Have personally long been fascinated by the predictive value of HRV. At the level of the individual, though, remains hard to tease out underlying genetic differences vs modifiable factors vs unique physiologic risks. My general thought is, if in the course of your in depth medical evaluation of someone you can't find a cause for a low HRV, to favor it being idiosyncratic and choose to monitor trends as opposed to absolute values.
Also personally think that some of the interventions, such as vagal stimulation, may go farther in goosing the test as opposed to treating the underlying physiology. Sort of like the grip strength thing, where grip strength is likely more reflective of overall strength and ability to apply it than grip strength being uniquely associated with longevity; thus, specifically training grip unlikely to have a profound effect.
One last note - do you still microdose a GLP? I believe you had posted about that before, but if I'm mixing you up with someone else, apologies. Those pretty reliably drop HRV, even in small doses.
Hi Chris, thanks for these comments, agree. Is there a reference for HRV and GLP? I do intermittently take GLPs these days at a low dose. I like the potential longevity and brain benefits and the appetite curbing but I am worried about the cosmetic issues some people have (ozempic face) and it does reduce hedonic tone of food and other activities. So I'm sort of splitting the difference currently by taking a low and intermittent dose.
To be honest, the decrease in HRV with GLP is something I picked up from observation in patients and talking to other docs as well. Just did a little snooping online and found the below study. Lots of qualifiers about size, using wearables, etc, but I think it generally tracks with what I've seen:
While the HRV is one data point to note, my sense is that the net benefit for the GLPs is really high. I think:
-we should probably not over index on one marker (HRV in this case) especially when that marker has some confounds and is very complex to interpret
-GLPs have been pretty clearly shown to have net cardiac benefits, even independent of weight loss.
Other benefits too - seems like they might be good for cartilage, anti inflammatory, possible neuroprotective benefits, etc. And I've had too many patients tell me they just make them "better" or more like the person they want to be: less food cravings, less urge for alcohol, etc.
Personally planning to start microdosing soon.
Just my two cents. Really appreciate your extraordinary work on this blog!
To be honest, I don't really know. We know there's GLP receptors everywhere and that these are functional neurological drugs as much or more than they are GI drugs. HRV is functionally an indicator of the balance between two neuro symptoms, so... doesn't shock me that there would be an effect.
Good article. I have been tracking HRV with Google Pixel 3 watch for the past few months but hadn't really read anything about the ranges you showed here based on age.
Great stuff, Dr Glorioso.
Have personally long been fascinated by the predictive value of HRV. At the level of the individual, though, remains hard to tease out underlying genetic differences vs modifiable factors vs unique physiologic risks. My general thought is, if in the course of your in depth medical evaluation of someone you can't find a cause for a low HRV, to favor it being idiosyncratic and choose to monitor trends as opposed to absolute values.
Also personally think that some of the interventions, such as vagal stimulation, may go farther in goosing the test as opposed to treating the underlying physiology. Sort of like the grip strength thing, where grip strength is likely more reflective of overall strength and ability to apply it than grip strength being uniquely associated with longevity; thus, specifically training grip unlikely to have a profound effect.
One last note - do you still microdose a GLP? I believe you had posted about that before, but if I'm mixing you up with someone else, apologies. Those pretty reliably drop HRV, even in small doses.
Chris
Hi Chris, thanks for these comments, agree. Is there a reference for HRV and GLP? I do intermittently take GLPs these days at a low dose. I like the potential longevity and brain benefits and the appetite curbing but I am worried about the cosmetic issues some people have (ozempic face) and it does reduce hedonic tone of food and other activities. So I'm sort of splitting the difference currently by taking a low and intermittent dose.
To be honest, the decrease in HRV with GLP is something I picked up from observation in patients and talking to other docs as well. Just did a little snooping online and found the below study. Lots of qualifiers about size, using wearables, etc, but I think it generally tracks with what I've seen:
https://journals.physiology.org/doi/full/10.1152/ajpheart.00809.2024
While the HRV is one data point to note, my sense is that the net benefit for the GLPs is really high. I think:
-we should probably not over index on one marker (HRV in this case) especially when that marker has some confounds and is very complex to interpret
-GLPs have been pretty clearly shown to have net cardiac benefits, even independent of weight loss.
Other benefits too - seems like they might be good for cartilage, anti inflammatory, possible neuroprotective benefits, etc. And I've had too many patients tell me they just make them "better" or more like the person they want to be: less food cravings, less urge for alcohol, etc.
Personally planning to start microdosing soon.
Just my two cents. Really appreciate your extraordinary work on this blog!
And what would be the mechanism of GLP dropping HRV? That’s pretty interesting
To be honest, I don't really know. We know there's GLP receptors everywhere and that these are functional neurological drugs as much or more than they are GI drugs. HRV is functionally an indicator of the balance between two neuro symptoms, so... doesn't shock me that there would be an effect.
A short search yielded this study:
https://pmc.ncbi.nlm.nih.gov/articles/PMC3002870/
In mice, trying to identify some of the mechanism re GLP/cardiovascular effects. Not sure how translatable this is, but it's interesting.
Good article. I have been tracking HRV with Google Pixel 3 watch for the past few months but hadn't really read anything about the ranges you showed here based on age.
Ultra-processed food can also affect HRV and trigger a form of food-induced brain dysfunction: https://carbsyndrome.com/