How does the Placebo effect work?


How can we practice this effect and what can it cure?

In: 5

You take something that has no proven ability to help you however your belief that it will help you causes it to help you.

For example: you have a headache. You take a sugar pill believing it is a normal pain killer and your headache still goes away. That sugar pill is referred to as the placebo. A placebo doesn’t work for everyone or all the time.

Interestingly, the bigger the placebo the more likely it is to work. For example if you take an annoyingly big sugar pill thinking it is a pain killer it’s more likely to remove your headache than a small easy to swallow sugar pill.

Edit: to add to this, it’s important in new drug testing because sometimes the act of being told you need to take something can cause the symptoms to go away. As such in clinical trials you need to compare the real drug to a placebo. If a placebo works 50% of the time and the new drug also works 50% of the time it’s not actually working. If a placebo works 50% of the time and the new drug works 100% of the time then the drug does have an effect beyond just the placebo of taking something drug-like. There is more to it but it’s beyond the ELI5 scope provably and more into scientific testing rather than actually speaking about placebos.

there is evidence that your mental state affects your immune system, your metabolism and your hormones, all of which affects healing. And it can make you feel better, and less likely to see a doctor.

placebo effect can help a lot with inflammations, reduce perceived pain, and accelerate healing of injuries.

Placebo effect cannot set a broken bone, but it can help it heal faster.

It cannot prevent infection, but it can reduce the symptoms and speed up recovery, at least for minor infections. It will not help you overcome rabies or AIDS, you need serious medication for that.

You create the placebo effect by convincing the patient that their treatment will work. It could take scientific evidence, medical or magical rituals, high price, etc.

I’m going to throw some water on the fire about the placebo effect. A lot of the early work on placebo was not careful about what was being studied (placebo *effect* or placebo *control)*, and there isn’t very good evidence it works for actual injury or illness, but it does work for subjective experience.

When you look through reviews and meta-analyses, most studies list the outcomes as the subjective stuff: pain, emotionality (e.g., depressive feelings, anxiety), subjective self-report of side-effects and some symptoms. Some side-effects are literally caused by placebo, termed nocebo since they’re bad, so it’s not surprising placebo can stop them.

There aren’t many studies demonstrating they help with physical ailments, like healing a physical injury. Also many people confuse placebo *effect* with placebo *control*, and they are not the same. if you look up placebo effect, you will find studies that refer to it as placebo effect, but it’s mixing together potential placebo effect with lots of other processes (e.g., natural healing, spontaneous remission of disease).

Concrete example, you get a cold and get placebo. You heal. We can’t say the placebo *caused* the healing. You could have just healed naturally. Or if its cancer, cancers do spontaneously go into remission.

In conclusion, the placebo effect is real and important, but it’s not proven to be as profound as some early studies made it look.

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Oh yeah, and the answer for how it works for what we know is by modifying expectations. At least that’s the hypothesis, and there is some evidence for it. Some argue it’s by classical conditioning: we have associations in our memory of responding to certain stimuli (e.g., a pill) in certain ways (e.g., feeling better), and so we automatically do.