What is a Placebo?

Have you heard of a placebo? How about a sugar pill? A controlled trial? These are all terms you’ll hear in science class, in science journals, and also in the news. What are they?

A placebo is something that is almost exactly like something else but isn’t.

Huh?

Technically, a placebo is a treatment that doesn’t have a direct physiological effect, or a direct effect on your body.

It helps to think about how a science experiment is done. Let’s say scientists have invented a new pill that is supposed to cure headaches. They find 10 people with headaches and give each of them a pill. 8 of them say their headache feels better. Does that mean the pill works? Or does it mean they felt better for a different reason? Maybe the headache went away on its own.

Or, maybe just the act of taking the pill made them feel better, before the medicine even reached their system. (It’s happened to all of us.)

That’s called the placebo effect. It’s when something makes us feel better because we think it’s going to make us feel better, not because it’s actually affecting our body. The amazing part is that the placebo effect works even when we know it’s a placebo!

If the scientists wanted to know whether it was the medicine working or just the act of taking the pill, they would have to split the group into two. Half of the people would get the medicine and the other half would get a pill that looked identical to the medicine, but had nothing in it. The nothing-pill is often called a sugar pill, because it has nothing in it but sugar. It can also be called a placebo pill. The group that gets the placebo pill is the control group, and the experiment is now called a controlled trial, because it has the two groups to compare.

Controlled trials are considered the “gold standard” of science experiments. As a result, scientists have come up with placebos for lots of things. There’s placebo acupuncture, were they randomly stick needles into you. There’s placebo medicine, of course, but there’s even placebo surgery! Surgeons will make an incision, but not actually perform the surgery. (Before you start feeling bad for the patients, keep in mind that patients volunteer for these kinds of experiments, and are told they could get a placebo.)

If someone tells you a medicine or treatment or other procedure works, they should have controlled experiment data to back up their claim, or else you don’t really know if it’s the treatment that’s doing the work.

On the other hand, if you’re out of ibuprofen but still have a headache, you can tell yourself a bag of chips will make your headache better, and there’s a good chance it just might.

Sources:

https://www.webmd.com/pain-management/what-is-the-placebo-effect#1

https://www.health.harvard.edu/blog/placebo-can-work-even-know-placebo-201607079926