3 ms·

It’s really difficult to untangle the placebo and nocebo effects. I was recently surprised to learn there are studies showing placebos can be effective even whe

It’s really difficult to untangle the placebo and nocebo effects. I was recently surprised to learn there are studies showing placebos can be effective even when people are told they are taking a placebo. Ie literally telling people, “take this pill every day, but please understand it’s a placebo and has no active ingredients whatsoever”. And yet, their symptoms improve. The theory is that the subconscious mind acts on some information (white-coated professional giving me a medicine) without being fully affected by the conscious mind’s knowledge that the pill ought to do nothing. It’s even possible that the negative attitudes of your pharmacist family members toward the medications their patients are taking are affecting their efficacy!

jtriangle 3y ago
You're missing the part where they told participants what the placebo effect was, and that taking the placebo would make them feel better in spite of it having no active ingredients, and it did indeed do so.
cheald 3y ago
"Suggestible You" by Erik Vance explores this phenomenon, and really turned me around on placebos. I'm, generally speaking, not particularly susceptible to placebo effects, and always kind of (arrogantly) chalked placebo effects up to people just being gullible and wanting to see something that wasn't there. It turns out there are actually genes that might be responsible for the physical impact of the placebo effect in the brain. There's an enzyme - catechol-O-methyltransferase - which is coded for by the COMT gene. This enzyme catalyzes the metabolism of dopamine in the brain. COMT has three common variations - AA/AG/GG - which substantially alters how effective the enzyme is at metabolizing dopamine. AA results in significantly reduced enzyme activity, which can result in dopamine built-up in the brain, which results in increased sensitivity to stress, anxiety, and pain, but comes with the bonus of enhanced cognition, motor skills, and memory. AA genotypes also tend to be "placebo responders", while GG genotypes tend to be non-responders. This tends to imply that placebo responsiveness isn't purely psychological, but physical - and indeed, it turns out that in AA "responders" you can turn off the placebo effect by administrating naloxone (which works by binding to opioid receptors)! This has really interesting implications for pharmacological research, too - if there are people who are genotypically predisposed towards or against placebo effects, then a drug trial that stacks responders in the trial group and non-responders in the placebo group which would produce a drug efficacy signal that could be just the placebo effect.
- jrgoff 3y ago
  Is the COMT gene stuff discussed in "Suggestible You"? I recently learned I have the AA variation and from what I understand so far, it seems like it might be an explanation (or at least part of one) for why I am so sensitive to a number of vitamins and medications. I hadn't heard about the placebo related thing. But anyway, I am interested in continuing to learn more about it (it has been somewhat difficult for me to find digestible information about it online) so might look into that book if it discusses it much at all.
  - cheald 3y ago
    Yup, it's discussed extensively, predominantly as "val/val" (GG) and "met/met" (AA).

jtriangle 3y ago

You're missing the part where they told participants what the placebo effect was, and that taking the placebo would make them feel better in spite of it having no active ingredients, and it did indeed do so.

cheald 3y ago

"Suggestible You" by Erik Vance explores this phenomenon, and really turned me around on placebos. I'm, generally speaking, not particularly susceptible to placebo effects, and always kind of (arrogantly) chalked placebo effects up to people just being gullible and wanting to see something that wasn't there. It turns out there are actually genes that might be responsible for the physical impact of the placebo effect in the brain. There's an enzyme - catechol-O-methyltransferase - which is coded for by the COMT gene. This enzyme catalyzes the metabolism of dopamine in the brain. COMT has three common variations - AA/AG/GG - which substantially alters how effective the enzyme is at metabolizing dopamine. AA results in significantly reduced enzyme activity, which can result in dopamine built-up in the brain, which results in increased sensitivity to stress, anxiety, and pain, but comes with the bonus of enhanced cognition, motor skills, and memory. AA genotypes also tend to be "placebo responders", while GG genotypes tend to be non-responders. This tends to imply that placebo responsiveness isn't purely psychological, but physical - and indeed, it turns out that in AA "responders" you can turn off the placebo effect by administrating naloxone (which works by binding to opioid receptors)! This has really interesting implications for pharmacological research, too - if there are people who are genotypically predisposed towards or against placebo effects, then a drug trial that stacks responders in the trial group and non-responders in the placebo group which would produce a drug efficacy signal that could be just the placebo effect.

jrgoff 3y ago
Is the COMT gene stuff discussed in "Suggestible You"? I recently learned I have the AA variation and from what I understand so far, it seems like it might be an explanation (or at least part of one) for why I am so sensitive to a number of vitamins and medications. I hadn't heard about the placebo related thing. But anyway, I am interested in continuing to learn more about it (it has been somewhat difficult for me to find digestible information about it online) so might look into that book if it discusses it much at all.
- cheald 3y ago
  Yup, it's discussed extensively, predominantly as "val/val" (GG) and "met/met" (AA).