Dr. Gundry (00:03):
Can you give the listeners a brief introduction of the ring and how it works?
Shyamal Patel (00:08):
Yeah, and the first generation ring, you describing it clunky is interesting. I would say it was a fashion statement. So just a brief history of Oura, Oura was founded in Finland in 2013. We are on our Generation Three product now. Generation One Ring was launched in 2015, Gen Two was launched in 2017 and Gen Three, our latest product, was launched in late 2021. Oura Ring is, as Dr. Gundry just showed, and I have a couple on my fingers, is essentially a wearable ring, it weighs about four grams and has a suite of sensors packed into it. These sensors are integrated into the Oura Ring to measure different aspects of your physiology, so there are three LEDs with three different wavelengths in the ring; red, green and infrared. These are in the ring for different types of measurements of the blood, essentially, that is flowing through your arteries.
(01:24):
We have an external meter and a gyroscope which measure your movement in three dimensions and we also have seven temperature sensors that make very high resolution measurements of your body temperature 24/7. The foundational or the first things you would experience if you had an Oura Ring would be these three scores; they’re readiness, sleep and activity. Readiness is essentially a score that tells you how ready are you for the day? Are you well rested, are you ready for pushing yourself, or should you take it easy today? It’s essentially a guide for you that tells you how you might want to go through your day and also helps you understand what are the factors that contributed to how you are feeling today, sleep being one of them?
(02:26):
Sleep is the second score, sleep score. It tells you basically how well you slept last night and that includes a bunch of different things; how much time you spent sleeping, the total time that you gave yourself the opportunity to sleep, how efficient your sleep was, was your sleep restful, how much REM sleep did you get? How much deep sleep did you get? Did it take you a long time to fall asleep? And was the timing of your sleep aligned with your circadian rhythm? So these are all these factors that contribute to the sleep score and it essentially tells you how you’re doing with respect to sleep and what are the things you can perhaps do to improve your sleep next night?
(03:11):
And then finally we have the activity score, which includes about, I think, six contributors. It basically tells you whether you have been staying active, are you moving regularly, are you meeting your daily activity goals? How frequently are you training and what is the volume of your training? And also, are you giving yourself enough recovery time? To essentially help let your body recover and get ready for activity again the next day.
Dr. Gundry (03:46):
So let me ask you one thing, my wife loves to tease me. She’ll say when we get out of bed in the morning, “How did you sleep?” And I’ll go, “Just a minute, I’ll let you know,” and I pull up the Oura results and she says, “That’s ridiculous. I want to know how you slept.” And I said, “Well this ring knows a whole lot more about how I slept than my perception of how I slept.” What say you, am I right, are you right, or is my wife right? This is all just fanciful thinking.
Shyamal Patel (04:27):
Yeah, no it is interesting. I think there are a lot of studies that have tried to compare how your subjective feeling of how well you slept or how you think you slept aligns with the objective measurements. The interesting thing is that these two things don’t correlate well. I mean you would expect them to, but they don’t. I think that is one of the reasons why having this objective data in addition to… I don’t think that how you feel is not important. It actually is very important and not just for sleep but for any aspect of your health as you know, you’re are a trained doctor, so you’d probably be an advocate for that. But when it comes to sleep, it’s the same thing. I think it’s important to know or understand how you’re feeling, but it’s also important to understand the objective aspects, the data behind what are the factors that may be driving how well you slept or how well you did not sleep? And I essentially identify some of the gaps between your perception of sleep and what your body’s experiencing during the night.
(05:32):
The other thing is that sometimes, you need this type of sleep depth to build up before you actually start feeling some of the effects, when with data, you can actually have a little bit of an early warning to warn you that you might be heading down a path that may be harmful for your health. I think one of the interesting things that sleep scientists are discovering is that sleep debt is not something that you can just pay off, it’s not, if you get two, three hours of sleep for a week just by sleeping more the next week. It’s not like you can just catch up. There is a deficit that can be sustained over very long periods and can almost have some kind of permanent impact on your health, especially when you have severe sleep deprivation. So data is, I think, not everything, but I think it’s an important aspect of understanding your sleep.
Dr. Gundry (06:34):
We were talking off camera, how has this sleep tracking technology evolved over time? Because this is now the Gen Three and you mentioned that Gen Four is on the way. What’s changed? What have you learned over the past number of years?
Shyamal Patel (06:54):
Yeah. So when Oura started in 2013, the focus was on sleep. So we’ve always had a very strong focus on measuring sleep and getting deeper insights for our users on how they’re sleeping and what they can do to improve their sleep. And so from a sleep measurement point of view, we have essentially been continuously at work improving how we measure sleep. Also, from a sensing point of view, how can we go get more accurate measurements? And so if you look at our evolution from Gen One to Gen Two to Gen Three, we have essentially added more sensors into the ring that enable us to measure more aspects of your physiology. We’ve also pushed towards increasing the resolution. One of the things that we have done in the most recent generation of the Oura Ring, which is an enabler for us to go to this more advanced algorithm that we are working on implementing right now into the ring, is simply increasing the memory, so we are doing more processing on the ring.
(08:08):
So with more sensors you’re capturing more data and in order for us to get the most out of that data, we also need more processing power and more storage. And so the same thing that is happening in the machine learning, deep learning world with the explosion of data and advancement of these techniques for processing this data, we are able to do some really amazing feats. And the same is true for what we are doing with the Oura Ring. So our next generation algorithm which you just mentioned is essentially taking advantage of all these added sensing capabilities in the ring along with really advanced computational capabilities that we are unlocking with the new hardware, and coupling that with advanced machine learning techniques to, I think, deliver the most accurate sleep tracking yet.
(09:04):
If you think about the history of measuring sleep, that is sort of the first, the polysomnography, which is the clinical standard for measuring sleep that was invented in 1973 or ’74. So it’s still relatively recent in terms of the ability to measure sleep. And again, polysomnography is something that has typically been performed in a sleep lab type of environment where you go in, you spend a night wired up, you have hundreds of electrodes and devices set up to you and then you’re asked to sleep in a strange new environment, and that’s been the standard in science of sleep. That is changing with more home sleep testing, but it’s still very cumbersome from a setup point of view. And so the science of sleep is also evolving and Oura has been leading the charge in terms of evolving the science when it comes to wearables. And I think we’ll continue to do that for a long time, I think.
Dr. Gundry (10:13):
Okay, let’s get back to sleep in general, hard charging Americans say, “Well I’ll sleep when I’m dead. That’s the least thing I have to worry about.” But in fact, we know that lack of sleep kills you. I mean it definitely shortens your lifespan. We know that Blue Zone people, in general, get eight to 10 hours of sleep a night and they actually frequently take naps. Where is the science now? Can somebody get by four to five hours of sleep or are they going to pay for it eventually, or is there a range where each of us needs? And how do you find that out? Big question.
Shyamal Patel (11:07):
Most people need seven to nine hours of sleep a night and there is variability. There are people who have this genetic mutation, it’s a very, very small percentage of people who may be able to get by with less than that. But most people by far, majority of the people need about seven to nine hours of sleep, and you’re absolutely right. I think we have a massive epidemic of lack of sleep that is going on, so the stats you mentioned were quite stark. One of the stats that I know is that one in five car crashes are caused by drowsy sort of driving, and that basically, just in the US results in about 7,000 deaths a year. So it is a matter of life and death literally when it comes to lack of sleep.
(11:59):
And then there are all these other potential long-term effects that has been linked with these proteins building up in your brain, beta-amyloids and taus and that are linked with potentially causing Alzheimer’s in the long term. And then there are also risks for hypertension, diabetes, it affects your immune system. So there is a whole lot of science behind sleep as probably one of the best things you can do for yourself to improve your health, and in multiple different ways, both short term improvements as well as longer term influences to your health. And around this aspect of getting enough sleep helps you improve your health, I don’t think there is much debate around that, at least from a scientific point of view. I think sleep is quite critical for functioning. It’s sort of like an essential biological need for humans and animals too.
Dr. Gundry (13:08):
Yeah, it is interesting. When I was a surgery resident, I remember when I went to the University of Michigan for my training and I came from Georgia Medical School where we actually as medical students worked through the night. And when I go into Michigan, the medical students on my service said, Well, it’s five o’clock, we’re going home now.” And I go, “What do you mean you’re going home? The most important stuff is going to happen tonight at two o’clock in the morning.” And they said, “No, we’re not allowed to be here at night. We have to get our sleep.” And I’m going, “Are you crazy?”
(13:54):
And this was a long time ago and they were actually way ahead of the curve, and now residency programs have controls on how long you can be on call, how long you can be awake. When I was chief resident, I went four days without sleep on the chairman’s service and then I slept for four hours and went at it again.
Shyamal Patel (14:22):
Wow.
Dr. Gundry (14:22):
And we now know that, “Wow, that’s like me driving a race car without sleep.” Clearly everybody had impaired judgment. Now, luckily, I don’t think I killed anybody, but that was sort of the culture and we now know that that’s crazy.
Shyamal Patel (14:46):
Yeah, no, absolutely. And I think that is one of our missions, what Oura wants to do is making health a daily practice. And I think the simple act of, you mentioned that the first thing you do in the morning when your wife might ask you, “How did you sleep?” And you go to your Oura Ring, and it’s this act of checking in, simply trying to be mindful about how did you sleep. I think for me, there are lots of benefits of Oura and the data and the insights, but the biggest one in my mind is this change in your mindset about checking in the first thing in your morning and thinking about, “How did I sleep? Let me understand this.” And I’m hoping that as more people use Oura Rings and in general, I think that the awareness of the importance of sleep becomes more widespread, I’m hoping that we will see improvements across a lot of these other aspects like long-term impacts on health and also the shorter term impacts that you sleep has on your ability to perform and be well during the day.
Dr. Gundry (16:04):
You mentioned something earlier that I think is an important message and I want to talk about that. Many of us have been taught that well, during the work week we have so much to do, we have to get it accomplished, we’ll work late into the night and we’ll catch up on the weekends, we’ll sleep in, and that kind of makes sense. But your findings and sleep study findings in general say no, that’s not the case. You literally cannot catch up. Is that true?
Shyamal Patel (16:43):
Yeah, I think catching up, you do see the pattern. If you look at patterns of people sleeping in during the weekends and we see that in the data of our Oura users as well. You see this pattern quite clearly; shorter sleep opportunity during the week and then people try to catch up during the evenings. And there are actually some really interesting cultural differences as well. If you look at people across different countries, you see different patterns sort of emerging. But I think that this pattern of people sleeping less, whether it’s weekdays or certain days when there is more work or stress and then trying to catch up, it happens and we all do that. I think we probably all, as you did give your example, I think we’ve all done that. The science, I think, is building up to say that it’s not that by catching up you are essentially erasing any of the negative impacts.
(17:45):
It probably helps in some ways to just catch up, so it’s not a bad thing to do to sleep more if you have been sleep deprived. But at the same time, building a lifestyle around this idea of, “I’ll deprive myself of sleep for a few days and then I’ll catch up during the weekend,” the science is increasingly telling us that, that is not a sustainable approach to sleeping. I think one of the most foundational things you can do for sleeping well and your health is to just build a very consistent sleep schedule. And I think that is also one of the things that Oura users learn very quickly is just build a consistent sleep schedule, introduce good sleep hygiene into your evenings, how you wind down. I guess if you start doing these things consistently, you know will see better sleep and better health as a result of it.
Dr. Gundry (18:47):
Part of this, I think, is we now know that we have multiple 24 hour clocks within us. We have a 24-hour clock in our brain, our gut microbiome operates on a 24-hour clock, and we obviously have clock genes in all of ourselves. And I tell my patients, “Essentially, you can’t beat the clock.” You may try to, but this whole idea that we should be in time with our circadian rhythms, I just got back from one of the major microbiome meetings in Paris, we’re more and more convinced that a large part, or at least a significant part of jet lag is actually our microbiome clock doesn’t catch up with our sunlight clock, and that it’s the lag in our microbiome that’s actually causing changes in the biochemical productions that they are affecting our brain with. So there’s still a lot to learn about all of this.
Shyamal Patel (20:01):
Yeah. No, I think the science is fascinating and there’s so much that we need to learn. And as I was mentioning, I think before we started recording, sleep has been thought of as predominantly a brain process, but it is a full body process in reality. I think that’s just how we’ve been measuring it. And as the science evolves, I think we’ll learn that sleep is connected to pretty much every aspect of our physiology and all the processes that happen in our bodies. So it is fascinating and that’s one of the reasons why I feel like Oura’s early focus on sleep was quite visionary. In 2013, if you think back, most of the wearables were focusing on counting steps or activity tracking and those types of things. Sleep was not necessarily a big part of the conversation. And so the foresight was quite remarkable in terms of focusing on sleep and really going deeper into understanding your sleep.
Dr. Gundry (21:09):
Okay, we talked about time of sleep, but probably more important, and I think you guys are really leading the way on this, is sleep efficiency, what happens from the time you go to bed till the time you get up the next day. I mean come on, I go to bed, I go to sleep and then I get up. That’s pretty simple, but you are saying there’s a lot happening that you probably ought to know about during that time period. So what’s sleep efficiency?
Shyamal Patel (21:46):
Sleep is a fascinating process and I think that in terms of learning, I’ve probably just scratched the surface of how sleep is from a function point of view and the physiology of sleep and things like that, so a lot happens during sleep. Sleep efficiency, to answer your specific question, sleep efficiency is a very simple metric that just tells you how well did you sleep. So it is essentially describing the amount of… Essentially, you went to bed and you woke up. In between that time, how much time did you spend sleeping? So when we are sleeping, we go through these stages. At a high level there are four stages of sleep; wake, REM, light and deep, and light and deep can be subdivided into two more stages each, so and N1, N2, and N3, N4, and again, I can talk more about that. But at a high level there are these four stages and most of our nights we cycle through these stages, and typically I think we experience about four to five 90-minute cycles of these stages, sort of these cyclical patterns.
(23:04):
And essentially, efficiency tells you how much of this time were you in the wake state and how much of the time was spent in the rest of the stages. So it’s a high level metric but it’s a very powerful metric that tells you how well you are sleeping. When you are giving your body the opportunity to sleep, how well are you able to take advantage of the opportunity? And then, from sleep efficiency, you can go deeper into understanding when you are sleeping, how is your sleep architecture, how much time are you spending in your light sleep, REM sleep, deep sleep. Each of these stages has their own significance in terms of the benefits and what they do for your body and mind. And so sleep efficiency is the first place you would want to start, but then, you’d also want to go deeper into how you’re sleeping in terms of the stages.
Dr. Gundry (23:58):
So I notice, particularly when I’m sleep deprived, when I’m up with a patient or something, or time zone travel, I will frequently, the first few nights after these episodes, have a lot more deep sleep. Personally, I like deep sleep. I think, and others think that that’s when we do our brain cleaning, our glymphatic wash. And so to me, it’s actually a confirmation that, “Hey, your brain took a hit in terms of its repair functions and good news, your brain’s catching up on its cleaning function.” Is that just a fanciful thinking, or can you see those things?
Shyamal Patel (24:52):
No, you do. So for example, if you push yourself and work out harder a day, you will see potentially increased deep sleep during the night. You’ll also see reduced latency in terms of falling asleep. You’ll fall asleep faster because your body is just craving for that sleep. And then what you would see is most of the deep sleep is preloaded into the night. So the first half of your night, that’s when you get most of your deep sleep and you’ll see that if you’re very tired because of physical exertion or other types of exertion, then you would quickly get into that deep sleep stage and it’s likely that you would see more deep sleep when you’re trying to recover from different stressors.
(25:43):
Typically, if you’re going through your normal life, normal daily life without these types of exertion periods, most adults would see about 15 to 20% of their sleep time they spend in deep sleep, and this decreases with age. So as you age, you’ll spend less time in your deep sleep. So it’s not like you always need to have a fixed… There is an age component that will also play a factor. And you’re absolutely right, deep sleep is remarkable in the restorative power from things like muscle growth and repair to cleaning up your brain and flushing out these proteins that are building up through the day. It’s also important for your metabolic health and function. I think you probably know a lot more about that than I do. And also immune system, I think kind of healthy functioning immune system, deep sleep is quite critical to that as well.
Dr. Gundry (26:48):
I and others, including Dale Bredesen, the author of The End of Alzheimer’s, and David Perlmutter, think that we really should try to avoid eating for preferably three hours before we go to sleep. Do you guys see an effect of eating close to bedtime? Either changes in sleep or do you-
Shyamal Patel (27:16):
Absolutely, yeah. No, absolutely. I think late meals are one of the key factors that you know will notice if you use an Oura Ring, you have a late meal, you will see it in your data and you can actually just, besides your sleep staging data that tells you more about how you slept. If you go to your physiology data, if you look at your heart rate, in the Oura Ring, you can actually see your trend, you will see that your heart rate will stay elevated for a longer time and it’ll take longer for your heart rate to go down if you had a late meal. And basically, what is happening is your body is in the under stress processing that food and that late meal, and it is having an impact on your ability to get good sleep.
(28:08):
So what I think we have found from a scientific point of view that people who sleep eat early and eat a smaller meal in the evening, they tend to have better sleep. They tend to sleep better because their body is more ready to go to sleep and take advantage of that opportunity that it’s getting. So yeah, absolutely. Caffeine is another factor, keeping your environment cooler. One of the things that happens when you go to sleep is your body temperature lowers, your core body temperature, and that is essentially preparing your body to get to sleep. And one of the ways you can promote that is by creating a cooler environment for you to sleep in. If your environment is on the hotter side or warmer side, it is going to make it harder for your body to sleep. And that is, again, one of the reasons why we have a temperature sensor in the ring is temperature is a very key metric to track in order to understand sleep and how well you’re sleeping.
Dr. Gundry (29:15):
So what you’re saying is, my wife’s mother told her that you always had to sleep with the window open, and so you’re saying that that old wives’ tale pro probably has some truth to it?
Shyamal Patel (29:27):
Yes, and the same reason why taking a warm shower before going to bed also promotes sleep is because when you take a warm shower, from a thermoregulation point of view, your core body temperature is going to go down in response to the heat. So that actually promotes exactly that phenomenon.
Dr. Gundry (29:55):
All right. So you mentioned you’re measuring temperature on the finger. Let’s suppose I sleep with my hand outside my pillow and it’s up above my head and it’s a cold room, how do I know that that’s my core temperature? What have you done to correct for that?
Shyamal Patel (30:18):
Yeah. So first thing, we don’t measure your core temperature, we measure your finger temperature. There are actually some really interesting properties of measuring your temperature on your periphery when the palm… Most of the sensing that happens in the Oura Ring is on the palm side of your hand, all of our heart rate, where we sense how the blood is flowing through your arteries, that happens on the palm side, temperature sensing happens here as well. And this heat exchange, a lot of that happens through your arm. And so the phenomena that we measure is actually opposite to what is happening at the core. So when your core body temperature is dropping, the temperature on your finger is actually going up, so we see the opposite phenomena. The other interesting thing is that while your core body temperature doesn’t fluctuate significantly, I think we see about two to three Fahrenheit change in your core body because your body wants to keep… You don’t want to see large fluctuations there, but on the finger you see a much larger change.
(31:38):
So the signal that we are getting on the finger, the amplitude is much larger compared to what you see in the core in terms of just the magnitude of change. And what that does is, while we are not measuring your core body temperature, what we are measuring is a very high quality analog of a signal that is telling us how your core body temperature is changing, which direction and it is very, very sensitive. And so in terms of an algorithm and how we use that data, one of the things that we do, and we do this for a lot of our metrics as you probably have noticed, is we build a baseline for you. So that baseline is based on long-term days and sometimes even weeks of data. And one of the ways we account for these factors, one day, let’s say you decided to sleep with your hands under the blanket, one day you decide to sleep… There are different things that could happen.
(32:37):
But what we do is by using a long term baseline to adjust for these steps of smaller variations and also, during the night when we are using your temperature, we are actually processing temperature data in a way where we are trying to deal with these types of artifacts or outliers. So there are some interesting processing techniques as well as this sort of approach for using long-term baseline data that enables us to really do a good job in terms of understanding how your temperature is fluctuating day to day, and even within the night.
Dr. Gundry (33:17):
All right. Since I mentioned my finger, why did you guys choose a finger rather than most of the other tracking devices, whether it’s an Apple Watch or a Fitbit or a WHOOP, are worn on the wrist? I mean why the finger, other than it’s incredibly attractive?
Shyamal Patel (33:40):
Yeah, so I think I would say there are three reasons. There are three factors behind that choice. One is associated with kind it’s an incredibly easy form factor to get used to. When you are getting a wearable device, any device, any new piece of technology, the first thing, there’s a period in which you need to adapt to that technology to get used to it. And with wearables, one of the big factors is that a lot of people buy wearables, wrist worn wearables, and a lot of people don’t make it through beyond a few weeks. They end up in your drawer and just, people forget because just the getting used to is harder. The finger form factor has been remarkable in its capacity for people to get used to very, very quickly. And so what we see is within the first week, it becomes of sort of a second nature to use the ring, so that’s one.
(34:48):
The second one is this aspect of the signal quality. So when you are talking about health tracking, and as a doctor, you probably appreciate this quite a bit, is that you want the best information possible in order to make decisions about health. The same is for the Oura Ring or any variable. The better information you have, the better signals you have, the better information you’re capturing and the better insights you’ll be able to deliver. And so the fact that we are making all these measurements on the palm side of your hand helps us deal with things like skin tone.
(35:24):
On the palm side of your hand, the skin tone factors are less prominent compared to when you’re making measurements on the wrist. You also don’t have other things like hair, other factors that are impeding these measurements. The other thing that helps is that when we are measuring on the palm side, we are actually measuring directly from your digital arteries that are flowing in your fingers. Most of the wrist worn devices are measuring from capillaries that are located on the back of your hand. So in terms of just the power that you need from a signal point of view to get similar quality data, we are an order or two magnitude lower in terms of when we are making measurements on the finger. So higher accuracy and higher quality of signals, that’s the second reason.
(36:17):
And the third reason is sort of this idea of, it’s I guess maybe more philosophical, which is with Oura Ring, our philosophy is that we want to be there for you when you need us. When you can’t see notifications, Oura Ring doesn’t distract you, it doesn’t. When you need the data and when you want to understand what is going on with your health, how you’re sleeping, et cetera, Oura Ring is there, otherwise it sort of blend in your background. It’s sort of transparent from a technology perspective. So I think those are the three main reasons I think that has driven our choice of the finger form factor and the ring form factor. And I think that has driven a lot of the success we’ve had in terms of health tracking.
Dr. Gundry (37:10):
All right. I think one of the exciting areas that you’ve pioneered and others have caught up a bit is heart rate variability. I was actually involved, years ago, as a principal investigator in a study looking at who should get automatic implantable defibrillators and people have heard about defibrillators with senate candidate Fetterman who got a defibrillator. But we looked at who should get those based on heart rate variability in people with ischemic heart disease.
Shyamal Patel (37:55):
Mm-hmm. Interesting.
Dr. Gundry (37:56):
And we found, interestingly enough, that low heart rate variability was very predictable, was a good prognosticator for your risk of sudden death from fibrillation. And it was actually one of the things that correlated well with who we felt should get a defibrillator. So I’ve always been fascinated with heart rate variability. Years ago I was presenting at a mindbodygreen meeting in Tucson, Arizona, and one of Oura’s people, a young man from Finland, and I were talking about heart rate variability, and I was showing him mine. And mine usually runs 70 to 80. If I’m very vigorous in exercise programs, I’m 130, 150, which I view as a good thing. And he’s showing me his data and he’s 270 and I’m going, “I hate you. How do you do that besides the fact that you’re 25 years old?”
(39:12):
And my wife, who is actually a great athlete, big time former marathoner, her heart rate variability is in the twenties, and she says, “Oh my gosh, I’m going to die soon.” Well, she’s not. But explain heart rate variability and why I should be interested and explain to me how I can help my wife, number one. And number two, I have a number of patients who have low heart rate variability and yet they’re actually pretty impressive athletes. I’ll just use my explanation, my wife has a V8 engine that lumbers along, I mean her resting heart rate is like 42. And I said, “You’re just a big lumbering V8 and your RPMs are so low that, that’s you. Me, I’m a turbocharged four-cylinder and when I really need it, I can get the gas going but I need a lot more. I’ve just got a smaller engine.” Is that just making it up for her, or what do you think about heart rate variability?
Shyamal Patel (40:28):
Yeah, heart rate variability is fascinating. I think in the science around heart rate variability and how to interpret it and what it means for your health, I think a lot of the work has been happening in the last few years, to be honest. Especially, I think wearables have been a big driver for HRV awareness. HRV is not something that people, I think maybe five, 10 years ago, they thought about on a regular basis. Now it is becoming, and it is quite a powerful metric, as you mentioned. When you were describing that you were using this for important medical decisions back several years ago-
Dr. Gundry (41:14):
This was 20 years ago.
Shyamal Patel (41:16):
20 years ago. I mean I’m not surprised that you were ahead of the curve there, but also, it’s just fascinating to see that there was, if you have people who are experts and who had that understanding, maybe they were using that metric for some decision-making. And I think I expect that HRV is going to become something that we will probably start tracking from medical records’ point of view as well as a metric over time. I think it’s quite powerful. Just for the benefit of the listeners, heart rate is essentially measuring how many beats per minute your heart is beating. And it can be higher, it can be lower, and there are lots of factors why that would be. HRV is essentially measuring how regular is your heart rate.
(42:17):
If your heart rate is 60 beats per minute, it doesn’t mean that every second your heart is beating, it’s not like a metronome. There is going to be variability. So it could be like 0.9 seconds, 1.1. Between beats, there could be variability and that is what heart rate variability is essentially measuring, how consistently your heart is beating or how much it varies. And surprisingly, interestingly, higher the heart rate variability, the better. That’s generally how we think about it.
(42:54):
And your heart rate variability is quite fascinating, and heart rate variability typically declines with age and for your age group, you will probably be in a very high percentile from a heart rate variability point of view. I think generally speaking, higher heart rate variability indicates better heart health and better sympathetic, better sort of balance in your autonomic nervous system. But I think there’s also, in terms of interpreting HRV, I don’t think we should get caught up in absolute numbers. I think it’s better from my point of view to think about what your heart rate variability is, and it could be in the twenties or thirties or it could be like you, 70, 80, or it could be this person from Finland, a super fit athlete probably, who might be high. And that’s a very extreme, right?
Dr. Gundry (43:50):
Good.
Shyamal Patel (43:53):
But at the end of the day, how I think about heart variability is that tracking heart rate variability is extremely important. It tells you about how well you’re recovered, are you busy your body in stress or not? And it’s a good metric, just the changes in your heart rate variability, up or down, related to your baseline, gives you a good indicator of that. And there are things you can do to improve your heart rate variability. It’s not something that, if your heart rate variability is 30, it’s not like you can double it, but you can improve it if you improve your diet. There are factors like exercise and getting fitter. Those are things that could move the needle from a heart availability point and help you get healthier.
(44:42):
But again, the example of your wife who’s an extremely fit athlete, nothing wrong, I think her heart rate variability, and I don’t know how much room she has, if she’s already super fit, to change that. I think until more science builds up and helps us understand what are some of the risks, if you are a super fit athlete with your resting heart rate in the forties, which is phenomenal, and your heart rate variability is 30, it’s not a cause of concern. We don’t have the science to build that kind of correlation or insight. But right now, I think we do understand that paying attention to your heart rate variability, the balance of your heart rate variability, and that’s actually one of the contributors we use in calculating your readiness score.
(45:40):
It’s essentially, how is your heart rate variability changing compared to your baseline? If it is a little bit better than your long-term baseline, that’s great. If it’s a little bit lower, we tell you that you might want to pay attention, what is going on? It could be illness, it could be stress, it could be that you’ve been pushing yourself too hard and not giving your body enough time to recover. So there are lots of factors. So I think my general advice is that not thinking about HRV in purely absolute terms, follow the science and let the science build up and help us understand more about how we want to use this. But I think that HRV is going to be a very important metric that I think everybody will pay close attention to in the future.
Dr. Gundry (46:28):
In a similar vein, as a nutritionist, I got to ask, can this data guide us in food selection? What foods are affecting us positively, what foods are affecting us negatively, or do we not have enough data?
Shyamal Patel (46:48):
Yeah, I think I would say the data is building up. We talked about late meals as an example, that you could also get some insights into the quality of your meal. If you’re having a meal with a lot of sugar, desserts, you will see a difference between a healthier meal. Even if it’s a late meal, you will actually probably see a difference in your physiology that will tell you something about the stress that a meal put on your body. But I think the science is evolving.
(47:25):
One thing that I’m particularly excited about is people who are looking at data from wearables like the Oura Ring in combination with CGMs and food logging and tracking to really understand the association between nutrition, your sleep, your activity levels, your physiology and your ability to control your blood glucose. And I think there’s some really fascinating insights that will come from that type of work that will help us, I think understand and more at a personal level, how are different dietary choices affecting our health. I think I’m quite fascinated about that aspect and I’m actually curious to hear what your thoughts are on that since this is such a big focus area for you.
Dr. Gundry (48:20):
No, I think we certainly see people with high sugary food intake, particularly late at night, you’re right, their heart rates are often through the roof and are very slow to come down, and I think that’s actually a good variable. We know that the longer it takes you to digest food, we actually put a huge amount of cardiac output into our digestive tract to facilitate digestion and absorption. I think and others think that, that, particularly at night, should be directed to your brain for brain cleaning and brain washing. And I think a lot of the evidence of this late meal, or even snacks before bed being detrimental is because our heart output, cardiac output, is directed in the wrong place and it should be going to our brain and our muscles for repair during the night. And if it’s down in our gut, it’s in a way very detrimental.
(49:34):
I think it’ll be very interesting to also see, I know you guys are tracking predictability of illnesses, predicting the onset of an illness, and I think there’s actually a lot of value here. We’ve noticed through the years that we measure several markers of inflammation. I’ll just bring up one, which is hs-CRP, and we see our patients, they get their blood drawn about two weeks before we see them. I’ll be a prognosticator and I said, “You got sick a couple of days after you got your blood drawn,” and they said, “Yeah. How did you know that?” And I said, “Well, your C-reactive protein and your fibrinogen was up,” and they said, “Well, but I wasn’t sick when I came in. I wouldn’t have come in.” I said, “Well, I know, but it was actually happening in you and we saw it in your blood work, but then it appeared.” And I think you guys are now getting pretty good at showing previews of something that’s happening that you may not be aware of, is that correct?
Shyamal Patel (50:49):
Yeah. Yeah. And this has been some phenomenal work that has been done by researchers across many institutions over the last couple of years. And also, a lot of work that we have done at Oura that has shown that there is really some predictive power in these metrics. And again, going back to this idea of building your baseline, which is what basically we do. When you get an Oura Ring, the first couple of weeks we are building your baseline and then that baseline evolves with you, it’s not a static baseline. And what that enables us to do is to look at these even small changes that are occurring related to your baseline, give us an idea of something might be going on. And when we see these changes that happen consistently, like today there was a little bit of change and then tomorrow there was slightly bigger change, that has the power and we’ve seen this association that we can see two and a half to almost three days ahead of the time you start feeling symptoms and go get a test.
(51:57):
We can’t say whether you have COVID or flu or what illness it is, but we do see that there’s something stressing your system and that you may be coming down with an illness. This was something that actually, I think there was a Finnish entrepreneur in March 2020 who was traveling in Europe, so this was early days of COVID, and one of the things that he noticed was that Oura, the readiness score was in fifties and his typical readiness score used to be eighties or nineties. And he also noticed that there was about a one degree Celsius, so a 1.8 Fahrenheit increase in his temperature deviation. So he put those two things together, went to get a COVID test and tested positive. So that was the first known case of somebody who looked at their Oura data, thought something was off, even if he was feeling fine, he was not feeling anything specific, and then he obviously developed symptoms.
(53:01):
And then there have been several large studies, there was a massive study at UCSF called TemPredict with more than 65,000 Oura users participating in that study, contributing their data. There was a 10,000 person study that the Department of Defense did with their Defense Innovation Unit and also a large study that was done at West Virginia University in the Rockefeller Neuroscience Institute in about, I think a thousand or so healthcare professionals. And all of these studies have consistently shown that the ability of data from the Oura Ring having this sort of predictive power. And we’ve actually built up a commercial solution that organizations are using, MBA was using during the pandemic to manage the risks of spreading infection.
(53:56):
So I think this is really fascinating, again, an area where the science has literally built up over the last two, three years. But what the potential is, is quite fascinating, and you could imagine a scenario. I think there was a paper in Lancet recently from the Scripps Institute where they were talking about how data from these types of wearables could be used as a sort of early warning sign of potential pandemics that could be spreading, just by looking at these patterns of people coming down simultaneously in regions that could be some really powerful applications in the future.
Dr. Gundry (54:39):
I think from my standpoint, I actually am impressed with the power of vitamin D to break viral illnesses, and I think if we had that sort of data that, “Hey, there’s something about to happen to you, let’s preemptively go after it with, for instance, high dose vitamin D,” which is what I do. But I’m not saying everybody should, but that’s what I and my family and my patients do. But getting this information early and then acting on that information, I think is even more powerful as we go towards personalized medicine.
Shyamal Patel (55:16):
Exactly, yeah. And a big, big, big role that we think we have to play at Oura is in health education. So yes, we are a health tracker and you can look at your data and all that, but ultimately what we are doing is helping you educate yourself about your health, what these metrics are, how they relate to your health, and how you can make better decisions. And I think that’s, if you think about a larger sort of vision, that’s essentially what… And I think it’s going to be fascinating to see people become more aware and use the data that we are capturing with Oura Ring in these ways that are going to be quite fascinating from the future of health perspective.
Dr. Gundry (56:00):
Yeah.
(56:01):
The next episode or the Dr. Gundry podcast is waiting for you now.
(56:06):
Believe it or not, some of the best ingredients, nutrients, in citrus are actually in the white pith. That’s the stuff that you peel off and throw away.
