Dr. Melissa Ilardo
Appearances
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah. When you have two individuals who are closely related, that dramatically increases the chance that they're both carrying a variant that has a negative impact on the offspring. So, you know,
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
when you have people kind of mixing more outside their families, then it's very likely that even if you're carrying this deleterious variation, it's going to be kind of watered down by outside genetic material. But yeah, as soon as you have people too closely related to each other, you know, those things are ending up together and creating disease.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, so it's definitely nature has a system built in that says don't do that.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, absolutely. I think sometimes people kind of think we're done. We've reached this ultimate point of evolution. We've finished evolving. But as long as there are things that are affecting our ability to reproduce, we're going to continue to evolve. And especially once you have this introduction of new genetic variation.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I mean, some of the greatest adaptations in the history of humans have come from the introduction of new genetic material. So like the Tibetan high altitude adaptation is actually believed to have arisen from the crossing of humans with another early hominid group called Denisovans. So we essentially stole... the advantageous genes from this other group.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so maybe you'll start to see that happening again as you have a more globalized population where different groups of humans are creating these interesting phenotypes through the mixing of their genes that maybe will lead us to be more resilient as our planet is changing around us.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
You know, I'm going to get myself in trouble because I don't remember exactly how long ago it was. More than 10,000 years ago. More than 10,000 years ago. But it only became advantageous when the ancestral population of Tibetans moved into these extremely high altitudes. So they kind of, you know, it was just sitting there waiting for a chance to be really advantageous.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And then as soon as they went to these high altitudes, people carrying that genetic variation were at a huge advantage. And so they, you know, passed that along to their children and their children's children and so on.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
That's exactly right. So yeah, we see that happening with Neanderthals as well, but also this other population of, they call it archaic hominids, Denisovans. So these were a population that were found in areas of Asia, and their genes were introgressed, we say, so essentially inserted into the human genome.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So individuals from that region tend to have a higher ancestry coming from that hominid group.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yes.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Right, exactly.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Okay.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
That's right, yeah. And there's actually some extraordinary work from Svante Paabo, who works a lot with ancient DNA, where they found an individual who was a first-generation mix.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I think it might have been with Neanderthal, I forget now at this point, but it was a first-generation half-human, half-whatever archaea commonid it was, which shows you, I mean, if they found this, the chances that they would find this one, you know, mixed individual are so slim that it suggests that this was something that was actually happening a lot. for them to happen to find it.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, I mean, it definitely, you know, we have an ancestor. I don't remember exactly the name off the top of my head, but I have an issue with this diagram because it's, you know, it's the classic depiction of evolution. Right. But it really suggests kind of like I was saying before, this trajectory and we are the pinnacle of it. You know, we've achieved this thing.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And I think it also fits with this, you know, concept of survival of the fittest, which I think is, you know, also a little bit misleading in that, you know, it's not about the most fit. It's about the best fit. So evolution doesn't care how fit you are in the way we think of fitness. It only cares how you fit with your environment.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So, you know, the idea that evolution is driving any species, but especially ours, towards some optimum I think is inherently flawed.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
That's right.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, yeah. I mean, most mutations are deleterious. Most mutations cause problems. And so we actually don't even see most mutations because they kill essentially the offspring before it even becomes a fetus. So most mutations are happening in a way that we're not even seeing them.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So to wait for something that comes up that's actually beneficial can take forever because you have to have exactly the right thing. The genome's huge. So when those changes are happening, for it to not only happen in the right place, but to not cause problems takes a really long time.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So some of the faster examples that we know of evolution, especially in humans, come from when there's variation that's just already there. And, you know, it's not particularly advantageous, like I mentioned, with Tibetans until you move into a particular environment or until you start practicing a certain activity like breath hold diving. And so, you
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
You know, we have we call it standing variation. Just there's all these differences between all of us humans on Earth. And so when you have variation that's beneficial in the right environment, then evolution can happen a lot faster.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yes.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Thank you.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, absolutely. And I also love the X-Men, although if you ever want to ruin a perfectly good sci-fi movie, watch it with an evolutionary biologist. Noted. Yeah, so there are these incredible people, well, really all around the world, but I started my work in Indonesia called The Bajo. They are a group of what's called sea nomads.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So sea nomads are these people who spend their whole lives essentially at sea traditionally. They live on houseboats and everything they need they get from the sea. And they do this through fishing, of course, and other things like that, but also through an incredible amount of breath hold diving. So they're extremely good at this. They can hold their breath for many minutes at a time.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
They dive to incredible depths. A lot of them wear these jewelry made of black coral. Black coral only starts growing at about 100 feet deep, so that tells you how deep they're diving.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
They're actually meant to protect them from evil spirits and things like that.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah. So I was told, and I always emphasize that, I was told I did not see this. I did not record it. I was told 13 minutes. And this was by the father of a diver who I worked with in Indonesia.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It is. Yeah. I'm trying to remember what the current world record is, but it's also, I mean, you have to think about if you see them diving, like it's incredibly active. So a lot of the breath hold records that we think of are people floating in a pool. They're not moving. They're not expending any energy. They're not using up that oxygen as quickly.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And these sea nomads are, when they're underwater, they look like hunters on land. They go deep enough that they're not floating anymore. And so they're walking on the surface of, you know, the bottom of the ocean with their spear guns and they look like hunters. It's incredible to see.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It's very impressive. Yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
They do, yeah. And in fact, they spend so much time traditionally on these houseboats and so little time on land that a lot of the children actually learn to swim before they learn how to walk. So one of the divers, when I was out there, one of my colleagues noticed that one of the diver's feet was very soft. And we realized that it's because he's never really walking.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
He's just always in the water. So his feet don't develop the same kind of calluses that ours do because he's not using them like we do.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, so I was actually diving as part of a coral genomics project in Thailand, escaping Danish winter, because that's where I was doing my PhD. And I heard about a population called the Moken. So that's another group of these sea nomads.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And heard about their incredible underwater diving, started looking into it, and saw a study that I think you've seen that showed that children, Moken children, could actually see underwater better than European children. And started thinking about, you know, I mean, freediving is really dangerous.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so I was thinking that this could actually be something that's driving selection in this population that's causing this population to evolve.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, exactly.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Exactly.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Exactly. Yeah. Yeah. And, you know, I mean, we see with competitive breath hold divers, you know, I've never actually been to one of these competitions, but I've read about them. People pass out underwater all the time and they're, you know, pulled to the surface and revived.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
But if you're a sea nomad diving in the middle of the ocean with no one nearby, nobody's going to pull you out of that water. And so you've just removed yourself from the gene pool completely, whereas someone who maybe has a variation or has genetic variation that's making them safer at diving might survive that.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yes.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah. So this is exactly what gets people in trouble because, yeah, like, you know, we don't have a reliable sensor for when our oxygen is low. And so that happens to people underwater because that feeling, that wanting to breathe is a buildup of carbon dioxide. And so, yeah, people teach themselves to overcome it, like they're suggesting you do there.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And then, you know, you're underwater and you pass out and that's it.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Right.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Exactly. Yeah. Yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Right, yeah. There's so much cultural knowledge that's integrated into the practice and that's passed on from generation to generation because a lot of times they're doing this in family units. One of the divers that I worked with, his dad used to be the most famous diver in the village. Now he's the most famous diver in the village.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I think that's something we're still understanding at this point. I mean, I think every day we're getting more and more information about the ways that we can actually modify gene expression and these things that we thought were totally predetermined in the past. And so I think we're still learning with epigenetics and all of these new fields just how much we can actually change things.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so there's a lot of that tradition and that traditional knowledge that's passed on despite it maybe not looking like what we would read in a textbook.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
You know, it would be interesting to count that. I think now, you know, things are changing for the Baja, at least the community that I worked with, where a lot of people are moving away from traditional diving and into other kinds of fishing practices.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so I think at this point, you know, this prowess, this respect for these, you know, these divers is more respect for the fact that they're keeping the tradition alive and they're continuing this tradition, even though it's a very hard thing to do. Um, but yeah, it would be really interesting.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I know actually the one, the one diver came from a very big family and that was something that the Bajo actually asked me about was why, why did the Bajo have so many children? And so it would be interesting to see if, yeah, diving success correlates with reproductive success. Cause you could imagine that it would, I mean, they're, they're diving for things that they're eating.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So why wouldn't that, um, increase your success on that?
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
They dive for, it depends on where they are. They're spearing a lot of fish. Everything is delicious. They dive for shellfish. They also harvest seaweed sometimes. And they actually collect a lot of sea cucumbers, which they dry out in the sun and then eat later.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, so we started thinking about, okay, you know, for natural selection to act in this population, it needs some kind of physical trait to act on, which got us looking at the dive reflex or the mammalian dive reflex.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So this is if anyone, and again, I hesitate to tell people to do this, but if you hold your breath and put your face in a bowl full of cold water, your body responds as if you're diving. And what that means is that your heart rate slows down.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Your blood vessels and your extremities constrict because, you know, your fingers will be okay with a little bit less oxygen, but your brain really needs that oxygen. So it's keeping the blood central where you need it the most. And then your spleen contracts. And so the spleen certainly wasn't the first organ that I thought about when thinking about diving. But the spleen is a reservoir.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
There are, of course, things that are kind of written in our genes, but I think we're learning that there's a lot more that we can change.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I mean, the spleen does many things, but one of the things that it does is it's a reservoir for red blood cells that are carrying oxygen. And so through that contraction, those oxygen-rich red blood cells are now pushed into circulation and you get an oxygen boost.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It's about 10% in most of us.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Exactly. Yeah. Yeah. I mean, it's enough to make a difference.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, that's right.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, usually in like lab protocols, we do it at about 10 degrees Celsius or 50 degrees Fahrenheit, so quite a bit colder. For how long? Well, depends on how long you can hold your breath.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, so the extent to which like how long the contraction actually takes, I think we have room to learn more about that. But one thing that's slightly different from what you're talking about is that after you stop holding your breath, your spleen takes – that oxygen back essentially. So it refills with red blood cells and that oxygen is no, that extra boost is no longer in circulation.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
That's right. Only when you need it the most.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Well, you can live without one. So it seems like how important could it be?
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Exactly.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It's involved in the immune response to certain bacteria. And actually, I'm trying to think of what else it does, but that's the main role is immunological. Mm-hmm.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, as far as I know, it's all unconscious. It's not something that they talk about. And, you know, most of them, you know, when I was explaining what the spleen was, it wasn't something that they had ever thought about or, you know, experienced any kind of sensation in the area where the spleen is found. Yeah, but who knows?
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I mean, it's encapsulated in smooth muscle, I think, the spleen, and that's what controls that contraction. So... Yeah, maybe there could be some way to consciously contract your spleen. We also, our spleens contract when we exercise to a lesser extent.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And this is why like horses and apparently greyhounds, someone wrote to me after the study came out, have massive spleens, as do seals who do a lot of deep diving. But that makes a little more sense.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, it could be that. Yeah, it's something in the kind of breath holding aspect of extreme bouts of exercise is also contributing to that contraction.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, there's – it's stimulation of the vagal nerve that is in part triggering this response, which, you know, runs through your face. And so that's why the, you know, the facial immersion is crucial to triggering the response. But there is, I think, a component of if you're just holding your breath where that also kind of triggers it. So –
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Um, but yeah, it's really amazing to think that as mammals, this evolved sometime so long ago that it's in, it's even in mice. They've done a study where they actually trained mice to dive and they could measure the mammalian dive reflex in mice.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, I mean, it's a great question. I don't think we really know. There's a – some people talk about something called the aquatic ape hypothesis that says that one of our ancestors – Sorry, I'm trying not to interrupt, but I just – someone – I've heard of the stoned ape hypothesis. Okay.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Forgive me for interrupting.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
The aquatic ape was right there alongside the stoned ape. But I think that, you know, given the fact that it's present throughout all mammals, I think it's much more likely that it was some very long ago ancestral, you know, proto-mammal that was doing some kind of diving. And because of that, this response is present to varying degrees in all modern mammals. Yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I mean, it seems like it. I mean, I've seen, you know, if you take babies and not recommending anyone do this, but like blow in their face, you know, they instinctively hold their breath and can be put underwater. And actually, Bajo, people told me, and I don't know if this is something they actually do, but that the test of a Bajo... is as a baby, they pass the baby under the canoe.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And if the baby comes out the other side, then it's a Bajo because it has held its breath like it will for the rest of its life. What's the alternative? Yeah. That's why I said, I don't know if they actually do this, but it was just something that they told me. But yeah, I think there is some innate response where we know even as babies to hold our breath.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So we discovered that they have larger spleens. So, you know, I mentioned the spleen's role in diving. It's increasing your, sometimes people call it a biological scuba tank. You know, it's increasing the amount of oxygen available to you. So, you know, our hypothesis was that they would have larger spleens because a larger spleen presumably means longer diving, safer diving.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so we compared them to a nearby population living in a very similar environment, but with a history of farming. So these are people who live right next to the ocean, but aren't really interacting with it. So, you know, Bajo children are in the water from the moment they're born almost. And then children in this other village didn't know how to swim.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so we found that compared to that village, the Bajo had significantly larger spleens. So their spleens were about 50% larger on average. And this was true for divers and non-divers. So that showed us that it was very likely to be something genetic rather than the fact that your diving increases the size of your spleen.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
This is a question that I think is still open because in both of the populations where I've measured this, divers and non-divers have the same size spleen. However... Other people have shown that, you know, when you train, if you train people, if you recruit people to a study and train them in breath hold diving, their spleens increase in size.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So I don't know if it's just that the populations that I've worked with have some kind of genetic factors that override that change. But yeah, open question, I would say.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
The gene that we found that was evolving in the population correlates with higher than average thyroid hormone levels. So not like clinically hyperthyroid, but higher than average. And this is actually also true for Europeans who are carrying the same genetic variant. We showed in another group of individuals that if you have this gene variant,
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
you have higher thyroid hormone levels and you have a larger spleen. So it's not just something that's true in the C-nomads.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so what we think is going on potentially, and this relates to the work that we did with mice as well, is that because of these higher, I hesitate to say elevated because that's a clinical term, higher than average thyroid hormone levels, the mice, the humans, whoever it is, are producing more red blood cells.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so now whether that's kind of stretching the spleen, you know, because the spleens that we saw in the mice were larger but less dense, or, you know, if there's some other mechanism, we're not completely sure yet.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
But yeah, it seems like these higher than average thyroid hormone levels, at least when the genetic cause was what we saw in the C-nomads, increased the size of the spleen, increased hemoglobin, increased hematocrit, increased red blood cell count.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah. Yeah, and I don't think know how quickly the spleen reuptakes those red blood cells, but it does do that eventually. So maybe this is something that would be advantageous for short bursts or something like that.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I mean, I think there's a lot that we don't know about the performance-enhancing aspect of this, but that's really interesting because the work that we did in the mice where we replicated what we saw in these divers –
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
They had larger spleens, they had higher red blood cell count, but they did not have any change in erythropoietin, which is how we normally think about changes in red blood cell count. This is a drug that was really popular with cyclists for a while. People would self-dose with erythropoietin and it would increase their red blood cell count dramatically to improve their performance.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So this is like an erythropoietin independent mechanism of increasing your red blood cell count that could have an advantage in performance, I think.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, absolutely.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Oh, absolutely.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I haven't seen any studies that look at that, but it would be really interesting because, yeah, I mean, like you, I also would do anything to not get sick. And we do see in these populations a lot of older people who are continuing to dive. And there is a seeming health and robustness that I wonder if it's related to the activity of diving itself.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, just going back to eye color, because this is just one of my favorite genetics facts. So everyone with blue eyes descends from the same person. So at one point in human history, one person had a change in their eye color. And it's just like amazing to imagine this person who had blue eyes for the first time.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Swimming a mile is, yeah, that's quite impressive.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I would imagine.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, I mean, it's so low impact and such a natural way to, you know, to move, to exercise that, yeah, I think especially as we age, it would be a really wonderful way to stay fit and healthy.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
That's a really good question. We haven't looked at that, but it would be really interesting to see because, I mean, you know, the oceans are an incredible resource in terms of food availability, especially to early humans. So you would imagine that anyone living near a coast anywhere would take advantage of this resource.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So it would be interesting to see if maybe coastal populations are more likely to carry the genetic variation that enables this behavior. Although there are actually skeletons that have been found in various parts of the world near river systems that also suggest that those people have been diving. So maybe it's just being near water anywhere in the world.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It seems to be that way, yeah, all over the world.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah. So, you know, speaking of older divers, there's a group in Korea on an island called Jeju. These are all female divers. They're called the henyo, which just means sea women. And the average age of the henyo currently is around 70 years old. So that's when I think of robustness with age, I think of the henyo.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
But this all-female diving population has likely been diving in that region for thousands of years. And what's really extraordinary about the Henyo, there's a few things. First of all, they're diving in extremely cold water, especially compared to the Bajo in Indonesia.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
No wetsuits. Well, now they wear wetsuits. Up until the 80s, they were diving in these cotton bodysuits that you can see provide zero thermal protection. I mean, it's just cotton swimsuit, essentially. So, you know, diving with no protection in extremely cold water. And as women, they're diving throughout pregnancy. So they're diving up until the day they give birth sometimes.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And then through many generations, probably because that was a very attractive and interesting feature in that individual, you know, that spread throughout human populations as we know them. So I always just find that to be fun about blue eyes.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And then they're back in the water a few days later. So this has really shaped this population in really interesting ways.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
This is a really good question I get asked a lot. How deep do any of these populations dive? And there's just, like, not really data. So we don't really know. You know, now we're starting to see, you know, we're looking at the Henyo. We actually tracked some of their diving. And their dives tended to be much shallower, you know, not really going any deeper than 10 meters, 30 feet.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
But they're also in their 70s, 80s even. You know, we had an 81-year-old diver in our study.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
We had a 20...
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, exactly.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, yeah, and I shouldn't say it like that. It's just that compared to, you know, the Bajo have been documented to dive deeper than 200 feet deep. Oh, I'm not countering.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It's very impressive, yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Right. I mean, again, there's no documentation of how these women have been diving throughout their pregnancy other than we know that they were diving throughout their pregnancy. But yeah, presumably in their youth, they were diving to these depths with their unborn child inside them. So it's a really – I mean, when we think about natural selection and evolution, something that's able to act on –
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
pregnant woman has the opportunity to take out two generations if there's not genetic variation there that's protective. So it's like if we want to talk about really fast examples of evolution, it's anything that's acting on pregnancy. And that's what we think has been happening in this population.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
We don't totally know. I have my own personal theory, which actually relates to the fact that in a lot of places with cold water, so in Korea, in Patagonia, in Aboriginal Tasmania, it's all women diving. So I suspect that there's something unique about the physiology of women. um, that makes us better at diving in cold temperatures.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Interesting.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It could be. These are some tough ladies, I will tell you that, even into old age. My colleague, Ju Young Lee at Seoul National University, she's been working with them for a very long time. And she did a study where she was trying to find retired haenyeo. And the only ones she could find were over 100 years old. Because they basically don't retire. They just die until they die, essentially.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So she had these two women who were about three feet tall who were retired henyo because those are the only ones she could find.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Mm-hmm.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
No, no. And I mean, it would certainly be interesting to explore, but I don't think there's any evidence so far other than anecdotal. I would love to do that study. Yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Right.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I think that's right. Yeah, I think it's the most rare.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Right. Exactly. Yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
70s, 80s, beyond, I guess. The oldest diver that I've personally worked with was over 80. But, yeah, they're so athletic as they do it. But, yeah, in terms of are they revered, I think now, yes. I think that wasn't always true. One haenyeo told me that in her youth she was kind of embarrassed to be a haenyeo.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And a lot of it's because, you know, they're exposed to the sun, so they have darker skin than a lot of other women. They tend to be very loud because a lot of times they rupture their eardrums from diving. If they don't pressurize correctly, they can have hearing damage. So they're known for being very loud.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so I think there was kind of a marginalization early on, but now they're recognized as a UNESCO World Heritage intangible site, essentially. And there's just, I think, tremendous respect for the population now.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
They are diving for all kinds of things. They're diving for sea urchin, abalone. They also harvest seaweed. Um, I've seen them pull up octopus, uh, they'll spear an octopus, um, and they, and they do it in a very interesting kind of controlled way. Like they're really guardians of their marine environment, um, where they don't, they make sure that they don't overfish things.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So the sea urchin season is very short because, you know, if they over harvest the sea urchin, that population won't replenish. So they have this, you know, system where they, they really take care of the marine environment.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, I think in the history of humans as a species, I think that was our original eye color. And so then, yeah, having these other eye colors arise in the population created these events. I think green eyes, if I'm not mistaken, there were multiple people, you know, that comes from different genes from different individuals in the history of humans.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah. I'm still developing a taste for me. I'm trying, but when it's, when it's fresh out of the shell, there's nothing better.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Right, right.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, yeah. And in these cold temperatures as well.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I mean, it certainly could. Diet is an incredible driver of selection. So, you know, a very common example of natural selection is lactase persistence. So our ability to continue to consume milk past infancy. And that happened very quickly in multiple different human populations. So it happened in Africa and it happened in Europe. And another example is the Greenlandic Inuit.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
A huge part of their diet was marine mammals that have really high lipid content. And so they actually evolved to be able to better metabolize those lipids so that it wouldn't, you know, kill them from heart disease or something like that. So yeah, diet as a driver of selection is extremely strong. So it may be that this has been shaping our species in ways that we don't even know.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, so we found two different adaptations. And I say adaptation, but there's kind of adaptation in a physiological sense, this thing that you can do by training, or adaptation in a genetic sense. And we have found one of each. So the training adaptation that we found was that I mentioned before that when you dive, your heart rate slows down to try to conserve oxygen.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So their heart rate through a lifetime of training slows down even more. So we could actually – you could visually see this when they were doing these dives – Watching their heart rate, you could just see it plummeting. We had one individual whose heart rate dropped more than 40 beats per minute in less than 15 seconds. Yikes. So really dramatic.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
But yeah, blue eyes is just this one individual.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And the reason that we think that that's a training adaptation rather than a genetic adaptation was that it was only true in the divers. So non-divers with the same genetics... didn't have this phenomenon. So that was, I mean, that has, you know, it's interesting to think about how, what the potential health benefits of that could be. I mean, it's clearly something that you can train.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
This has also been observed in other competitive breath hold divers. But in terms of how that could benefit your health, I mean, maybe it's good for your heart to have that kind of plasticity in terms of its response.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Right, yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah. And so then we also found this genetic adaptation that we think is driven by the fact that they're diving through pregnancy. So when pregnant women have sleep apnea, which is where you hold your breath in your sleep, so it's kind of you can think of it as unintentional diving through pregnancy. they tend to develop these blood pressure related complications.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So like preeclampsia, they call them hypertensive disorders of pregnancy. And so we think that, there's no studies that have shown this yet, but we think that if you're diving, different kind of apnea through pregnancy, that would also increase your risk for these disorders.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so what we saw was that there was a genetic variant that was actually driving their, like a lowering of their diastolic blood pressure while they were diving. And so we think that this is protective against these hypertensive or high blood pressure effects.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Interesting.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It is, yeah. I think we think of it as just snoring, right?
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah. You're putting yourself into a state of hypoxemia, so your oxygen is very low.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, I mean, I think, well, that's one of the things that we're hoping to find from studying these women. So if they've evolved some kind of protective mechanism that protects them in the case of apnea, maybe that's something we could develop into a therapeutic that could be used to help prevent that same hypertensive disorder pregnancy in pregnant women who have apnea for other reasons.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
But otherwise, I would say I think preeclampsia used to be a death sentence for mothers and fetus, which is why it was such a strong driver of evolution. Now I think awareness of it enables treatment, but that's only something that's happened in the last I don't know how many decades. So that's why it could have been such a powerful force in this population.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
That's really interesting.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah. I mean, you know, I'm not a maternal health specialist, but I do know that most mutations create non-viable embryos. And so, yeah, that's, I think that could certainly be driving the early miscarriages, especially.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, because, I mean, a lot of proteins are involved in many, many systems. And so if you have a mutation that's problematic in one of those proteins that's involved in all these different systems, it's just going to start to go haywire very early on.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, absolutely. Yeah. And I mean, you know, to your point, like the phosphodiesterase that we found that was evolving in the Bajo, phosphodiesterases are involved in so many different functions. And so there's, you know, there are chances for these mutations to affect not just the systems that we're interested in, but other systems as well.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I mean, in both populations, the people look incredibly fit and athletic, and they tend to have just a very robust appearance. Now, is that because they're diving every day, and there aren't that many 70-year-old women who are jumping off a boat every day to go to work? Or is it something related to their genetics?
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I don't think we know yet, but it would be really interesting to look into that more.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Right.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I think that certainly, you know, I mean, we know that these populations have been evolving. We have theories as to what is driving that selection, but they're, I mean, could be sexual selection.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It could be, like you're saying, like that people carrying this genetic variation that happens to also make them a good diver in ways that we expected to find, also make them more attractive in ways that we weren't even looking for. And, you know, we weren't even thinking about pregnancy really when we started the study with the Henyo.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It wasn't until we got these results and we're saying, you know, what is this difference in blood pressure? And speaking with maternal health specialists that we really pieced it together. So I think it's the kind of thing where, yeah, you just you don't even really know necessarily all of the pieces of the puzzle. And that's where it's a lot more questions for us to ask in the future.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So now they do. Okay. But, I mean, you can imagine goggles haven't been around that long. So at some point in the past, they didn't. And this was, you know, the study that first got me interested in this was a study done in Moken Children, where I think it was literally a researcher who was on vacation in Thailand studying
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
noticed these little kids diving for things and, you know, having this ability to see underwater and set up an experiment and had European children and Moken children diving to look at things underwater. And the Moken children had better eyesight underwater than the European children.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Now, that same researcher, after publishing this paper, went back to Europe and trained European children to do the same thing, essentially, to perform at the same level as these Moken children. And so, you know, there was this kind of dismissal, like, oh, well, you can train Europeans to see underwater just as well, so it must not be evolved. It must not be genetic. It has to just be training.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
But I think that's a logical fallacy that has stopped – a lot of, or has prevented a lot of research from being done in these populations because just because you can train someone to be at the same level, you know, as someone else doesn't mean that that person didn't have an advantage.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Um, and so I think that's, uh, yeah, I mean, there definitely, there's a difference in their vision and what causes that. I think we still don't know.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Elliot Kipchoge.
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Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
You know, I would love to look at that scientifically. He's absolutely incredible. I mean, breaking the two-hour marathon record is also just unbelievable. But I think there have been, you know, I'm not as familiar with this literature, but there have been studies looking at the proportion of like bone lengths in certain parts of Africa, especially.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It's also interesting to note that a lot of these really talented runners come from Ethiopia, where there are highland runners. areas where humans have actually adapted to altitude. So in addition to some of these like biomechanical advantages, they may actually also have physiological advantages that enable them to run faster.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
But yeah, I think this is an excellent example of there's clearly something biological making people from this part of the world you know, really excellent runners. And just because you can train a European runner to compete at nearly the same level, that doesn't mean that there's not something special about people like Kipchoge. And so, you know, this comes up a lot with the Bajo as well.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
People say, oh, well, you know, they don't hold the free diving depth record. It's like, well, yeah, but they're not training to hold that record. You know, they're training, they're diving just to collect food for their families. They're not training. So what would happen if we did train them? And I think it's a great point.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, I mean, I think certainly, you know, I mean, there's an interesting correlation between people in STEM fields and having family members with autism. And so I was actually at a lecture in Princeton where the professor – asked the incoming class of students, you know, how many of you have a family member with autism?
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And then of those, you know, he displayed the statistics, how many of you are joining the engineering department? And it was, you know, it was much higher amongst the engineers. And he explained that this can have to do with the fact that, I mean, people on the spectrum tend to have an ability to hyper focus.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And that actually makes you, you know, the ability to really kind of narrow yourself to this one thing can make you a really good engineer. And so in that way, it's, you know, it's a huge advantage because it's allowing you to succeed in that field, you know, depending obviously where you are on that spectrum and how that affects you in other ways.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so if that in some way is giving you an advantage, you know, why wouldn't it be selected for? Of course, there are other ways that it could be a disadvantage. Oliver Sacks, I think, wrote about how people with Tourette's may have faster processing speeds.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so, again, maybe this is a place where, you know, that is advantageous, despite the other disadvantages that might come along with having that syndrome.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Oh, did he? I didn't know that.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
The disorder. Yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It's interesting because it becomes a really difficult thing to test because how do you measure creativity in a way that you could then link to genetic information?
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So a lot of these kinds of understandings of genes come from things called genome-wide association studies, where essentially they perform a correlation at every site in the genome to see which of these sites correlate statistically with whatever phenotype it is. So whether that's, you know, kidney disease or, you know, creativity. But you have to have a really good way of quantifying that trait.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So, you know, creativity is nearly impossible to quantify. Something like mathematical ability, there's so many potential environmental nurture factors that could contribute to how that manifests in an individual that it also becomes quite difficult to quantify and therefore difficult to find any genetic factor that's contributing.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I mean, you know, there's like companies where you can test yourself to find out what kind of athlete you should be. And I think that kind of gets into something called genetic determinism, which is this idea that your genes determine everything about you. which we know isn't true. We know that it's a combination of genetic factors, environmental factors, all of these different things.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
But I think it's interesting how much the idea that we're genetically predisposed to something or we're genetically better at something can actually influence how we are at that thing. So we talked a little bit before about
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
You know, there was a study where they told people, they said, we're going to take your DNA, we're going to genotype you, we're going to find out, you know, whether if you train, you're going to get faster or whether it's not going to affect you at all. And so they did that and they put people into these groups and then they tested them after a few months.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And the people who they told were going to do better did better. And this was like something they can measure at the biological level. They could measure DNA. specific molecules that had changed in that population of people compared to the other group of people. Now, the trick was that there was no difference genetically between these groups. It was just what they were told.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So it's really interesting to think about, you know, if you tell a child what they should or shouldn't do based on, you know, their genes, I think that's a really dangerous thing. Or potentially you could motivate them through that.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
We really have very little evidence that intelligence is heritable. So I think that's a big one, especially if you feel like you're not coming from a very intelligent family. That doesn't mean anything, really, based on what we know currently.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Oh, man. I don't know, but I'll tell you, I did not inherit any rhythm from my dad.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, I mean, it's a really great question. And I think one without a very good answer at this point. I think one of the things holding back this discussion up till now is that CRISPR is still a little bit of a blunt tool. You know, we're not, we haven't, like the way that we're applying it
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
isn't as precise as we'd like it to be to do the kind of gene editing that, you know, you would need to protect babies in the way that you're describing. And there are things like off-target effects, they say. So, you know, you're trying to edit one very specific part of the genome, but it ends up editing places that you didn't intend it to edit.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So that's kind of one of the issues, I think, technologically. I think if I remember right when that happened, people were a little bit like, that technology isn't ready to be used in that way yet. But, of course, that's something that is changing really rapidly. We're getting so much better at this. We're able to do it successfully in lab animals. And so, yeah, ethically, I mean, it's just –
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I think it's also interesting to think about, you know, enhancement versus, you know, like correction. Like at what point, you know, where is the line between those two? So if we're correcting some kind of genetic defect, first of all, some defects, other people might not even see them as defects. They might just see that as variation amongst humans.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
So, you know, where is the line between defect, normal, enhanced? And so it's, yeah, it's, I don't know who would make those decisions, right? once the technology is even available to apply that in unborn children. I mean, of course, it would be a dream to prevent disease using these technologies, but it's a slippery slope maybe.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, depending on the coverage. Yeah, you can sequence a genome for pretty cheap these days.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah. Well, first of all, for context, I only have dogs, so I don't have to think about this in terms of human babies. But yeah, I think... say you get your baby's genome sequenced and that baby is going to be blind. Is that a problem? You know, a lot of blind people would say no. So, you know, I think it's such a personal question.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yes.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, my fur babies were 100% selected to be cute.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It was the eye contact? Yeah. I mean, actually, literally, one of my dogs is a type of dog that was bred to be a companion. So the only thing that they selected for was cuteness and companionship. This is the Bolognese? Yes, that's right. Yeah.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, named after Bologna in Italy. Oh, right.
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Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Bolognese.
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Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
It's in the family of like the Maltese, Bichon, Cotone family. So these little fluffy white dogs that are in Renaissance paintings sitting in the laps of royalty.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, so starting with admixture. Admixture is just when different ancestry populations mix. So it's kind of this relative term because if we're all descended from one ancestral population, then maybe we all have one ancestry. But I always like to put it in the context of myself. So my dad is 100% Italian. My mom's a mix of Northern European.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I am an admixed individual, you know, if you think about it that way. And the reason that this is important in genetic studies is that if I claimed to be Italian and were included in a genetic study of Italians, the genetic variation that I have coming in from my mom's side would confuse that analysis. So admixture creates a ton of problems when we try to do genetic analyses.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so that's generally why we try to quantify it in genetics. But yeah, you know, when we're talking about, it depends on kind of what scale, because I'm 100% European. So in that way, I'm not admixed, if we're talking on the scale of continents. So it becomes kind of a blurry concept of admixture. depending on what level we're looking at.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
But as to your question of whether we are all one species, I would say I've actually, this is not the first time I've been asked this, especially given these, we call them superhuman populations, these people who have these extraordinary abilities, extraordinary physiology that makes them really good at what they do.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
I think the thing to keep in mind is that some of that variation can come from just a single base pair difference. I mean, a lot of times it's multiple genetic changes that create the differences between individuals. But when you think about eye color, that's just one genetic variant in some cases, like the case of blue eyes. So you could be exactly the same as someone else
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, so I mean our genes are constantly changing how they're expressing based on what environmental stimulus is coming in. So we have these changes that happen on the order of minutes or hours or things like that. Then there's also changes that we're finding out are happening kind of over generations. So we now know that there can be epigenetic changes. So these are changes –
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
except for this one change out of 3.5 billion. You know, so does that, like, at what point do we need enough genetic diversity to call a group of humans a different species? And I don't think that's something that we see anywhere on the planet that I know of.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Thank you so much for having me, and you're welcome in the field anytime.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
you know, little modifications to the genome that happen by things actually, molecules actually attaching to the genome and changing how genes express, that can be passed down. So this is really interesting from the perspective of things like trauma.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
You know, we know that, you know, refugee populations actually have some of these changes that they've inherited from their parents, even if they weren't, you know, victims of the event that caused them to be refugees.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, it's a very good question. You know, in the case of trauma and refugees, I'm not sure. I do know in terms of starvation, that's been something that's been studied as well. So there was a famine that affected Dutch people several hundred years ago, I think. And that was actually also kind of recorded in these epigenetic changes.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so presumably that's a change that is helping that population to better survive. So in that way, it's resilient. But then, you know, you think about in a contemporary situation where, you know, food is abundant, maybe that is no longer beneficial, even though at one point it was.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And so then we have this other kind of order of change, which is, you know, actual changes in the genes themselves that either arise from mutations in, you know, these single base pairs or at many different sites or things like variation that's already present in the population at a certain amount. that then increases in frequency throughout the population.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And this is where a lot of my work has focused. And these are changes that, until recently, we thought would take 5,000 years, 10,000 years at least. And now we're starting to understand that maybe that can happen in as short as 1,000 years, 2,000 years.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
They did a very similar study in humans, and humans also are drawn to other humans that have these differences. So it's interesting, especially with the immune system. There was a study where I think they had people smell sweaty T-shirts of members of the opposite sex if they were heterosexual to see how attracted they felt to the person just based on the smell of their sweaty T-shirt.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And people were more drawn to people who had very different immune systems than their own. So I think this is something, you know, we see it in mice and it's easy to say, oh, you know, it's their animals. Of course they do that, but we do it as humans too. And it'd be interesting to know to what extent that's influencing our choice of mates and spouses.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And specifically the immune system that you're talking about, you know, the – What is it? Histocompatibility? Major histocompatibility complex. Yeah. The more different they were in that, the more attracted they were to that smell.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, I mean, I think it could be. It's also interesting, you know, we have, you know, when you're talking about hybrid compatibility or hybrid.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
Yeah, something like that. You know, we're having with globalization, people meeting each other, you know, across cultures, across continents. For the first time, so we're getting genetic combinations that have never been possible in the history of humans.
Huberman Lab
Behaviors That Alter Your Genes to Improve Your Health & Performance | Dr. Melissa Ilardo
And that's creating some interesting both kind of resilience and then also disease because you have combinations of genetic variants that have never been in the same individual before that are now showing up together.