differences in the mechanisms of how it may work? What are your thoughts on its use as a treament (primary or adjunct for physical concerns either disease, illness or both?

      • Tony Ingram says:

        Wow, that’s a brilliant question actually. I must admit, I don’t know a lot about hypnosis, and I’ve been meaning to read more about it. I know it’s been used as a research method. I think it’s one of the greatest examples of the power of suggestion. Wouldn’t be surprised at all if it shared many of the same neurophysiological mechanisms as placebo/nocebo.

        I couldn’t really make much of an opinion on it being used as a treatment for any sort. I suppose my first impression would be that it’s probably the same story, useful for feelings of illness but not necessarily disease. Still, that might be very useful for depression, anxiety, chronic pain… I definitely need to do some research!

        Thanks for the comment Jim!

    6. Aaron Moritz says:


      I am curious about the claim that ‘For example, the placebo effect has a positive effect on cancer patients feelings of illness, but it does not improve how long they survive. 21’

      The study you link to has to do with the effects of group therapy on cancer survival, not placebo. With a little searching, I haven’t been able to find any information either way on this topic (whether placebos can measurably affect cancer outcomes), but I do think you made a mistake in the reference you posted because it definitely has to do with therapy, not placebos, which are two completely different things, I’m sure you will agree.

      • Tony Ingram says:

        Hi Aaron!

        I fixed the sentence to say “psycho-social support” rather than “placebo”. You’re right, the reference has to do with group therapy, and didn’t specifically say “placebo”.

        However, I disagree completely that therapy and placebos “are completely two different things”. On the contrary, expressive-supportive or “talk” therapy does not outperform placebo (http://www.ncbi.nlm.nih.gov/pubmed/22152401). That’s why it has positive effects on illness when not compared to placebo: (http://www.ncbi.nlm.nih.gov/pubmed/11343530), and (http://www.ncbi.nlm.nih.gov/pubmed/11742045 – the original reference).

        What’s interesting is that even when this therapy is not tested against a placebo, it still doesn’t improve cancer survival: (here’s another – http://www.ncbi.nlm.nih.gov/pubmed/17647221). Which, in my opinion, means that not even the placebo effect of talk therapy changes cancer survival. That’s my rationale for using that reference – but I agree the study doesn’t come out and say it directly, so I changed it. Not everyone will agree with that rationale, but I’d have to see some seriously rigorous proof that placebo extends cancer survival before I change my mind. A study like that would make the news.

        I make the case in this article that the placebo effect is a “psycho-social” effect, which has neurophysiological mechanisms that are very real. It’s just that we have to be careful what we trust these effects to do.


    7. wil says:

      this is brillient thank you. i wanted to say researching placebos and knowing abit about hypnosis it is as a sense, of self hpnosis! beliving what we are doing is right and their for it will work, especially if we went to the doctors and he gave me a tablet for an example, a tablet will remove my wart.by knowing in my mind this will remove my wart and i have been told it takes 2weeks to do it. so psychologicaly i know in my mind it will be gone within two weeks because the dotor gave me a tablet to remove it. however, this can be a placebos or real doesnt matter coz we have hypnotised out mind already by beliving it works. if on the other hand we didnt belive it would work, thwn it wouldnt. its strange but everything links together. its hard to explin but put sigmund frued, abraham maslow, carl rogers, and james braid founder of hypnosis. put all these together and you have a derren brown. its like having a child or puppy put you teach and controll your brain and power to minipulate what is and will be doing. its fantatsic but also crazy anmd really hard to understand. does any of that make sense.?

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