Dr. Satchin Panda 0:00  
Try to maintain a regular time to go to bed and be in bed for eight hours so that you can get six to seven or seven half hours of sleep because when you sleep well, your brain and body actually repair itself much better for the next day.

Claudia von Boeselager 0:18  
Are you ready to boost your longevity and unlock peak performance? Welcome to The Longevity and Lifestyle Podcast. I'm your host, Claudia von Boeselager, longevity and peak performance coach. Each week, we'll explore groundbreaking science, unravel longevity secrets, share strategies to grow younger, and stay up to date with world-class health and peak performance pioneers. Everything you need to live longer, live better, and reach your fullest potential, ready to defy aging, optimize health, and promote peak performance. Visit LLinsider.com for more.

My guest today is Professor Satchin Panda, a world-renowned circadian rhythm researcher and leading authority in the field of chronobiology. You might also know the concept of time-restricted eating, aka intermittent fasting work that came out of his lab with a passion for understanding the impact of our internal clocks on health and well-being. Dr. Panda has dedicated his career to unraveling the intricate relationship between circadian rhythms, sleep, and overall human physiology. Through his groundbreaking research, he has shed light on the effects of disrupted sleep-wake cycles and artificial lights on our health, offering practical strategies to optimize our daily routines. He is a professor at the Salk Institute and founding executive member of the Centre for Circadian Biology at the University of California, San Diego. Please enjoy our talk today on optimizing your health and longevity using circadian rhythms. Welcome to The Longevity and Lifestyle Podcast, Professor Dr. Satchin. Such a pleasure to have you on today.

Dr. Satchin Panda 2:05  
Yeah, I'm happy to be with you on this podcast.

Claudia von Boeselager 2:08  
So I'm very excited to have you on, obviously, I've been following your work for several years and being in this space. And I heard you present last year at the Health Optimization Summit in London. But I really wanted and I'm delighted that we could make this this time to really bring the concept of your work and what it's doing and the implication because it is just so important for every single person to understand better out to the world. So, let's start with the concept. As you are the world leader in circadian rhythm. Can you explain exactly what the circadian rhythm is and why is it so important for our health and well-being?

Dr. Satchin Panda 2:48  
So the words you carry on actually literally mean nearly 24 hours. So that means anything that we experience or our body goes through once every 24 hours is considered a circadian rhythm. And we always think of we're always told that our DNA holds the blueprint for our bodies, just like any blueprint for building the DNA course everything but what we forget is when you build the building, whether it's an office building versus school, it's not a dry building, it actually has life into it. So, something happens during the day something happens in the night. And you look at any building that has specific tasks happening at a specific time of the day. So, for example, before the office starts, the custodian staff would come in and clean up the place and then the cafeteria people and then they will come and brew the coffee and then people also are the shipping and receiving would come So, similarly, what happens is nobody a body is not static. And we know that what I am in the middle of the day and who I am in the middle of the night and very different. So, the basic concept is just under this seeming sleep-wake cycle, our body actually goes through a huge number of changes between the night and if we think of every hormone, every brand of chemical, every immune response or immune modulator, every Jain digestive or anything else, even every single gene turns on and off at the specific time of the day or night. So then the question is, why are these rhythms these rhythms essentially do a few things one is the consolidate similar tasks like for example, when out when you are awake, which are muscle points or be better so that we go running just imagine if your mouse photon is much better in the middle of the night, then you'd be happy to have all your dreams

Claudia von Boeselager 5:05  
kicking around the place.

Dr. Satchin Panda 5:06  
Yes. So, the second is separating incompatible processes. Same thing, as I said, your muscle pumps will be compatible with the daytime or nighttime. Similarly, our bowel movements should be in the first half of the day after waking up and cleaning up our bowels so that we are ready for food. So even at a very complex level, like genes and proteins, we do see these things. And then the third one is anticipation. So for example, in anticipating waking up, your heart begins to increase your body temperature begins to rise slightly. So it prepares your body for the next act in the day, and cannot prepare. Just imagine if you're not prepared for your, for your exam if they're not prepared to go to the doctor's office. So, circadian rhythms repair all of this. So then, the bigger question for everybody. So what? Why should we pay attention to it? This is so hard thing actually relates to why we cannot live a long healthy life. I mean, if we're designed to have this DNA to give us this perfect body and mind, why we cannot leave? The reason why we can't live a long healthy life relates to four major types of disease. The first one is an infectious disease, everybody can relate to because we all came out of COVID. But there are many more infectious diseases that make us sick. Second is the metabolic disease, obesity, and diabetes, starting from there to cancer, all of which affect millions and billions of people. This isn't why almost one in two adults in the US or in the Western country is going to experience at least diabetes. One and two are going to experience high blood pressure, four out of 10 will be diagnosed with cancer, all of these vaccines are going to add, then the third one is brand health. The statistics are very different because at any given time, five to 15%, of people might be experiencing depression or anxiety. But in our lifetime, if we take the entire lifetime, 85% of us will experience or have experienced some kind of depression anxiety, which is clinically significant clinical depression, anxiety, or PTSD. And then the fourth category that I say is injuries. We know that, for example, I just crossed 50, a couple of years ago, and the reason why I cannot run as fast as I could or I want to, or why I cannot lift certain things is because I have certain injuries. And as we get older, we accumulate injuries, and that also reduces our performance. So getting injured and coming back to full play is what we need. So what is interesting is over the last 3035 years, scientists all over the world are very few scientists who actually work on CKD under them, but they're really smart scientists. And we figured out that circadian rhythm actually optimizes our health so that a body can better fight infectious disease. And so can it can actually if we have good strong security and the day-night cycle, then we are also more likely to prevent chronic diseases from diabetes, obesity all the way to cancer, even dementia. We can even combine the principle of circadian rhythm with whatever treatment you are doing right now that Szilard cures, and come back to full play. Similarly, it's become very clear that certain principles of circadian rhythm for example, sleep, maintaining proper sleep-wake cycle, maintaining enough light exposure during the daytime, avoiding light at night, and combining that with proper timing of nutrition, etc. can also reduce the severity of depression, anxiety, and brand improved brand health improve mental performance. And just recently, we are beginning to understand that many of the injuries prevent and prevent injury and then come back to full play, whether it's bone injury, whether it's muscle injury, all of these injuries. Having a strong circadian rhythm also helps us to better prepare ourselves and having a strong security under them and having physical activity at the optimum time also proved Events injury. So that's why I'm looking at almost every health concern for everyone through the lens of circadian rhythm there isn't is; this is such a powerful concept. And it doesn't cost anything to adopt this into our lives; of course, you can spend a little bit of money to optimize your circadian rhythm. But this is something that we can the solution is now it's right now. And you could just understand how these rhythms are regulated, or how we are the master conductor of this residence. Through when we fast when we sleep when we wake up, and when we get exposed to light. And when we exercise a few simple things, then we can actually leverage the power of the circadian rhythm. And I'll give you some specific examples. But this simple attention to security under them is even more powerful than the best medication available.

Claudia von Boeselager 11:03  
Yeah, and I'd love to hear those. And what you just said is just so powerful that not only can it help to optimize, but it can reverse so many of these chronic diseases that are affecting so many people. And everyone I think has some connection to one. My mother has dementia, my father has cancer, have relatives have issues. And, you know, the beauty is that when you understand this model, I'd love to hear some use cases as well as that you've seen some transformations. But I'd love to break it down. How does one master the rhythms as you were saying, you know, how does one understand if they're off balance and be? What is the right time for the individual? Because we are all different?

Dr. Satchin Panda 11:48  
Yeah, I guess you are asking a very fundamental question, What are these rhythms, and how do our lifestyle or what we do affect these rhythms? So it all boils down to one fundamental reason why we have these students. For the last 200,000 years, we humans have been living on this planet, and for almost a billion years, other life forms on this planet. And over the last billion years, you may argue, okay, so there was global warming, global cooling, and all that stuff. But seasonal changes, but there's only one constant to that billion years, that is sun came up, went down and that object, approximately after 44 hours, the sun came up again. So it's a very powerful cycle of light and darkness. And with light and darkness can result in warmer temperatures and cooler temperatures at night. And also access to food four times per day active animals like us have access to food during the day, and mostly fast at night. And then, for people for animals and humans who are there, they have to run back at the end of the day to go to safe places to hide and run home. So these very fundamental rhythms and getting exposed to light during a minimal light or darkness of night. That's one reason second, eating mostly during our wakeful hours during the day because, in the old days, there was no processed food and preservation. Then telling it overnight fast at night, then having all this lot of physical activity towards the end of the day, those were the only constant that actually happened for the last 200,000 years for humans. So as a result, our genome, our physiology, our metabolism, our brain function, everything is tuned to this cycle. And just imagine, we cannot live outside this modern world for a few days. Imagine if we, I cannot imagine if you drop me in the middle of some wilderness where there are no modern amenities survived that, yeah, I can survive that for even more than a week or a month. And just imagine our ancestors didn't live up to say, 2025 40, Sometimes 4045 years, because they built that resilience against disease against injuries against all the metabolic diseases that we are talking about. And also they have to be a lot they cannot be depressed the lion will come and kill them. So all these things were there. So now the question is you cannot go back to that ancestral life because our modern life or modern way of living actually forces us to be active at night. To are more exposed to light at night, and we have access to food all the time, and we are sedentary. So now the question is, we can't give up the life of the modern world. Creating wealth is synonymous with breaking our circadian rhythm, you cannot expect to make a lot of money and be rich, or bring enough for your living to, to pay for your family by just going to bed at seven o'clock in the evening and working.

Claudia von Boeselager 15:34  
Unless you get up at 4 a.m. Maybe. Yeah, so the

Dr. Satchin Panda 15:39  
The point is, how do we manage this? And then, who is getting disrupted? And how do you understand that you are disrupted? So let's begin with a very simple thing, if you're sleeping less than seven hours, you already have a problem with circadian rhythm disruption. So many of us can relate that if you sleep for poor kids, toddlers, or young adults, it's even nine to 10 hours. Those of you who have a kid, you know, that night the kid did not sleep for more than eight or nine hours the next day, you will know that. So that's very simple when we don't sleep enough, we have immediate signs that something went wrong because when we sleep, that's when the combined enough sleep and circadian rhythm, they help detoxify our brand, literally detoxify, because many of the toxins, many of the breakdown products, byproducts that are not necessary for our brand actually drained out during our sleep. The second thing that happens is during sleep our brain cells or neurons, strengthen the connection between them. And then the question is why this is important. When our brain cells talk to each other and strengthen the connection, then our brain can take in the information correctly process it correctly, and also spit out the reaction correctly. So the reason why the kid becomes cranky is cannot process the information coming in correctly or cannot process the information that's given. And instead of smiling, that's, I think out and the same thing happens to all of us. In fact, if we go back to a very simple thing that almost every adult experiences which is conflict between couples between loved ones, if you think carefully, you'll often find that at least one of the partners did not slip enough. I've been traveling a lot. And so it affects not only your brand, how but actually affects even your family. So that's the second

Claudia von Boeselager 17:59  
note anyone listening with relationship issues; just know that if you or your partner have slept enough, and if not, maybe park it until you're both well rested. So scientific proof

Dr. Satchin Panda 18:11  
So my rule of thumb is I never argue with my wife after 11 pm At night because I know that this is the time when my brand is loaded with not branded, and I'll be making the most of what is the emotional means it is because my brain is not processing in politics and so you kind of have a

Claudia von Boeselager 18:36  
better time.

Dr. Satchin Panda 18:37  
Exactly. And if and we also know that if we haven't slept enough if I'm coming back after long travel and all that stuff, I'm also it is because so this is a very telltale sign that you want to see whether you're the security and the disruption just so this is what second is. And these days, we have a lot of light, and when you are exposed to a lot of light in the evening hours. So we have two problems one is too much light in the evening. So a lot of light in the evening. And these days we even go out and buy those very brightly lit LED lights because we want to feel more a lot in the evening. Because everybody's coming back home very tired. And they just were still after coming home. We have to enjoy the evening time because life after sunset is very different from life before sunset, life before sunset or life before the evening is all about. An average person who is doing a day job is all about working. Making enough earnings so that the person can enjoy life after the evening is very different. We want to socialize we want to say our thoughts, we want to entertain ourselves we want to care for each other. Notice share a meal. And we want to feel energized to do that. And then we turn on all the lights via energize to do all of this, or watch TV. And then the problem is that bright light can suppress many nightly hormones, including melatonin, that actually help us to sleep. So, and that way, we have another circadian rhythm disruption if you see that you cannot easily fall asleep. Even though you're tired, even though you're tired, your hormones and your melatonin are not high enough. It's not telling your brain that, hey, it's time to sleep, rather than it's actually during you may be tired, it's okay. But I don't see any sign that night has arrived, and you can sleep, so that conflict happens. So there are a lot of people that say I'm tired, but I cannot sleep. That's another sign that your circadian rhythm disruption has happened.

Claudia von Boeselager 20:57  
Can I ask a question about the interrupt? Because you've done work around blue light and how it affects them in the retina? And I'd love to just dig into that for people to understand exactly. And the differences also between that blue light junk light and then like warmer tone light, like, is there an implication or a big contrast between them? Like, is there a good light versus the blue light, which we know is the junk light, but can you just break down the science a little bit, like what's happening, that the light is affecting melatonin production?

Dr. Satchin Panda 21:29  
Yeah, so this is where I would also bring up another thing that light is not good or junk the mistiming of light makes it good or bad. Okay, so people always say blue light is junk light like I said, but it's actually the evening. Excessive blue light is what disrupts our circadian rhythm. So, coming back to it, it's good that you pointed out this very important discovery from 22 years ago. Let's step back and then talk about light. So if we think carefully, if you're not living right at the equator, for example, you are in London. And if you look up now, at your sunrise and sunset time, you will see that the sunrise to sunrise time is not exactly 24 hours because of the tilt of the plane of our planet and the rotation. So that's why it's not exactly 24 hours. So that means every day, our circadian rhythm, my sleep-wake cycle, if you're not experimenting in the modern world, it's different though. But our ancestors had to adjust their circadian rhythm every single day, because it's not critical to ours, the sun, depending on whether it's summer to winter or winter to summer transition, either the sun comes up slightly later or earlier. So then how does this sunlight or daylight signal get into our clock? And for almost 35 years, starting from 1920s, scientists knew that all the light information to our clock circadian clock goes exclusively through the retina, at least for humans and mice, not for birds and other animals. But humans and mice and rats, all light information that is required to reset our sleep-wake cycle clock or circadian rhythm plot goes through retina but carries a twist. There are many animals and there are many humans who are blind because of some genetic disease or something that happened they are due to as they they're blind, they cannot see anything, they cannot read anything and everything is dark for them. But still, they could reset that security and just like normal people, and throws this conundrum you need the eye? Why do people leave that then did they die because there are many, many people who went to war the last word the eyes have they had cancer and both the eyes eyes are completely remote, and they cannot reset their clock to this day night cycle. So the that in 2001, three different labs including I was the lead the first author of that paper, we discovered that there is a blue light sensing protein called melanopsin. And this melanopsin protein sensors blue spectrum of light. And you might say, well, I don't see any blue light. But you we all know that this daylight has all these seven colours. So that's why we have the rainbow colours. So daylight is actually the richest source of blue light, there is nothing there is nothing that we have designed so far that any other light source that can exceed what did they light or sunlight can produce in terms of blue light. So this blue light sensing protein senses the light Do some light and used to reset our clock every morning. And in the evening, although our ancestors light it off some fire, then grill something or bake something whatever the day there are some light coming out of this Amber fire, that fire light was mostly orange colour because there is no, there is not much blue light there. And this melanopsin protein was not sensitive to blue light, sorry, to orange light. So that's why, even though there was orange light, even though people could actually see each other, sing and dance or talk stories to each other, that like was not very effective. And as a result, now, by nine or 10 o'clock, these people would get tired and go to sleep. And in fact, even these days, some of my very heroic scientific colleagues who have travelled to very few parts of the world where there is no electricity now. And only you can imagine that it's not easy to access those places, they go there and then study people who have no access to light, electrical lighting, they have fire light. And literally, they switch plates between 930 and 10 o'clock, all of them would go to sleep. And then exactly at dawn, there is Twilight, they'll all wake up just like there was a alarm clock went all over the villas they all wake up and become. So that used to happen. So now with the new bright LED lights that we have indoor, these LED light, particularly the white blue in this LED. If you have any confusion, just walk to any grocery store or drugstore, anywhere in the world, there are low and risk LEDs,

Claudia von Boeselager 26:51  
it's not a very flattering light either.

Dr. Satchin Panda 26:56  
And that's the light that you want to avoid. Because of course in business, for example, you don't want the pharmacist in the pharmacy to fall asleep and mechanistic. So that's why it's okay to have that bright light in policies and drugs turn. Same thing when you go to a grocery store. Two things happen, they want you to be awake and grab as many items as possible. It's good for business and ultimately checkout. So the point is you don't need that kind of light in your in your bedroom in your living room. So that's why you have to pay attention. And the good news is there are two solutions. One is instead of light switches, you can instal dimmers light dimmer, so that you can dim down the light irrespective of what light you have, you can just dim them down because another property of this melanopsin protein on the lamps and blue light sensing sensor is it cannot actually sense too much of dim light. What is dim light. For example, if your old school if you had access to the 40 watt light ball and equivalent will base of 40 watt equivalent LED light. And if that light is kind of on the ceiling, in a big room, three metre by three metre or 12 feet by 12. Yeah, something like 10 feet by 10 feet, something like that. So then that 40 watt light bulb in a small pond in that kind of room will give you what is considered the manuf light so that they don't activate your melanopsin as much as, but there is a caveat. But if you're sitting in there, and then you have your iPad, if you have your tablet or PC or laptop with full glare that will also disrupt your circadian rhythm. So that's why it becomes important to kind of pay attention to lighting. So rule number one, don't put too much led blue LED light in your living room or bedroom. And if you do, because I will tell you why you see sometimes, then instead of flipping a light switch the old style light switch, put a dimmer so that in the evening you can actually dim them down. Or if you have more money, you can actually have a programmable timer that will dim down the light. So that's about control purchasing the light and controlling it. Second is we get a lot of light exposure from rectangular pieces of glowing objects, whether it's your phone, whether it's a laptop, or there's your tablet, and fortunately all of them have inbuilt feature to what is called Night saved feature. So you can turn that on. So depending on what is your preference, maybe eight o'clock or nine o'clock they will all dim down or change their spectra to orange coloured light. So that's half of the story or how you should manage light in the evening. During daytime the story is very different because for most of us We spend most of our time in dimly lit classrooms for high school, college students or in offices. And only when you are a top notch executive, you'll get that corner office access to a large window. But for most of most people that actually stuck in a interior office with very little access to Windows, even though you have a bright light, you think it's bright enough, that light in most cases is not bright enough to fully activate your melanopsin, a blue light sensor during daytime, so that you feel more a lot, you can actually take over, you're happier. So that's why during daytime, you need to be exposed to at least 30 minutes of daylight. When I said they like don't have to go out and look for the sun and upstairs unless even in London, in a cloudy day, you get sufficient, you get five to 10,000, lots of light, and five to 10,000. Lux is a whole lot more because in the evening, if you walk into a drugstore or grocery store, you are getting only 1000 blocks of light. So a cloudy day in London is at least five to 10 times brighter than your bright drugstore that you can.

Claudia von Boeselager 31:25  
If it's cloudy, though, do you need to increase the time. So say it's a sunny day you want to aim for is it just 30 minutes a day to get that exposure. And then ideally in the morning, would you say or if it's cloudy, does it need to be an hour or two hours to be equivalent, it kind of reaches saturation around

Dr. Satchin Panda 31:41  
four to 5000 blocks. So it doesn't matter. But what we feel is there is some more benefit of even super bright light, like for example, a day like with with full sun in London will be 100 to 200,000 rocks. And we know that there are now they're also incredibly light coming. And then there is UV light, so we have to be careful about. But there are also new violet lights. And there are many new light sensors that have been discovered these days. Which suggests that there are other functions of light that may be going through your skin, and not directly related to security under them. But for other reasons. Like for example, vitamin D, if you want to avoid taking a vitamin d3 pill, then, of course you have to be exposed to more like, but when it comes to just regular people who are not depressed, and they want to get some enough light, the morning light is better because our executive function is much better in the first half of the day. We're already programmed to be more happier a lot and have ability to take on complex tasks. And on top of that, if you actually get this blue light spike, then that helps to have that high performance for the first half of the day. When it comes to people who are feeling low depressed, whether they're on medication or not, it doesn't matter. Any bright light during the day is extremely important for their brand. And this is something that we always have to keep in mind means we always say that well, there are so many kids who are these days going through depression, almost one and depending on the stats where how you look at it, one in three colours going female students and one in four colours going male students may be experiencing depression. And we talk about lots of things about self support and other stuff. We never talked about one thing that dorms lighted enough, they're spending too much time in front of the computer so that they're actually not going out to a. So when the issue of mental health comes in, I always tell if you want to care for somebody, just take them out for a walk in a during the day doesn't matter whether there is bright light, dim light, cloudy day or whatever. Just take them out for a walk, they will get your company they will get some physical activity and they'll get light. And light is the best daylight is the best antidepressant. It's plentiful and free. You just have to step outside. But when you're depressed, you may not feel the urge to go outside and that's why your best service for somebody you care for who is depressed is to take them out for a walk during the day. So this is a story about more lie down there. And for depression. Most researchers agree that you have to get that daylight for at least an hour 30 minutes may not cut it an hour is better and if it cannot go out, then at least a few or living with someone who is going through the prison or filling law, at least open all the curtains and the room. And if you have even extra light, as I said, LED light, this is where the LED light or the bright light comes into play. This should be in a brightly lit room with large windows and lots of lights will be coming in. That will help a lot.

Claudia von Boeselager 35:24  
That's powerful advice, especially coming into the pandemic. And obviously, where people were spending a lot of time indoors. Man, I remember reading research that the average American and the average UK citizen spends up to 90% of their days indoors. So already there that's, you know, just getting outside more often, ideally, moving ideally in nature, if possible, we'll just totally shift so many different balances and support the circadian rhythm as well. So that's really great advice. Thank you for sharing that. Regarding sleep, you were saying, you know, timing is so important. So there's the quantity. But then the question is some people are like, Well, I'm a night owl, I work really well in the evening, or you know, I wake up at 4am Like people have different rhythms, if you will. So how does one understand circadian rhythms when you know, there's a couple one goes to bed early one because a bed late and they they sort of function that way? Like how can one think about optimizing circadian rhythms for sleep with different sleep schedules? So

Dr. Satchin Panda 36:26  
here's a tricky question because everybody wants to feel special. Everybody wants to feel unique. But now let's, let's dial back and go back to my okay. Yeah, researchers who went to study this ancestral population who are living without light, and the question is very simple. They're also night owls and Oliver's among this population, the answer is no. So that is the genetic contribution or how our genes are designed to make us late at night owl early bird is still there, there are undeniably there are some people who really cannot stay awake after says 8pm If the sunset is happening at six, for example. And there are clearly some people who cannot go to bed they don't feel sleepy, even up to one or two. So those people exist. But they're not as frequently found, as we often think they are. One in few hundreds or sometimes one in few 1000. So now the question is, well, why we always celebrate ascribe some of, particularly night owls, many people say that they're night owls, they just function much better in the evening. And they're more creative, they feel more energetic in the second half of the day, etc. We don't have a clear, objective way to measure that. What we have seen, this is where Anette data and personal experience also comes in. I was like, I used to go to bed at three o'clock in the morning. I used to work in the lab and feel really energetic or come back around one or two and that still relax a little bit or catch up on some lab like email or phone calls. And then I start well, I was having five or six Diet Coke throughout the day. Know that the caffeine, which I knew that the caffeine affects a lot, so then I took care share my caffeine and light exposure. When I do even this is for one month, I said okay, so I'll not go on caffeine. I'm completely out of caffeine. And I feel like I haven't slept for a month or two, the first two or three days. Of course, you have to be hydrated enough to avoid the caffeine withdrawal headache. And when I do that, there is no way I can stay awake beyond 10 o'clock at night, I become that one of those ancestral person who used to go to sleep after the pilot died at 10 o'clock. And in my own family, I've seen my mom always complain that he cannot sleep before 11 minutes out, see, see lives in India, so called sometimes and I'm like, Oh, I'm wide awake. And then now she's visiting me for three to four months. And now idealise that she has afternoon tea around four or 5pm. And then I said no, you can have only tea up to 12 Noon. Of course the past one or two days is like complaining, hey, my son is depriving me of the simple joy of life and how can you do that I raised

Claudia von Boeselager 39:52  
let's try this experiment.

Dr. Satchin Panda 39:57  
It went on like three four weeks. Of course you didn't tell me thing but the other day I was listening to her and then she was giving advice to her sister back in India that, hey, you know, you stop drinking tea and I have no problem go to bed around 10 o'clock. So, this is some example that I now if you think about it now all the listeners who are thinking that diehard nite owl, very few attention one is wanted your last sip of coffee, tea. And in our diet coke, anything that has caffeine. The problem is in these days are many drinks many food where we don't recognise that there is caffeine or There is for example, dark chocolate also has elements that can keep you awake. And there are also some personal interaction. Like for example, I'm extremely sensitive to hot chocolate means if I have hot chocolate, even for five sips and leave it in for some reason I cannot sleep.

Claudia von Boeselager 41:00  
But if it does sugar, the sugar in it or

Dr. Satchin Panda 41:04  
not the soda so when sometimes I and I have friends who bring this German hot chocolate that has no cigars is very good to drain. And I know that I had to drink that anyway. So there are some food interaction that also affects our sleep. And then the third, another one is light, we don't pay attention to light, a lot of people are exposed to light in the evening. And then the last part is sleep. So for example, those who are night owls, they're already into a spiral because they go to sleep very late. And for many of them, they still starts at eight or nine in the morning because they have a day job. So they're sleep deprived for the first half of the day, they're struggling, they're drinking coffee to keep them awake. And then towards late afternoon under sleep pressure is reduced. And they feel that they're more energetic. It's not because their circadian clock is like that because of their sleep deprivation. So if you're really fighting off to stay awake, and the first half of the day, because you're trying a lot of copy and other stuff, it's likely that you're not sleeping enough, and that's putting it in a spiral. And then in the evening, you're feeling more energetic. And so that goes on. So that's why I always say that before you blame your genes, your parents, it's almost like you know, if somebody is overweight, we're not going to tell well, your genes are like that. The first thing we say is how did you pay attention to what you eat, how much you eat. And then same thing here. Just pay attention to your light, and caffeine and tech.

Claudia von Boeselager 42:46  
So night I was listening if you want to do a test like Dr. Mother, quit the caffeine. So no caffeine after 12 o'clock. I used to say two o'clock. Yeah. works. Okay. And then the watching the light from sunset, right? So the question is always, for some people like what time now obviously in northern regions in summer months, it's can be late until 11 o'clock at night. So it's creating a darker environment to allow for the melatonin production and the wind down to get towards towards bed as well. But I'd love to hear back if anyone's a night owl and they tried this experiment how it goes. We can add to the list of examples together with

Dr. Satchin Panda 43:30  
Yeah, I mean, there are so much about light dark cycle that we don't pay too much attention. Another very powerful example which is not with doesn't apply to most of us. But some very extremely vulnerable individuals is neonatal ICU years. Those babies were born before the full term, we know that they are kept in special ICU Intensive Care Unit like setups neonatal ICU, they have been hooked up to many tools, many sensors

Claudia von Boeselager 44:04  
and an incubator normally ran in the incubator

Dr. Satchin Panda 44:07  
because they cannot control their own body temperature. And those neonatal ICU is always lighted. So they're continuously light. And we know that their circadian rhythm may not be as apparent as adults because just like every other baby they're sleeping, waking up a little bit sleeping and waking up, but they do have a strong security and internal clock. And that clock is still sensitive to light even though the eyelid is closed. Just imagine even if your eyelid is closed, if there is sunlight coming through your room, you will be sensing so similarly this babies can also sense it. So here's a very simple experiment done in Mexico City where this researcher wanted to know what happens if we simulate some bright light and dim light not even dark. In this experiment where there are nearly 60 Premature babies randomised to two different groups, one group standard of care, continuous lighting, the other group got around 250 300 loss, which is a normal hospital room during daytime. And then from 7pm to 7am, the gently covered only half of that incubator kind of setting. So that at the eye level of this baby, there was only 2025 locks applied very dim light. Surprisingly, this premise premature babies were exposed to light dark simulation, they were released from hospital on an average 13 days earlier. Wow, than previous work. I'm concerned like, there's not even a single drug in this entire world that can have this much impact. The reason why they were released 13 days early is because the growth accelerated. They said they've met all the milestone growth and the doctors felt they are now okay, they can control their body temperature, they can be just like normal babies. And this is so powerful. There is not a single drug anywhere in the world that's in clinical trial or anywhere that will actually accelerate the growth of premature babies this much. So as the power of light and

Claudia von Boeselager 46:28  
darkness. That's really incredible. Is this now standard practice and I hope you're going to say yes, in all out of

Dr. Satchin Panda 46:35  
Mexico City. Yes.

Claudia von Boeselager 46:37  
You need to share this information, please. Um, you know, you can just imagine for the parents how distressing it is, as well. So to get a baby a newborn baby home quicker than that with 13 days. That's incredible. Wow.

Dr. Satchin Panda 46:50  
Yeah, because in the US, right now, on average, one in 10. live birth is actually premature baby one. And so in the US 3.8 million babies are born. So that means 380,000 babies are born premature. And I guess I don't know about the UK and EU, it may be very similar one in 10 to one and 12 something in that bowl. So that means almost every listener might know someone might have heard it premature baby,

Claudia von Boeselager 47:23  
feel free to share with people listening with doctors and hospitals. And some of them listen to this as well. What a game changer. And it's not medication. And that's what I love about your work is that it's not a prescription of have to take 100 supplements, and you have to do this. These are all free things that are naturally available. And it's actually going back to the way the body was developed for hundreds of 1000s of years. So it's really beautiful. I have one question with the detoxification at night, is there certain standard cycles? That happens? So I think with melatonin production, there's certain waves right when it when it happens as well and detoxification? So is there a chance if someone goes to bed too late that they miss one of the detoxification cycles? Can you talk a bit about that? Yeah. So

Dr. Satchin Panda 48:08  
this is a really groundbreaking discovery that happened in last 10 years. A scientist Michael Nadeau guard who made this discovery that in nighttime, when we sleep, there's this thing called Blind PROTECT system just like lymphatic system in the periphery. So this glymphatic system in the brain actually takes out the garbage is. And as you can imagine, this is a very difficult experiment to do. Because people have to come to the clinic data slave, they have to be connected with different tools so that it's not only you're not actually sampling blood, because blood sampling is laughably easy, because people can sleep, you can still put a line and draw some blood, but it's even more complicated than Spinal Tap. Like for example, almost every woman who has had an epidural, they know that is done. So it's similar, slightly more complicated, actually. So you're supposed to

Claudia von Boeselager 49:15  
stay asleep, right? I mean,

Dr. Satchin Panda 49:17  
while you were asleep. That's why

Claudia von Boeselager 49:22  
we've medication without medication without.

Dr. Satchin Panda 49:25  
So that's why it's so difficult to know whether there are certain stages of sleep where this thing happens. The bottom line is it is a very slow process and it happens throughout our sleep. So it doesn't matter. Just sleep like at least six and a half to seven and a half hours. This has a huge implication and the this has become the biggest discovery in sleep field in the last 30 years, I would say and we're still Trying to figure out how this is triggered whether there are other hormones or processes that are that are involved in this. But you brought up another important point that is, there are many hormones that also go up during sleep. And one of them is growth hormone. And you might think that, okay, so adults, we're not growing, why do we care about growth hormone, actually, we are kind of growing because your body composition, like for example, all the cells I have today, will not be with me 1010 days down the road, particularly my gut lining will be completely new, just like this neck with a completely new skin. Each of us is putting a new gut lining in every 10 to 15 days. So that means we are shedding all the old cells and putting new cells, the same thing happens to our skin to our cornea, the lining of our eye. Almost every cell that is exposed to outside or expert to our food and other things inside, they are damaged and recycle. And the growth hormone plays a very important part in that rejuvenation still. And that happens only when we add that there is a spike in growth hormone, it just spikes. big spike in the first couple of hours after we go to sleep. So then the point is, well, if you go to if you delay your sleep time, then what happens suppose say I go to bed every day at 10 o'clock, my circadian clock knows around 1030 or 11, it cranks up growth hormone for the next couple of hours and then it goes down. What happens if I go to bed at one o'clock one day. So two things happen. One is the circadian clock will practically Kindle with Chinese blueprints, growth hormone, maybe when I'm supposed to sleep around 10:30pm. And then after I go to bed, again, there'll be another spike. So that's kind of a sleep driven, small speck. But that will not be as big as my first bike. So the bottom line is yes, you will get some growth or manipul delay your slave. But it is not as good as if you stick to the right schedule every single day. So that's why one point about timing and duration of sleep is maintain relatively similar going to bed time. So if you're going to bed at 10 o'clock, yes, go to bed plus or minus 30 minutes or so. And you will get all the benefits

Claudia von Boeselager 52:45  
at the same time and 30 minutes plus or minus and getting up at the same time, would you say

Dr. Satchin Panda 52:52  
around the same time will also help because if you're getting up without an alarm clock, that means your circadian clock is actually waking you up. So growth hormone, the rule of thumb is after we go to bed in the first two hours, it takes melatonin on the other hand begins to rise two to three hours before we go to bed. So it begins slow ramp up. And then it reaches its peak, maybe four to five hours before we wake up. So literally in the middle of our sleep, it reaches its peak and then it slowly goes down. We'll go to we'll talk about melatonin when we talk about food.

Claudia von Boeselager 53:30  
And I know from speaking with some male friends that say that, you know they waking up at sort of between two and 4am. And they're like completely awake. What's happening there.

Dr. Satchin Panda 53:40  
Yeah, so there are two things that may be happening. One is the sleep is not deep enough. Okay. Second is maybe they're going to bed too early, which is not happening, which most likely is not the case again, which is not likely to occur. So what we have, so what happens is, we know that we go through this rem and non REM sleep cycle. And then in REM sleep. This is where the rapid eye movement where eyes are moving, and this is maybe we're dreaming. And many of us can learn that when we usually wake up from a dream. So that means our REM sleep. This is when our sleep is very shallow and we are more likely to wake up. And those of us who complain that we cannot we wake up around three or four usually happens around three or four. It's not within the first three or four hours of going to bed. It's after four hours of going to bed because by that time our sleep is getting shallower and shallower. And then something internal or something external can trigger us to wake up and so it led to something that we call arousal threshold. What is your threshold that some disturbance will wake us up? So now, monitoring about arousal threshold, the only thing that we think of is okay, so there is some noise from outside that will wake us up. But actually, there are many things inside our body that will also break this arousal threshold. And we can wake up. Best example is, for example, people who have to go to the use the bathroom, they press on the bladder, or the colon is telling them a wake up, now you will use the bathroom. Same thing, if then the bed is warm enough, then you'll wake up, you'll feel like okay, so the bed is too warm. So what happens, we still don't understand why our arousal threshold goes down as we is, for example, a mom and the baby maybe sleeping in the same bed, that mom might put the hand on the baby doesn't care, baby kicks, the mom and mom wakes up. So that's the best example of arousal threshold is pretty high for the baby. So see her he doesn't wake up, whereas the mom wakes up with his gentle couple of kicks. And then now the grandma will wake up even baby just turns on the other side of the bed because our arousal transport goes down it is. So now how do we manage that. So what we have seen with food timing, people who are bored for for three to four hours before going to bed, so there is no food, there is no calorie, maybe only water, sparkling water, simple water, you can sell them on water. We haven't done the experiment. But the bottom line is if there is no calorie then somehow that helps to increase the arousal threshold, what we think might be happening or reduce the internal problem that happens in our body. So for example, you may not your body may not wake you up, because maybe your bowel movement or your blood pressure will not build up. So we we haven't done why exactly this happens. But what we have seen in many people not all avoiding food for three to four hours before going to bed actually helps them to go through the entire night or get six to seven hours of sleep without waking up after four hours and crossing an

Claudia von Boeselager 57:27  
interesting is there any correlation with insulin levels in the blood,

Dr. Satchin Panda 57:31  
we haven't done any of that it will be interesting because I know that there are a lot of people who are not type two diabetic or pre diabetic, they're completely healthy, but they're still wake up. For me, what I have seen is when I'm in new hotel room with new pair, sometimes sudden hotel brands, their beds actually warm up. So I wake up around four o'clock, and a warm bed. My rule of thumb is when I'm booking a hotel room, I always ask for two queen beds so that I just got a

Claudia von Boeselager 58:09  
few people that travel a lot. That's a great tip. Thank you. There's obviously mattress cooling devices. carry all these devices. Exactly. Okay, wonderful. Thank you for clarifying that. Let's look at nutrition and time-restricted eating aka intermittent fasting. This has gotten a lot of publicity loaded. A lot of people have tried different versions of it. But before we sort of dig in, can you explain sort of generally what the concept is around time restricted eating and why it's so important

Dr. Satchin Panda 58:47  
so far as a Manson we believe for a long time, we still believe that the light is the biggest time giver in training stimulus that's in trance synchronises, our internal clock with the outside world. And light goes on through the eyes. That's why light is so important. But over the last 23 years starting from 2000 people did some simple experiment saying well if light is important, what is about food, there is an is in our liver garden, all these digestive and other metabolic decisions. There are many genes, many enzymes that are involved in digesting food absorbing nutrition, converting that nutrition to energy or converting that nutrition to various chemicals that are essential for our body. All of these things actually turn on and off at different times. So that means there is a CKD and rhythm to that. So that means in the morning when you wake up the clock in our pancreas, you Stand up so that for the first half of the day, we can actually eat carbohydrates. Without too much spiking hours, glucose, glucose, blood, glucose will come down. So all these things happen. So then the curiosity was Well, at this all driven by the brain clock that's tied to the light, or there is some connection with the food. And many labs, including my lab, we figured out that no actually for when animals ate because all these experiments had to be done first in animals, lab rats and lab mice. When mice eat, particularly after several hours of fasting is a very powerful timing cue to tell all this benefit, we call it petrol organ, because they're outside the brand. Got liver, etc. Heart, they actually track when there's mice set, and the clock, the timing, the counting of time, you can say kind of starts from there. So that means suppose that we feed mice every day at 6pm. Because mice, nocturnal, they're night active that prefer to eat at night. So everyday, if we feed mice at 6pm, then the body's metabolism circadian clock, everything is tuned so that studying from say 4pm onwards, their digestive juice, and everything will accumulate. And then the body is primed to digest that for six o'clock 6pm We give for them there, everything is ready so that it can process that food pretty well. And if we give that food for example, one day, instead of giving at 6pm, if we go to set 10pm At night, then all these preparations have happened, but then the food didn't show up. And it's almost like inviting somebody for dinner, you have prepared everything. No show the guest is two hours late. What happens if food is stale. And you're not that excited, you still entertain your guests. But it's not as good as you expected. The same thing happens when you miss time you have been you have been so habituated, your clock is so habituated to digesting assimilating foods so well. And when the food doesn't appear on time is delayed than the digest and all these processes happen, but not as efficiently as it could have been, the same thing might happen. If the four sides of earlier it may not get digested, it will just sit there for a few hours before it's well digested. So that's the that's what we found that the when food appears, and if the food appears at the same time, every single day, or most of the days, then that triggers all the circadian rhythms so that the body is prepared to digest that food. So now so this is one concept, the second concept is okay, so the food has to be eaten after breaking fast, how long that fasts should be right? So this is where all the arguments what is fasting? How long is the past. So now you got to go back and think of not in mice Because mice digest food much faster than we do. But in humans, for example. So if I finished my dinner at 6pm, and the good healthy dinner or whatever I ate at 6pm My mouth stop eating. So from my from my mouth, the fasting might have started actually went to my stomach. Sure, yeah. And then it will stay in my stomach being digested for the next five hours. And so for the next five hours, my stomach is not getting rest, it's actually not fasting is digesting poor and then after five hours it will live stomach and we'll go to the test time where the nutrition objectionable. So that means from 6pm till 11pm Although I'm not eating, my stomach still has food and is still absorbing food, it's not fasting. And then if we think about our gut lining and the stomach lining has to be repaired. So suppose I went to bed at 10 o'clock 11 o'clock, my growth hormone will spike around midnight. And that's when it will tell the repair crew to come and that is the layer of repair the gut lining. So that's when all the repair is happening. And that process is not just instantaneous. Those of you who have seen how they you know, highways repair, it takes time. So you can imagine that that's an six to seven hours when this happens. So now you can imagine that, okay, so five hours, although my mouth started fasting, My God is not fasting. So there is still five hours of digestion. And then you are six to seven hours, at least seven, seven hours when the repair has to happen, but I'm saying that the stomach stop its role, but the small intestine and large intestine, they still continue observing so there is still work going on. So that's why the actual fasting being withdrawn from actively eating food when it is at least 12 hours, then we know that okay, so the body actually went through the daily cycle of absorbing nutrition, repairing the gastrointestinal tract. And then for the preparation for the next round a full, as I said, the, again, all the digestive juice have to be prepared and ready. So that's another few hours. So similar. So if you are the software humans at least 13 to 14 hours of overnight fast is what is needed for this cycle to repeat again, in a healthy way. Because you can eat, nobody's stopping you from eating.

And also you cannot repair. So so this is how the concept of time restricted eating can because we thought, it's when it comes to nutrition, people always thought with very strong foundation of scientific foundation that the number of calories we eat is important. Of course, that is important because I just can't go and eat 4000 kilocalories and then say why I'm getting fat. I know. Number of calories do matter. And second is the quality of nutrition also matters. I can't just go and eat ice cream only and then say complain why my blood sugar is going up. So those two things matter. But the third thing that we found is timing is very important because particularly how long we passed. And when we started this concept because it started in my lab 12 years ago in 2012. And I remember struggling with the title of the manuscript. Because this experiment was done in mice, the experiment was very simple. We took two groups of mice identical mice same as same genders. Born to the same similar parents in the same room had the same gut microbiome had the same food and the same number of calories every day. The only differentials the first group add whatever they wanted, there is no barrier. And the second group, they were allowed to eat only for eight hours in the first experiment. And within eight hours, they entered the same number of calories as the first group. So there is no difference in number of calories, no difference in quality of food. Both groups got actually high fat, high sucrose, really unhealthy food. And were surprised the second group which time restricted because our eating only for eight hours, the consistent eight hours, we didn't move that eight hours. They're completely prevented from obesity, diabetes, liver disease, heart disease, and they had way much more endurance, there was a surprising fact that it's not under fasting and they're feeling really crappy about life, they were actually more active, they're full of energy. They could stay on the treadmill twice longer than the minds that limiter. So then we thought okay, so what should we what should the title of the manuscript should be and then we said, time restricted eating because we're not changing quality of calories, not changing the quantity of calories. We're just changing the time we were restricting the time no calorie restriction. And we did not use the word fast because there are a lot of people who actually need to fast but then they don't want to fast because here's starvation they hear fast is a very bad four letter F word for them. So they really don't so that's one aspect and then the other aspect is well, we fasting is very ill defined because for example, sometimes people ask me Hey, do you fast I said yes, I passed between meals.

Claudia von Boeselager 1:09:33  
Whenever I'm not eating, I'm fasting. Yeah, exactly.

Dr. Satchin Panda 1:09:36  
So it's very difficult to define that. So that's why we said okay, so we'll just do this time machine eating and I just said this began, this fell under the umbrella term what is intermittent fasting because before this experiment, intermittent fasting essentially meant few things. One, you can fast every other day, which is called every other day feeding and scientific literature. It Can it could also mean fasting for two days in a week or one day in a week. It also meant reducing calories only for five or six days in a month or two months. And when this type is eating Canada's kind of mouthful, so then people said this. So these days when you say intermittent fasting, most people will think, yes, we are doing eight hours of eating 14 hours, 16 hours of fasting. So we have done this experiment in many different ways. Coming back to your other question related question different forms of intermittent fasting. In mice, we can do, we cannot go below eight hours, because when we go below eight hours, then mice eat less. And we know that reducing calories, calorie restriction has many benefit. So we cannot figure out whether it's the benefits are due to reducing calories, or eating within a short window. So these experiments are not doable in mice. In humans, people have done these experiments, they ask people to eat within four hours or six hours. And as expected, they also reduced that total caloric intake, they eat less. And of course, there is also benefit. But we cannot clearly say whether the benefit is from reducing calorie eating within this very short period, four hours or six hours. There's some studies where it's very well controlled, healthy human volunteers, either as to eat everything within 12 hours, that's the control, or six hours is very sort window. But no, this is an experiment, we are not asking people to do this every single day. And in those experiments, which came out of Courtney Peterson's group, University, who is at University of Alabama, Birmingham. Now, they found that even though the second group that within six hours at the same number of calories, they're still benefited, in many different ways, including improvement in blood sugar control, blood pressure control, although these people are not too sick to begin with, so they were a little overweight, but not incremental

Claudia von Boeselager 1:12:12  
benefits. Yeah,

Dr. Satchin Panda 1:12:14  
so the benefits are there. So that's why we said the time restricted eating is still a valid approach to do a nutrition one can combine it with counting calories, and paying attention to quality of nutritional

Claudia von Boeselager 1:12:31  
quality. Yeah, eating whole foods. And because I'm not I'm not a big carry, counting fan, but I think it's quality of like Whole Foods and sort of the peripheral of the supermarket is generally a good rule of thumb is

Dr. Satchin Panda 1:12:47  
I guess the biggest challenge in nutrition, there are two big challenges. One is a control for time, like, we almost think that our our body, our human body is like a machine or a car, people always give their similarity and innocence and cause they will run whatever time it is. And you can fill up your gas tank in a car anytime of the day doesn't matter. But we are not like that. The difference is you can drive your car whatever time you want, or whatever you do to it. But you have to take the car to the repairs after the mess inside the first tenant, somebody else has to service your car, whereas our human body is designed to service itself, because that's what happens with circadian rhythm, that period of fasting, that period of sleeping and aligning fasting with sleeping, that's the best repair mechanism and nothing can there is no repair stop. No, literally no, there is no drug there is no procedure in hospital that can actually substitute for that repair process. That's so valuable. So that's one aspect is we're not paying attention to timing of nutrition, we feel like we can eat anytime. And then the second thing is beyond CKD. And the the problem is we don't know how to prepare a meal. We don't know how to cook so then when we don't know how to cook then the quality of nutrition. We just depend on what is written on the food level and everything goes out. So with timeless eating what we're finding is very interesting in many studies, what people are finding if they're only told to eat within say eight hours or 10 hours most of our studies we involves 10 hours because what we found is for average people 10 hours is a good target. Of course there are some who really want to optimise into biohacking and other stuff. They can do six hours they can do eight hours. But for most people it's 10 out What do we find is when people go through 14 to 16 hours of fasting overnight, next day when they're eating? Typically, breakfast is the healthiest full meal of the day, a lot of us if we eat breakfast at home, because we have complete control over what we're eating, and how much waiting. So what we find is people eat a healthier breakfast. And since they eat a bigger breakfast, and breakfast doesn't mean morning, we'll have 2014 our suppliers to Sunday, then they don't snack until lunch. So the number of snacking also reduces and most of our snacks in modern days is really high sugary drinks. So that reduces so it improves food quality. And since the kitchen closes at the stop eating at six, seven or eight o'clock, if you think about it, almost all of our addiction, whether it's alcohol, or whether any sweet treat, what about bad food we are addicted to that happens typically late at night. So people reduce their alcohol intake. And this is we're finding in many different studies. And they also reduce the late night ice cream intake. And in fact, in my house, we have seen this since I used to be number of beer bottles. The wine bottles we used to go through before and after has dramatically changed. It's amazing. So so in a way timeless rating or intermittent fasting, all the people pay attention to timing, it indirectly improves their nutrition quality, and also reduces some characters.

Claudia von Boeselager 1:16:52  
And I'm curious, a few different points I want to touch on. What is the minimum time you would recommend? So is it that 14 hours that you were saying in order to have that cycle those 1314 hours? overnight? And then differences between men and women, particularly around hormones for for women? Yeah, so

Dr. Satchin Panda 1:17:11  
this is a tricky question. Because what I believe is anyone from 10 year old 200 year old can Clyst fast for 12 hours, whatever healthy on how the most listeners will think that hmm, I am already doing that. But actually, that's not true. When we objectively measured when people are eating where people like to log, every single thing that we're putting in their mouth heard everything from water to all calorie dense diet. And of course, we figured out which we discounted water and some black coffee. And what we found is when we go from consistency, like within 10 days, it really sticking to that 12 hours and not we found less than 10% of people consistently eat all that calories within that to a large window, less than 10%. We were surprised and these are not shipped to us, these are just regular people are staying home retire, etc. So that means at least once or twice a week, we are eating either very late at night, or we're waking up very early to go somewhere. For example, when I when I travel, I get up early, although I'm not eating when I go to the airport, I see 530 Or six o'clock in the morning, there's a long line in front of all this food places. So this is another example you're working on. So the point is, are you consistent within that and that's why I believe anyone from 10 year old 200 year old can answer it within 12 hours if they're healthy. It's almost like brushing your teeth every day, right? And then the question is, if you want to improve your health, then the question is how far away you are from optimal health. So for example, if all your blood pressure blood sugar, cholesterol are perfectly normal, you don't have any autoimmune disease. You don't have any joint problem, nothing mentally functional, you're sleeping six, seven hours. Yeah, and you're eating all healthy for them, no problem nothing whatsoever, then you can eat within set 10 hours. So occasionally you can go to 12 hours. It's not a big deal. And they might see that the question is what improvement I will say. Personally for example, I might target was to hit the age of 50 without being on any medication for cholesterol, sugar and blood pressure and I achieved that but then once in a while I would get acid reflux or heartburn and when I eat within 10 hours or 12 hours within that window, I don't have any heartburn acid reflux. So that means So I'm fully productive and not worrying about my, my gut health. And when I eat within this eight to 10 hours, then obviously, I'm also finishing my meal three to four hours before going to bed. So that means I used to wake up at four o'clock, just like you mentioned, and iced coffee in three to four hours before going to bed. I sleep continuously for six to seven hours, at least. And so this is another example where if you're healthy, you can still do it because it's good for your sleep. And then next day, you're feeling more energetic, and your executive function for the first half of the day goes up. Now coming to people who had blood pressure, blood sugar, or blood cholesterol, whether or not they're on medication or not, this is where it becomes a little tricky, because you don't want to fast too much. So for example, eight hours of eating 16 hours of fast, depending on your blood sugar, how it fluctuates, we cannot say. So this is where you have to consult with your doctor. But if it is blood pressure, or blood cholesterol, maybe eight to 10 hours of eating and rest fasting might help you. In fact, almost all timeless rating studies have shown improvement in blood pressure, whether the person was taking a blood pressure medication or not. And for cholesterol, it takes a little bit longer. And also diet quality has a huge impact on blood cholesterol. So this is where people have to control. Now when it comes to weight loss, because everybody wants to lose a little bit work, which is understandable, because 70 plus percent of people in the Western world and now even in many other countries, that person is increasing, have some extra weight. And this is where it becomes a little tricky. Because do you want to do six hours eating or eight hours eating? And then if you want to lose the weight that you want them to do you stick to it, and then how much weight you lose. So when I for example, a couple of weeks ago, I was in Chicago and I had a completely non work related convention, nothing I was not expecting anybody to come up and didn't recognise me. And then somebody came up to me and recognised me and said, Oh, I should thank you because I lost 55 pounds and all that stuff like 20 Plus kilos. And then there was another guy who can say, Oh, I also lost 14 pounds. And the first guy was telling the last day look, I lost 55. And yours is nothing. He said, Well, it depends on where you started.

Claudia von Boeselager 1:22:41  
It's all relative, exactly. related. So and then there was another

Dr. Satchin Panda 1:22:46  
third person who came and said, You know, I was doing everything. I'm already healthy. But I tried what you said before on one of your podcasts, and now I'm sleeping better. And that gives me a lot of energy in the first half. He's retired he's at now I'm involved in many non government organisation volunteer. So all these bring the joy of life because I'm more energetic. So here is an example of three different people with three completely different kinds of outcomes. One who says he lost a lot of weight, but it did not have any other problem. Although he was obese, he actually had surprisingly he had completely normal cholesterol on everything. The second one who lost 14 pounds, wasn't blood sugar medication, blood pressure medication, also on statin and now he's completely off of all three. And of course, he said that well, it helped me also pay attention to my nutrition because he's now eating better nutrition. And then the third one who is completely healthy is talking about his heart. So this is all males. So now coming back to women what I have seen that many women the benefit there is we haven't opened up a call my circadian clock. And we also have another commercial app now on time health that we can go to get on time pout my circadian. On my circadian clock. I get emails once in a while. And a common theme that was a most is many young women pre menopausal women. Don't try everything they're trying to eat within eight hours. They want to overdo it. So they say okay, I'll try six hours. And then they're eating very healthy for lots of leafy greens, solid and little bit of grammes. They're also running five miles a day. So guess what, they become a menarik because their negative energy balance, they're eating less than what the body actually needs. So they lose their hormone cycle and they become more cranky. And the complaint that is is not working for me. So this is where paying attention to your nutrition intake when you're doing time as you're eating and also whether you're exercising or not become simple. The second thing that I have seen the other better side of the story I have seen this from my high school teacher. She was also female as well. But what's it found C one C didn't see found that it met her cycle more regular shows exactly on 40 is and then Susan, oh, this is really interesting. And being a science teacher in high school, and so is also kind of it counsellor on official counsellor to many girls in the high school, she knew that many girls, they would miss a period of their late and they would become very anxious. And then she said, Okay, so why don't you try this? Let's try all of us try like 10 hours or 12 hours time acidity, and see what happens. And, surprisingly, see found that all of these girls became completely regular. They got their period in 38 plus or minus one two days. And that's when they contacted me. And actually I was invited to a nice dinner and her mom and she said, Look, this is what I found. Do you want to do a clinical like a human study? I said, Well, it'll be really difficult because her thing is these are minors and I agree that get handled, I shouldn't and and so, so this is some Annette data. Yeah. But I've also seen from other people who were trying to have children and they have some trouble that tried it with optimum nutrition, of course, and they could conceive, so then they would come to me email or sometimes even invited me.

Claudia von Boeselager 1:26:48  
This is why you're flying around the world.

Dr. Satchin Panda 1:26:51  
So for women, it's little bit tricky for now, postmenopausal women, we do see that it does reduce the risk for cancer and also many postmenopausal women who already have breast cancer. That chance of relapse reduces. And this is another experiment on another study done and neighbouring Institute, University of California, San Diego and the retrospective, we looked at women who had breast cancer. And were reporting self reporting 13 hours of overnight fast or not, they found that those who are fasting at least for 13 hours or more, they had reduced chance of breast cancer relapse. And that was significant. And now researchers have gone back and read on that experiment in laboratory animals where they wanted to see okay, so now because you know, in all human epidemiological studies, there are many variables. We don't know this is a smoking gun, but we don't know that we can connect it. So that's why, again, independent researchers not in my lab, they have gone back and tested and they find the same thing that those who fast in animal studies, if they passed over, sorry, consistently for 14 hours to 16 hours, then two things happen, they are less prone to getting cancer itself even though they were transplanted even though tumors are placed inside the mammary fab. And second, if the tumour is placed and the tumour doesn't grow as aggressively as in the animals that are fed randomly, that eat at any time. So, at least for postmenopausal women or pre-menopausal of breast at high risk for breast cancer risk. This is important that it reduces the risk for cancer. And we do see in our cancer survivors, it is a very big thing because in the US alone, there are 15 million people who have survived cancer and those who survived cancer. Because of the chemo and other treatment. They there is a lot of stress on their system. Many of them they struggle with their heart issues, some of them struggle with their glucose control and mood issue. And this is one thing that we would like to do because we want to see what the cancer survivors can stick to time to stay eating and can reduce the risk for heart disease and other diseases. The epidemiological studies show that yes, there are benefits, but there has to be intervention studies to put into practice.

Claudia von Boeselager 1:29:43  
This is really, really powerful. And I just want to summarise for women because I had been looking at this and I had tried. I was like those teenagers or young women you were mentioning like I've tried a whole SKU of different things as well. And depending on which phase of the month it was, I found that it was either energizing me or not. But I was literally reducing it down to sort of eating windows of six hours a day, sometimes even less at times, but sustaining that, but I think one major point you made is to look at two things. One is exercise. So I like to be active, I do a lot of exercise and movement during the day. So just to see if there's more exercise to make sure that the the healthy calories being consumed match that. So is that is that the point? So would you not see any risk in women doing, you know, six hour eating windows, but just ensuring that the calorie calorie glowed basically, that of healthy calories consumed is enough to match what is needed for the body to function on on a daily basis?

Dr. Satchin Panda 1:30:47  
It's certainly hard to make that call. And a big experiment. We really don't know what will happen because there is always a window. Yeah, no, we always think about the immediate impact, we don't think about the long-term impact, because particularly this is this is a problem that's very close to my heart, because we are doing now studies on what is called relative energy deficit in sports. Because nearly 42% of athletes, both male and female, they are an energy deficit, that means they're eating less than how much their body is spending. And in these cases, we this is so widespread, but still there is no animal model because he cannot sample the Florida organs, etc. So what we're doing that and we are finding that there is so much impact of this, there's so much adverse impact of relative energy deficit, because it compromises your bone health, and you may not see how it is compromised right now. Because even very strong, maybe you may not be hitting a wall or falling. But now five years or 10 years down the road, if you have really low bone mineral density, that can hit you there. Or if you have micro-fractures, that's one thing. And another thing we are also finding in animal models is that these threads affect different organs. In females, it affects the uterus and melts, it affects a lot the kidney and the impact is all over the place like in the brand, it affects the depression and anxiety centre of the brand. So that's why I'm really hesitant to say whether somebody should go eat within six hours. The problem is if you're eating within six hours, there is a good chance that one or two days in a week, you may not have the time or you may not have access to good nutrition to eat enough. And that's when you might lose your performance one or two days and you will blame and I know you're on the knife's edge. Okay, so a few mistakes. So that's why I'm very hesitant to say once a do six hours. Yeah, that's why eight to 10 hours is a good rule of thumb. Yeah.

Claudia von Boeselager 1:33:10  
Okay. No, but I think that's good. Because I'd love to ask you like, before we finish up for optimizing longevity and from the research you've done and what you've seen as well, what would be and I know people are different, etc. But sort of, for a general healthy person not taking medication or either or what would be the protocol that you would say, from

eating and sleep?

Dr. Satchin Panda 1:33:39  
Yeah, I would say there are six points we have to keep in mind. Number one, try to maintain a regular time to go to bed and be in bed for eight hours. So that you can get six to seven or seven half hours of sleep. Because when we sleep well then no brain and body actually repair itself much better. We reset, rejuvenated for the next day, were much better. So that's number one. Number two. After waking up, try to wait for at least an hour, ideally two hours before your first meal of the day, first calorie of the day, because that's when your sleep hormone. Melatonin is slowly coming down, and your stress hormone spikes reach his highest level within an hour of waking up and you don't want to eat on when your stress hormones are pretty high and your sleep hormone is still mildly elevated because your body cannot process nutrition pretty well. So that's number two. Number three is try to break the fat of breakfast at a consistent time. So it's breakfast is not The first meal that you eat right after waking up, it's actually the meal that you are eating after at least 12 to 14 hours of fasting. So try to eat the first meal at a consistent time. And then eat all of your rest of the calories within the next eight 910 Maximum 12 hours, never beyond 12 hours. And the last we'll serve, be you. So that's the number three. So let's start. Core one is try to step outside during the day, ideally the first half if you can, to get at least 30 minutes of daylight sunlight. If you cannot, it's okay you can get any time 30 minutes of daylight is good enough for the average person. And then the fifth one will be exercise those. Any exercise is better than no exercise, no doubt about that. But if you want to get the best out of your exercise and reduce the risk for injury, then afternoon exercise is much better than exercise late at night or early morning. Afternoon exercise has been shown to significantly reduce blood pressure reduce blood sugar than the same exercise in the morning. And since the body is warmer and the joints are more flexible, there is a reduced risk for injury. That's the afternoon exercise.

Claudia von Boeselager 1:36:32  
I thought first thing in the morning is beneficial in terms of blood flow to the brain for BDNF benefits.

Dr. Satchin Panda 1:36:38  
Well, the thing is, we if you look at the activity of the ancestral population, they are morning activity, they have a spike in afternoon activity; there is no doubt about that. But the morning activity is much higher than the average person's activity spike in the modern world. So what I say is in the morning, if you really want to be it, when people have plenty of time, at least go outside go for a walk for 10 or 15 minutes. And this is very important, particularly for college students and high school students. Because, you know, a lot of them they don't they haven't had enough sleep. So for them really going out in the morning and getting the morning light and you know, they're healthy, they can run, and they can do some activity. That's way much better. I'm talking about for the regular folks who are you know, a little bit of time that cannot go. Okay,

Claudia von Boeselager 1:37:38  
yeah, then.

Dr. Satchin Panda 1:37:40  
Yeah. Number six says your last meal should be at least three hours, ideally, four hours before going to bed. And in this last three hours before going to bed, you should also dim down your light. So not dim light and no food.

Claudia von Boeselager 1:38:00  
And ideally, meditators do something, read a book.

Yeah, come the nervous system.

Dr. Satchin Panda 1:38:07  
So these are the these are the six simple foundations for security and wisdom. And I guess almost everybody will benefit one way or the other.

Claudia von Boeselager 1:38:22  
Yeah, and for people listening, I'll put a summary together with this podcast episode of Dr. Patchin. Sanders, ultimate longevity, circadian rhythm optimization. And before we finish up, I'd like to ask a question, if you could live to 150 years old, with excellent health. How would you spend it?

Dr. Satchin Panda 1:38:42  
150 years? Yeah, so the idea is very simple. And every 10 years, you have to reinvent yourself do something new,

Claudia von Boeselager 1:38:50  
like Madonna?

Dr. Satchin Panda 1:38:53  
Yeah, I mean, actually, he says he's an amazing person. People love her or hate her. But that's for the sign of successful people. Yeah. Yeah, it's very far. No, that's true in everybody's life. Like, we have to reinvent ourselves; we have to do something new. And when I look at my own personal and professional career, the first 10 years were light. The second 10 years was timeless eating. And then now I'm really interested in this exercise and the balance between exercise and nutrition, how the optimum balance can drive a lot of performance, and then the sub-optimal balance can feel good now but can have adverse effects. So similarly, every 10 years come up with a new idea, and in the world is so big, there are so many interests that just leave for curious. Yeah, stay curious.

Claudia von Boeselager 1:39:53  
I love it. Where can people learn more about what you're up to? And what would you like to share with people any website, donations for your lab, social media etc.

Dr. Satchin Panda 1:40:07  
Yeah, so much of my research actually made headlines, for example, the discovery of blue light-sensing protein and then time retweeting. Many of these were not funded by federal grants that typically fund research. But those are mostly funded by philanthropy, foundations, etc. So that's why when individuals, whether it's small donations or big donors, it doesn't matter when they donate to my lab, they can donate by panda.sock.edu/giving, I guess, or donate, I guess you can put it on this or not, then that helps us to go try risky, high risk, high impact kind of experiments. And so that helps. Even small donations help in the sense we have a lot of young trainees who could have gotten a much better job, you know, selling products or writing codes for big tech companies, but they decided to do science. And these donations help them to go to conferences and meetings to present their work, and sometimes they have young children, they can find daycare for their children when they're going and going to conferences. I remember there was a nice call for funding by Jonas Salk because I and I work in the Salk Institute, Jonas Salk who made the folly of action. And Seattle because he said, Well, you're this was in 70s, right? So things are very cheap. He said You're $1 donation will buy a lab coat for the researcher. And your $1,000 donation will give the researcher all the reasons he needs for one week.

Claudia von Boeselager 1:42:05  
Prices have gone up a little bit since then, as well.

Dr. Satchin Panda 1:42:10  
So that's what I learned. Second i i tried to be active on Twitter. So my Twitter handle is satchinpanda. And then also, try to be active on Instagram as satchin.panda. So those are the two. And then we do have two different entities. One is mycircadianclock.org which is a research app, that people can download and sign up for and share their own habits with us. So that's completely research. So we don't sell information all the data is anonymized. And then I also have a commercial app called Get on Timeout. This is for people to pay a little subscription and then track how they are following their circadian rhythm. So those are some of the resources people can have access to. Perfect. And

Claudia von Boeselager 1:43:01  
we'll link everything in the show notes. Section. Do you have any final recommendations or any parting thoughts or messages for my audience today,

Dr. Satchin Panda 1:43:10  
I think we will always think of longevity, as, as you said, living off 250 years or something like that. But in my mind, longevity starts every single day, every single day. We should feel like we are at our big performance. We beat yesterday's performance, something like that, to be held in single every single day is what matters. And those of you who are not thinking that, why should you live up to 150 years 100 years or was wise to not enjoy your life now by engaging in unhealthy habit of being very expensive. It's not easy. You might think it's not God, but it's very expensive for you, as your medical bill is also socially and emotionally very expensive and taxing for all the loved ones around you. Because when we fall sick, we become a burden on our loved ones. The best thing we can give to our loved ones, whether it's our children or spouse, is to give them a worry-free day so that they are not worrying about their health, their disease, their doctor's appointments, etc. So that's the that's certainly the drive to leave live out east.

Claudia von Boeselager 1:44:33  
And arguably, if you're living healthy today, you have more energy, you feel more vibrant, and you're actually living better and having more fun, too. So on that note, thank you so much. I know we've gone on for quite a while I just saw the time. Thank you so much for your time today. It's been such a pleasure to have you on and sharing your wonderful work. Thank you so much.

Dr. Satchin Panda 1:44:53  
Thank you. I'm having corporate security.