Why “the Placebo Effect” Isn’t as Magical as You Think

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In case you weren’t aware, I have a Patreon where kind people support the work I do for the videos you can watch for free here on YouTube. For people who pledge $5 or more, I offer a weekly newsletter full of all the stuff that I read about that week that didn’t make it into videos – it’s a weird process, because in order to come up with two different videos per week, I have to read through a bonkers amount of news and published studies and think pieces and social media posts until I find something that I find interesting and that I think I can add a unique perspective to.

Sometimes I start writing about the rejected topics for the newsletter only to find that “Oh, I DO have something more to say about this,” and so it is that a few weeks ago I linked to an interesting overview of the placebo effect that particularly called out research showing that the placebo effect is getting stronger over time. This isn’t news, per se, it’s something that people have been studying for some time, so I didn’t think it was worth a video. I just found it interesting to think about from the perspective that researchers use placebos as a way to test new drugs, and if the placebo effect is getting stronger than that means it’s getting harder for new drugs to be approved, even if they’re effective. Something to think about, but something I didn’t really feel like thinking about too deeply at the time.

But last week I happened to read a New York Times piece about a new article in the Medical Journal of Australia that is very, very critical of how many doctors treat the placebo effect. And the whole thing is so weird and confusing I want to talk about it if only to help myself get a better handle on what’s going on and what I think is right.

The doctor at the center of this anti-placebo push is Christopher Maher, a professor at University of Sydney’s School of Public Health. In the New York Times article, he comes across as extremely skeptical, to the point of what I thought might be denialist, of the efficacy of placebos in helping patients. I thought he had some good points, but I balked at statements like “When placebos work at all, he said, it is through deception, creating an expectation of benefit in the patient’s mind,” considering that we know placebos “work” on babies and pets despite the fact that there’s no way for those groups to even know they’re receiving treatment.

But after I read the Times piece, I went over to MJA’s website and read Maher’s full paper, and I gotta say, I think I’m on his side, here.

Let me back up a bit. “The placebo effect” can be a really weird and confusing idea, in part because it isn’t one distinct thing. It’s a catch-all term for “what happens when we give someone something that isn’t supposed to work?” Researchers use it in order to compare it to the intervention that IS supposed to work, so they know if that intervention is really doing something.

But there are a lot of reasons why a person might improve after being given the placebo that isn’t supposed to help them improve – they might just get better naturally, for instance. Let’s say you have 100 people with a fever. You give 50 of them aspirin and 50 of them sugar pills as a control group to see if the aspirin works. 45 of the aspirin-takers immediately have their fever reduced. 15 of the control group’s fevers go down. Do those 15 people who got better mean that sugar pills help fevers go down? No, because their fevers also would have gone down if you hadn’t given them anything at all.

That’s one of Maher’s big arguments: a lot of research about the efficacy of placebos fails to test the placebos against doing absolutely nothing – not even giving someone a sugar pill. If we don’t do that, if we don’t have a control for our “control,” how do we know if it’s the sugar pill or just the body doing its own thing?

Another possible aspect of the placebo effect is the psychological benefit a person gets from being paid attention to, whether that’s having a doctor be nice to them or spend more time with them, or maybe it’s laying down in a candlelit room and listening to soft music while someone rubs nice-smelling oils on you. That kind of placebo is one that might be able to compete with real pharmaceuticals when it’s addressing something subjective or psychological, like chronic pain or anxiety.

And finally there’s the idea that a placebo is something where if you really believe it works, your brain will somehow convince your body to repair itself without the need for real medicine. That would be really cool but there’s just not a lot of good evidence for it. You can give someone a placebo for their cancer and they might feel less nauseated, but their cancer is still going to be there.

Maher’s primary argument in the MJA piece is that all the “weird cool things” we think we know about placebos are based on kind of shoddy research that hasn’t been reproduced. That includes old standbys that I took for granted, like “red sugar pills are more effective than blue sugar pills.” I have heard that repeated in so many pop psychology books and even by scientists I trusted that I just took it for granted, but Maher writes that “in many studies evaluating the influence of the appearance of a placebo pill, the participants did not consume the pill or have a health condition.”

What??? He gives examples: “One review considering placebo features located nine studies of healthy people (n = 1294) testing the effect of the colour of a placebo pill or capsule and only three studies of patients (n = 166). A common design is that researchers have asked healthy people which pill they think would work best; often not even specifying an outcome or health condition. For example, one study asked 20 young healthy men and women to rank the potency of white, black, blue, red, green, orange and yellow capsules on a scale from 1 (strongest) to 7 (weakest). The effect of the physical appearance of a placebo pill has been tested in a few clinical studies (ie, where patients consumed the placebo pill), but the studies are small and have yielded inconsistent results. For example, one study commonly cited to show superiority of red placebos enrolled 22 subjects, with five subjects taking red placebos.” An n of 5 subjects?? Not super convincing.

He also criticizes the claims that placebos work even when you know they’re placebos (studies like a back pain placebo trial that failed to include a control group that got no placebo at all) and, yes, the idea that placebos have become stronger over time (it’s incredibly difficult to compare two different time periods using completely different datasets due to all the possible confounding factors, and even if it’s true, that doesn’t help doctors who want to know if they should be prescribing placebos today).

Back on the New York Times article, they quote the anti-Dr. Maher – Professor Ted Kaptchuk, director of the Program in Placebo Studies and Therapeutic Encounter at Harvard Medical School and one of the authors of the back pain study that failed to follow up on the control group. Kaptchuck says that the “medical ritual” of a doctor just being kind to a patient is probably the basis for most of the positive placebo effects, to which Maher seems to respond (I say “seem” because this wasn’t a direct conversation so who knows if any of this is out of context or misinterpreted by the NY Times journalist) “that conceiving of the medical exchange in such terms is a regression to a culture in which doctors rely on their authority, rather than science, to treat the patient.”

“They’re acting as if the placebo is this magic potion,” he said. “It is a return to medicine’s dark age.”

I agree with him (now more than ever after reading his piece in MJA) that it’s a bad trend for doctors and researchers to look at the placebo effect as some kind of mysterious unknowable power that we need to harness instead of giving people real medicine. I’ve definitely seen “alternative medicine” quacks try to hop on that bandwagon – when research shows that homeopathic pills are no better than the placebo, their next play is saying “yeah, the placebo effect is amazing and so are our magic sugar pills!” That’s dangerous territory.

But I disagree that that’s a good response to the idea that we should consider the psychological benefits patients get when their doctors are kind and seem interested in helping them. When the average doctor-patient interaction clocks in at around 15 minutes, and so many people are struggling with “mystery” illnesses like chronic fatigue, and especially when so many women and minorities feel that their health complaints go ignored by their doctors, I don’t think it’s a return to the dark ages to suggest that patients would have overall better outcomes if their doctors have more time to spend with them and take more interest in what they’re going through.

Of course, that’s not so much on the doctors as it is on the state of our medical industry, but that’s a discussion for another day. In the meanwhile, this is a good reminder (for me as well as you) to be skeptical of the too-good-to-be-true claims of what placebos can do.

If you’d like to read Maher’s paper and other studies I’ve mentioned, remember that you can always find a full transcript with all the links on my Patreon, linked in the video description below. If you found this video helpful or interesting, please give me a thumbs up and subscribe for more!

Rebecca Watson

Rebecca is a writer, speaker, YouTube personality, and unrepentant science nerd. In addition to founding and continuing to run Skepchick, she hosts Quiz-o-Tron, a monthly science-themed quiz show and podcast that pits comedians against nerds. There is an asteroid named in her honor. Twitter @rebeccawatson Mastodon Instagram @actuallyrebeccawatson TikTok @actuallyrebeccawatson YouTube @rebeccawatson BlueSky

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