Rhonda: Have you seen that before where you can see people have, for example, like other clinical biomarkers that are unhealthy like higher fasting blood glucose or maybe elevated triglycerides, elevated C-reactive protein, a marker of inflammation? Do you find that those typically correlate well with the epigenetic age or...?

Steve: I wouldn't say it correlates well. It correlates, you know, so people who have high levels of inflammation and what you mentioned, the epigenetic clock goes a little bit faster, but the word is there's a weak relationship, you know, because it is quite possible that somebody turns out to be in good shape according to epigenetic aging rates. And the number one example I want to mention in this context are actually people of Hispanic ancestry. Unfortunately, Hispanics often have a higher risk for diabetes, the higher metabolic syndrome. However, according to the epigenetic clock, they actually age more slowly, you know, and so there is this really this disconnect. And this is actually an interesting disconnect because there's something known as Hispanic mortality paradox, you know. Hispanics, as I mentioned, have often a disadvantageous risk profile according to clinical biomarkers. But it turns out, on average, they live much longer than expected. They actually live longer lives than people of European ancestry, you know. And that association is paradoxical to a clinician who looks at clinical biomarkers. But according to the epigenetic clock, it's not paradoxical because, as I mentioned, we have found that Hispanics age more slowly according to the epigenetic clock.

Rhonda: That's very interesting. So, in this case, the epigenetic clock correlates more closely with lifespan than with clinical biomarkers and health status?

Steve: That's right. Yeah.

Rhonda: Well, in a way that's kind of good because you mean...

Steve: Well, it shows it adds something. And also, the epigenetic clock is actually very much under genetic control. Some people just inherit a genome that makes...or DNA that really allows the epigenetic clock to progress more slowly. And so, the heritability is about 40%, you know. So, in this sense, it's not just lifestyle factors. By contrast, some of the clinical biomarkers you mentioned are very much under the influence of lifestyle, you know. So, you can probably cure high glucose levels by just avoiding carbs, right? And also, high lipid levels by taking statins, you know. So, there are a lot of clinical markers that can be influenced with lifestyle interventions and pills. By contrast, we don't have many interventions that allow us to reverse the epigenetic aging rate.

Rhonda: But do we know that? We haven't been testing that though, right?

Steve: Yeah. I mean, not really. I mean, in my lab, we clearly want to find interventions that slow the epigenetic clock, and by now many people are working on it, you know. And it's a gold rush who comes up with an intervention that affects the epigenetic clock, you know.