Jono (00:01.378)

Welcome back to the Bite Me Nutrition podcast, Food Groupies. That's what I'm calling you from now on, Food Groupies. Just gotta deal with it. If you don't like it, please find our postal address on Google and send me an analog letter about it. But today we're gonna be talking about the placebo effect, which is, I think, a really, really fascinating topic and a really, really important topic for us to get our heads around because it can help give you some extra context towards

that you can put towards when you're evaluating maybe something you've heard, claim someone's made, and that may not just be a claim on social media, it could literally be a friend or a family member who's talking to you about their experience with a supplement or a diet or some kind of radical protocol. And particularly if their experience goes completely against quote unquote, the weight of the evidence. Now,

I'm certainly not suggesting that science knows everything. And there's, I'm sure going to be things as we move forwards that, you know, we find that, that person was experiencing that result because of this thing that we didn't know about, right? Cause it was a true effect. However, if we look into the placebo effect, I think you'll find that a huge majority of those experiences can be explained away. Explained away is a bit rude, but can be explained by the placebo effect. So,

I'll take you through what a placebo is, talk about something, a few things about it that are interesting, share with you a few crazy examples from the evidence from the literature of the placebo effect and what we've seen. And then also just kind of tell you why it's important and explain how you can use this information to make a better, more informed, honestly, just a more critical appraisal of all of the claims that you might hear someone make. So a placebo is essentially

some kind of, it's something that will be perceived as true treatment, right? That could be a supplement, a medication, an exercise protocol. It could be acupuncture. It could be a whole host of things. That is the intervention. And a placebo is a version of that, which is designed to actually have no effect. Okay. So the common, the most common example is a sugar pill, quote unquote. So you're testing this supplement to see if it has an effect and you're comparing it with someone getting a sugar pill. just for,

Jono (02:23.916)

very, very basic study design in the case of randomly controlled trials. What we do is not me, I'm not smart enough to do trials. The people who are smart enough to do trials, we typically have two, I just said we again, I'm just trying to be smart by association. There are typically two groups in that study at least, but there's always at the very least, well, hopefully there's often a control group. Now the control group is, they are designed to get no intervention.

you know, because we want to test to see if the group that's getting the supplement or the medication, what have you, is seeing an effect. And if they're seeing an effect, maybe then the supplement is helpful, or maybe then the exercise is helpful, and so on and so forth. Now, the issue with that is you can't just tell people, you're getting a supplement and you're not because of the placebo effect. Everyone who's getting the supplement will think, well, they'll have this bias towards I'm going to get better results because I've got the supplement versus the person who's, well, I'm not getting anything, so nothing's going to change for me.

So we use a placebo to make everyone unsure of whether they have the supplement or not. That's the goal of the placebo to kind of even the playing fields, right? And oftentimes in what's called a doubly blinded trial, the people taking the supplement or the placebo don't know which one they're getting and the people doing the research don't know which one the participants are getting, right? So they're kind of measuring everything and everyone's going in even. Now there's a whole host of other things you need to worry about with study design, which I won't go into now, i .e.

it's hard to have a control group sometimes for like a supplement because for example, you can't test a control group with no vitamin D levels and give someone a vitamin D supplement. The people in the control group are still going to have some vitamin D in different amounts and so on and so forth. But just for argument's sake, it's probably a bit simpler to think of it from like a study of a supplement where like we don't have naturally occurring ashwagandha for example. So you'd have a group getting the ashwagandha supplement and a group

getting the placebo supplement, but both pills would look exactly the same, so no one would know what they're getting. A fun one I found out about a while ago was they use toothpicks in acupuncture studies. So it's called sham acupuncture, where essentially the person doesn't know, because it's pretty hard to, how can you convince someone they're getting acupuncture if they're not? Apparently you just poke them with a toothpick. there's all, I'm sure there's lots of other creative ways that people have used a placebo in the literature. Anyway.

Jono (04:48.318)

One really, really key thing here is this idea of expectancy. We see if someone expects this thing to work, we're far more likely to see them actually get a result, regardless of whether that result was actually due to the thing that they've swallowed or the diet they have followed. Whoa, that rhymed. That was cool. Take that Dr. Zeus. I'm so distracted now. What was I saying? Yeah, right. If they expect that this thing will work.

it's there's already a high chance that it's going to work. And now the really crazy thing about expectancy is it's not just if the individual expects that because they've willed themselves to think so what's probably far more likely is they have been reading lots of things. They have been hearing lots of people they have been following lots of people they've been seeing groups, you know, social communal groups on the internet talking about certain diets and certain supplements that is amazing and have changed their life. And I'm sure those groups have no financial

gain or interest or anything like that. He says incredibly sarcastically, but because this person has come in and seen this overwhelming amount of evidence to show that this thing works, when they start the thing, they are already going to be expecting it to work. That power of expectancy is already there. So that's one reason why we need to be very careful with how we approach this, right? Because in that scenario, there is no control group. There's no blinding, right? Like the blinding, know, participants not knowing what they're doing and,

scientists not knowing what they're doing, not knowing what they're doing, not knowing who's getting what intervention. So there's no scientific method there. It is just kind of all anecdotal. And that's one of the reasons why the scientific method is so important because it can, with some clever work, kind of negate the impact of the placebo effect to a degree, right? And so we've seen pretty crazy examples of this in the literature. There's a study where a was told,

There was a group that said, we're going to train, we're going to exercise. Some of you get anabolic steroids and some of you don't. The thing was none of them got anabolic steroids. Just one group thought they did. And that group, I think it was out of like 75 % of the exercises, they performed way better, statistically significantly better than the group that didn't, right? Even though everyone was taking the same stuff, which was nothing. We've seen studies where our cyclists were given caffeine, which we know caffeine is an ergogenic aid, i .e. aids performance.

Jono (07:15.642)

But these people performed better, performed faster, and wildly everyone reported caffeine side effects, known caffeine side effects. And in that study, they had like a, I think it was four and a half milligrams and a nine milligram group of caffeine. So they had this dose response. And they told people you're in the four and a half milligram, you're in the nine milligram, piculogram group. And wildly, nobody got anything. But we almost saw like a dose dependent placebo effect.

which is pretty wild. And then my favorite, I don't know if that's the right way to put it, but I think the craziest one, there was someone in an antidepressant trial who took 29, what they believe to be antidepressants and felt that they were overdosing. I think they intentionally overdosed, which obviously I'm not gonna touch that, but they presented with, had hypotension, they really low blood pressure, they had to be placed on fluids and everything. And the thing that stopped those symptoms,

were when they were told, actually, no, you're in the placebo group. You just took 29 sugar pills and suddenly their symptoms subsided, which is wild. So why does this matter? I've probably already alluded to it, but the miraculous reports you're hearing about someone's new diet that they're following. Of course, now we've talked in other podcasts about how when you make certain changes to a diet, you often also make other healthy changes. I have talked about the carnivore diet before and people feeling better on it.

There's a whole host of other reasons that they might feel better on it. Increased protein, decreased processed foods, know, decreased calories, et cetera, et cetera, removal of food sensitivities. But it can also hugely be this belief that someone has when they go into that diet, that expectancy, because they have heard all of these other people raving about it. They believe it's going to work for them. So mentally they get these effects, right? Same thing with a supplement. If someone believes it's going to work for them, that placebo effect could be at play.

could have nothing to do with the supplement, which is why we need to be listening to these scientific studies. We need to be listening to the ones where there's a control arm and an intervention arm, or the arm is just group. We have these groups and we're done with all of the right protocols and things. And so I guess all of that is to say, I just want you to be aware of just how insanely high the impact from a placebo effect can be.

Jono (09:40.096)

And so if you are thinking, yeah, Jonah, I've heard this diet's dumb, but there's all these people that are saying good things about it. How can that be apart from people lie and survivorship bias, all these other issues. There's also this very strong placebo effect that as you can see, can make someone think they have overdosed on an antidepressant and give them physical symptoms. So in summary, stay critical, be extremely pessimistic. Worst case scenario, if you're really pessimistic about supplements,

You might be wrong, but you'll be right far more often than you're wrong. So it's still worth doing that. Anyway, thanks for listening. Like, rate, review, subscribe, share, tweet. Don't tweet, no one goes there anymore. But thanks for listening and I'll chat to you next time.