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Comment by vitiral | Hacker News Reader

If someone could explain how "the placebo effect" is not just "scientifically proven faith healing" I'd love to hear it.

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It varies a lot. For many conditions, like cancers, the placebo effect is basically random noise (cancers sometimes just reduce or go away on their own, regardless of treatment or even of the appearance of treatment ; we don't know the natural rate of this, because it's unethical to not treat people who you know have cancer). In addition, in non-blind trials, there is a "placebo effect" that amounts to mistakes or lies by those involved in the research in favor of a positive outcome. This is not a real effect in patients at all, just an artifact in the reported data.

Then, for conditions linked to our psyche, including pure psychological conditions but also things like pain, blood pressure, heart rate, nausea, and some others - the placebo effect is more real, but usually temporary. Some people who have been living in some amount of despair at their condition experience a positive surge of hope once treatment starts, and they can ignore the pain, or feel some push to get out of their depression, or calm their anxiety which was exacerbating, say, the high blood pressure etc. This effect almost always tapers off if the treatment is not doing anything more fundamental.

Coupled with the fact that we don't understand how psychological disorders work at the chemical level at all, especially in relation to the conscious mind and interventions on that (e.g. therapy, but also various religious practices), this means it's very hard to account for this without a double-blind RCT.

The problem as I see it is that all medicine is fundamentally trying to find effective scaffolding on the human body, triggering it's own ability to heal. A surgeon can't repair a corpse. What causes the body to heal itself more effectively? I would think this is brutally difficult to study, since it's all subjective.

I think part of medicine is that, but part of medicine is trying to keep you alive despite your body. Or maybe what I'm arguing here is the "body healing itself". But for example, if you have autoimmune disease, or allergies, you want the body to slow down and take it easy because it's harming itself.

sure. How effective is faith/placebo at curing those conditions I wonder?

> they can ignore the pain,

Just to note that on pain specifically, belief that one has been administered a drug can cause the body to synthesise painkillers. This has been most rigorously demonstrated by the fact that these painkilling effects are suppressed by naloxone (an opioid antagonist).

Fascinating

I'm fairly convinced this is not much different than the way that your body will prime itself if it knows you have an alarm going off at a given time. I don't have the paper anymore, but it was shown that your hormone profile will change with just the knowledge of an alarm. Similar results have been found for other drugs and using cues to the body so that it will prime them itself.

I'd love to read more on how this links to the powers of ritual and general routines. Specifically, if I'm not misremembering, it isn't just "belief that one has been administered a drug", but it has to be a drug that you have had before. Or that you have seen work on someone else. Just taking sugar pills does nothing. Taking sugar pills that you thought were the aspirin pills you took last time you were sick can cause the body to react.

> I'd love to read more on how this links to the powers of ritual and general routines. Specifically, if I'm not misremembering, it isn't just "belief that one has been administered a drug", but it has to be a drug that you have had before. Or that you have seen work on someone else. Just taking sugar pills does nothing. Taking sugar pills that you thought were the aspirin pills you took last time you were sick can cause the body to react.

Not always, you can see effects from open placebos, where you tell the participant that they're getting a placebo but placebos have been clinically proven to reduce pain.

It even seems to work when you warn participants in the consent docs that you may lie to them (authorised deception).

I agree that it's probably a broader effect than just sugar pills, it should probably be called expectancy effects.

Benedetti et al have done a load of work on recovering surgical patients that suggest that many, many drugs (including valium) mostly work based on these kinds of effects. Its a fascinating field (and what I did my PhD on).

The placebo effect is not a single thing. That is, there are ways of amplifying the effect and minimizing the effect. For maximum effect, treatments ought to be designed to take advantage of the placebo effect to the extent possible. That’s because placebos have low side effects and are often very effective. However, this creates some challenges — how do you test which placebo effect works best? What do you use as a placebo? It’s not that hard, really — just use a placebo with less of a placebo effect.

Niacin was used as the placebo for Timothy Leary’s Good Friday experiment [1], where he randomly dosed catholic monks on psilocybin. Unlike a sugar pill, Niacin creates some facial flushing — so you do feel something. But it would be very clear eventually that you didn’t get the psilocybin. But that doesn’t negate the findings of the experiment.

[1] https://en.wikipedia.org/wiki/Marsh_Chapel_Experiment

Sure, for those conditions that have subjective components (e.g. pain, mood) or where there is more or less direct conscious control of the condition (e.g. heart rate, BP), you can vary the strength of such effects.

But in many other conditions, you can't, because that kind of placebo effect is just noise. For example, you can't vary the effectiveness of placebo effects in antibiotics studies (though you may be able to reduce certain side effects like headache or nausea).

Well, you can if there is a mental connection to the immune system. E.g. attitudes toward life and toward disease seems to affect outcomes in cancer patients. And placebos can affect that.

That's true, but I'm not sure such a link has ever been established. Is there any study that has found measurable variance in cancer or infection outcomes based on differences in mental outlook?

Here’s an article that speaks to this: https://www.onclive.com/view/markman-column-optimism-plays-a...

In short, yes! Mental outlook has a big effect on outcomes. It won’t cure you, but it will improve your physical outcomes.

This is the meta analysis they refer to: Rozanski A, Bavishi C, Kubzansky LD, Cohen R. Association of optimism with cardiovascular events and all-cause mortality: a systematic review and meta-analysis. JAMA Netw Open. 2019;2(9):e1912200. doi:10.1001/jamanetworkopen.2019.12200

Fascinating, thank you for sharing this, I'll take a deeper look.

I think part of it is regression to the mean. Like, your body heals itself naturally from many things. Say you get a cold. For most people at some point it'll heal. If you have a group of people with the cold, and try to determine how effective vitamin C or zinc or COLDKILLER777 is, you can't just give it to them and say "look, they're healed", because they would heal naturally. You have to prove that they feel less symptoms or heal faster than people in the same circumstances that don't receive the same molecule.

I also remember some similar stuff for back pain and surgeries. In that context people were seeking treatment when their back issues peaked, and the question was, when you take the cohort of people that had back surgery and the cohort of people that didn't, did the back surgery make a difference? Because some people healed naturally.

I don't know if this is true in that specific context, but to take a more pedestrian one, I've had lots of small cuts, burns and things like that during my life, and they all healed.

The placebo effect controls for all of these factors, and is entirely real. It's the reason placebo control groups exist in the first place. If the placebo effect was just statistical noise, then you could greatly simplify trials by just taking a random group of people as the control, and do away entirely with trying to hide from both patient and technician who is taking the drug - because it wouldn't matter at all.

You can see the opposite effect with the less well known nocebos [1]. People can experience objectively measurable side effects (such as bloating) that are in no way associated with a treatment, but that a patient believes to be a side effect. It can even be fatal. The article references aboriginals who will 'curse' one another resulting in the victim rapidly dying, because he believes so strongly that he is going to die! A similar thing in contemporary medicine has been observed with those who receive a fatal prognosis of cancer with them ending up dying long before there is any way the cancer could have killed them.

[1] - https://en.wikipedia.org/wiki/Nocebo

Faith healing has heavy religious tones. Yet not everyone who responds positively to a placebo is religious. So, it feels sort of weird to call the placebo effect some form of faith healing.

I guess it depends on how you define religion. I think that we can have faith in anything - science, your doctor, etc. that could work in a similar fashion to religious faith.

This is specious. Religion is clearly centered around the spiritual and physical beliefs about the world and the practices of a specific group.

Trusting your doctor is usually more along the lines of an educated guess due to the necessity to act without perfect information.

That was the point of the question. Wouldn't you say "placebo" has heavy intellectualizing overtones?

No, I wouldn't.

Why not when you feel the opposite about "faith healing"?

Placebos doesn't heal. They just seem to relief some symptoms typically self reported, like pain, but the underlying cause is still there.

The tricky thing about that (which isn't false, per se) in the context of mental health is that "relieve some self reported symptoms" can actually be sufficient treatment. As with many sorts of pain, if the patient feels better, _they are better_ in a meaningful sense. Whether it's "real" is sort of beside the point, especially if the problem is that they are (for example) too miserable to do normal life things that would stop them being miserable and the placebo is sufficient for them to feel as if perhaps they could.

Also, relief of emotional discomfort can help the patient adopt more behaviors that are associated with positive changes in mental health, such as exercise and pursuing social engagements.

Not necessarily. The placebo effect is the kind of thing where you might have trouble at first telling if your symptoms are improving or if you’re just having a “good day” or an “easy week”, and that confusion can even last a month or two during which you’re over-observing your internal state and feeling hopeful that “maybe this is what getting better feels like”. But in the long term you often figure it out.

I had a placebo effect recently when switching ADHD medication to get around the shortages. For a couple months I thought there was a chance my new meds might actually be better, they definitely felt different (and still do). But six months in it’s clear to me that I’m struggling with productivity more than I was before I switched (though less than when I was off meds).

I’m just one guy, but I’d guess this is why doctors don’t just prescribe placebos all the time as actual therapies (well, that and they’d lose credibility which would then destroy any remaining placebo effect).

Warts are overall very responsive to placebos.

My M.D. father, family practice in the army, later a pathologist, would do what he had learned from other doctors: Put some dye in toothpaste, put it on the wart(s), bandage it, talk about what a miracle cure it was etc. He said it worked the few times he tried it.

FYI, food dyes are not inherently inert, and are capable of having antifungal, antiviral, and/or antioxidant effects. Quick examples:

https://link.springer.com/article/10.1007/s10068-011-0002-0

https://www.purdue.edu/newsroom/releases/2020/Q3/new-approac...

The pigments fungi produce are so essential to their survival, they can’t defend against pathogens when they are gene edited to stop producing them.

Toothpaste is also far from an inactive substance, there are definitely plausible mechanisms at play with the toothpaste and dye mix that could help suppress/resolve a wart. It would be worth a study, though I’m not sure what one would use to try and achieve a truly inert placebo for comparison without first figuring out what doesn’t work.

Nothing to do with placebo, it's the covering that did the trick, not the talk about miracle cure.

(I discovered this myself when I was a kid, any proper airtight cover is likely to get rid of it, YMMV)

Stress negatively affects the outcome of patients, why couldn't the opposite be true?

Mental health conditions are typically defined by a collection of symptoms though, aren't they? I am not suggesting there is no underlying cause, but our ability to detect and quantify that cause is lacking, so defining disorders based on a collection of symptoms is what we are mostly left with in many cases.

It is but it’s a very finicky treatment.

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