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Myth-Busting Wellness Hacks: Cold Plunges, Coffee, Alcohol, and Fitness Trackers

Brad Stulberg and Steve Magness join to talk the science behind the hype-filled world of biomarkers, biohacks, and fitness

Fitbit And PH5 Host Harley Pasternak Workout Photo by Rich Fury/Getty Images for Fitbit

Today, we go wading in the murky waters of 2023 wellness trends. We’re talking cold plunges, fitness trackers, and recovery scores. And on the more prosaic side, the real science of coffee and alcohol.

Today’s guests are Brad Stulberg and Steve Magness. They are the cofounders of The Growth Equation, a multimedia platform dedicated to health, excellence, and well-being. They are authors of Peak Performance, Do Hard Things, and The Practice of Groundedness. And for quite a while I have considered them to be ideal guides in this hype-filled world of biomarkers, biohacks, and fitness.

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In the following excerpt, Steve Magness talks about the potential benefits of cold plunges and the wellness culture that promotes them.

Derek Thompson: So for whatever reason, wellness hacks are always in season. But it does seem to me, just as a casual consumer of Twitter, Instagram, TikTok, that we do seem to be reaching a new peak in bro wellness influencer. And I wanted to bring you guys on because you are very good at looking comprehensively at this space. You are careful, you are anti-hype, you are pro-science with a small s, which I would define as believing in the process of science. You believe in the findings of science, but you also believe in the nature of uncertainty. And the fact that just because there is a study that comes to a conclusion does not mean that whatever nutritional or behavioral intervention that was discussed in that study thus has to become the new law that we have to govern our wellness mornings by.

So I wanted to have you guys on to educate me on some of the tips that I see flying around the internet. The first one is cold plunges. Steve, why don’t you get us rolling here. I see a lot of people on the internet, ordinary people, submerging themselves in ice baths saying that this is the morning intervention that is going to change everybody’s life. In my corner of the world, cold plunges and morning cold exposures have been repopularized by, among other people, Andrew Huberman of the Huberman Lab podcast. They’ve totally taken off on social media. What does the science tell us about cold plunges?

Steve Magness: Yeah, this is one of those things where I’m not sure it would take off unless we had Instagram to post it to everybody, but I think the science is pretty clear. And there’s a couple things that I want to get at here. First, there’s things that actually occur, like the hormonal response. So if we think of jumping into an ice bath or cold plunge or what have you, you get this surge of hormones and neurochemicals, so adrenaline, dopamine, beta-endorphins, all sorts of good stuff. And there’s a feeling attached to that.

We feel more energized. And I think what is interesting here is that we get lost in what I call “biomarker madness,” which is when we point to the hormones and say, “Man, that gave me a 500 percent increase in adrenaline or a 200 percent increase in dopamine according to the study, so it must do something.” But I think we lose context around here because if I went for a walk, if I literally went for a 15-minute easy cycling ride down through the neighborhood, I’d get a several hundred percent increase in adrenaline. If I did a hard workout, if I went to the track and did some intervals, I would probably get somewhere around a 10- to 15-time increase in adrenaline. Same goes with dopamine, to a similar extent.

So I think here the key is not to get lost in the hormones, but to get to the functional results, what actually is changing. And there, I think if we look at the science, especially on psychology and mood, it’s a little bit more nuanced in the sense that, yes, it shows that in the short term you get some changes in mood and elevation. And a lot of the studies actually show that it’s more a decrease in negative affect or negative mood than an increase in positive because essentially the shock, the stress response, distracts you or takes you away from anything bad you were thinking about because you just jumped in a freezing-cold plunge.

So I think on that, it’s the short term. So what I would say is if it makes you feel better, go for it. Is that causing any sort of long-term change? Most of the research, especially when you look at long-term mood, depression, things like that, is that (a), there’s not much research. And then (b), most of it shows that in terms of jumping in cold water, it’s more swimming in cold water than just sitting in cold water. And then the other key component here that is talked about a lot is the metabolic aspect, which is “Hey, does this help you lose fat? Does this help you burn calories?” And again, I think [with] the science, we need to almost take a step back and separate hype from reality. And the reality is that, yes, jumping in cold water increases caloric burn a little bit, mainly through shivering or trying to heat your body because it’s really freaking cold.

But the effect of that is, unless you’re sitting in there for an hour, the effect is a handful of calories. Most research says a 15, 20 calorie burn difference from shivering and sitting there after the ice bath. And the other thing on this that I think we have to separate [from] the hype is a lot of times other podcasters or researchers will bring up this idea that cold activates this thing called brown fat, which brown fat is pretty simple. It’s more metabolically active fat. So babies have a lot of brown fat. So it means it burns more calories, right?

Adults tend to have a very small amount of brown fat. So much so that activating it will tend to burn, again, an additional maybe 10 to 20 calories over a day based on most research. And if you look at, OK, cold water activates brown fat, but does that cause any sort of functional change? I would say the research at this point points us to it’s a nice bio-plausible theory, but in terms of functional results, there’s not much there yet. So it is not accurate to say, “Go freeze yourself in an ice bath, and this will help you with weight loss,” because the data just isn’t there. And it’s not that plausible either, I would say.

This excerpt was edited for clarity. Listen to the rest of the episode here and follow the Plain English feed on Spotify.

Host: Derek Thompson
Guests: Brad Stulberg and Steve Magness
Producer: Devon Manze

Subscribe: Spotify