 There's a lot of buzz on social media right now about determining your biological age versus the chronological age. For example, Brian Johnson, a 45-year-old tech entrepreneur, has been in the news and social media for dumping roughly $2 million annually into slowing his own aging down. Of course, I'm a big devotee of the pursuit of dying young at a ripe old age. In fact, I've written an entire book about it. And there's much more about how to de-age in my upcoming book. Got to check. Also, there's a slew of companies out there claiming that they can give you your biological age for a fee, of course. So what is biological age versus chronological age? Chronological age basically goes how many times you've been around the sun. In other words, your actual age in years. That's a chronological age. A biological age, on the other hand, claims to tell you how you might compare to other people of a chronological age of younger. And so, for instance, I just turned 73. That's my chronological age. But personally, I'd like to know if my biological age is a lot younger than my chronological age or, conversely, I might really want to know if my biological age is a lot worse than my chronological age. In other words, what if I'm 40 and my biological age is 73? I probably wouldn't want to have that, and I'd want to know steps that have made me, so quote, biologically old despite being young chronologically. And I've written about, I've done podcasts about, when I was 40, I was much older than I am now by many measurements. So how can we potentially measure biologic age? Well, there are ways of looking at this that are touted, and there's some interesting experimental evidence that gives us hope that some of these tests, or all of these tests, can give us an idea of what our biologic age is rather than our chronological age. For instance, one of the first attempts at looking at this was the length of telomeres. Now most people have heard of telomeres, but if you haven't, there are little end caps on the ends of your chromosomes. Chromosomes, of course, are where our DNA is kept. And these little caps, the ends of these chromosomes, there is some correlation between telomere length, or the thickness of those caps, and your biologic age. In other words, the longer or thicker these caps on your telomeres are, the younger you are. Now, unfortunately, the science is not perfect in this. In fact, there is some contradictory evidence that maybe in some cells, a shorter telomere might actually correlate with good things happening rather than bad things happening. And there's some evidence that a longer telomere is a good thing. My personal feeling is, although you can measure telomere length, I'm not ready for prime time on this one. There are compounds that have been associated with lengthening telomere. I talk about them in my other books, and I'm not going to bore you now. But there's some evidence that some of these compounds may increase telomere length, and are they worth your money? That's for me to decide and you to decide, but I got better things for you to worry about. Now one of the most recent exciting areas is in epigenetics, epigenetic markers. We've learned since the Human Genome Project that we thought we were in the most complex genome of any animal, only to find out that our genome isn't very interesting. In fact, there are animals like the sand flea that has far more genes than we do. And that makes us pretty poor. In fact, corn has more genes than you do. So if it wasn't for our complexity, we thought it was our genes, and in fact, it wasn't. But it's how genes are turned on or turned off that seems to be the magic of what makes us so distinctive. And so the epigenetic signal of how genes are turned on and turned off has become the darling of aging. Now, why is that? Well, one of the things that's been intriguing recently is the methylization of genes, of DNA. And methyl groups, you've heard me talk about before. I've written about them before. Methyl groups are a carbon atom and three hydrogen atoms, CH3. And methyl groups are one of the distinct ways we turn DNA on or turn DNA off. And most of the time, we want methyl groups to do the turning off and turning on. In fact, one of the interesting things about methyl groups is about 50% of us carry mutations of genes that are called the MTHFR genes that make enzymes that attach methyl groups to multiple B vitamins like B12 and folic acid. And about 50% of us lack one or more of these genes that do that. So 50% of us may lack the amount of methyl groups that we need to turn off DNA or turn on DNA. Now, why is that important? Well, the more we're looking at how DNA is activated or suppressed in terms of cancer, the more we think that this is a valuable way of just seeing what our status is. And there are researchers who have come up with indexes of methylation of DNA as a way of looking at biological age. And you'll see some of my compatriots talk about their chronological age and then tell you that their biological age based on DNA methylation is dramatically lower. And that is why they believe they're so much younger than they may actually look or certainly in terms of celebrating birthdays. Now, there's another area that's getting excitement and that is looking at protein unfolding and not to bore you to tears. But we used to think of proteins as these being long chemical structures because that's how we could draw them on a blackboard or in a book. But we now know that proteins actually are in a three dimensional shape. And it's how those proteins are folded or not folded that actually makes them active or not active. Why that's interesting is much of the research in, for instance, dementia or Alzheimer's shows that part of the whole problem is that these proteins are misfolded or not folded properly. And it's the kinks in the folding of the proteins, almost like origami that makes them work or not work. And so that's the next frontier of looking at aging is, well, how well do your proteins fold and unfold? And can we measure that at least in a clinical test? Now, quite frankly, I've never had any of these tests done on me and I have no interest in doing them. Why is that? Because with every passing year, since the human microbiome project got completed in 2017, the evidence is that it's actually the interaction between the species of microbes in our gut, in our mouth, on our skin that actually is the major impact of all of these other processes. And that's what's, to me, so exciting. And that, to me, confirms Hippocrates, dictum, 2500 years ago, that all disease, all disease begins in the gut. And I think I could safely say, based on his knowledge and the knowledge from the human microbiome project, that all aging begins in the gut. Now, why is that so important? Because if all aging begins in the gut, then that's where we should look to slow down aging or reverse aging. Now, there's a very famous model of aging that has stood the test of time. There's this cute little worm called C. elegans, and it's a little flatworm. And the interesting thing about this flatworm is that so far, all the anti-aging strategies that have ever been developed, including things like my friend David Sinclair's favorite compound, Resveratrol, in red wine, by the way. All these various compounds, polyphenols in anti-aging, have been tested in C. elegans first. And whatever has been tested in C. elegans has always stood the test of moving to a higher model. And what's fascinating about C. elegans is C. elegans actually eats bacteria. But C. elegans has its own microbiome. And C. elegans has its own digestive tract, a very rudimentary digestive tract. But just like our digestive tract, its cell, its wall, between what it swallows and the rest of it, is only one cell thick, just like ours. Now, ours is significantly longer. As you know, ours is the same surface area as a tennis court. But it's still only one cell thick. And what's been shown in C. elegans is that that animal only lives as long as that gut barrier is intact. And as that gut barrier breaks down as gaps develop in the wall of that little animal's gut, that's when it starts to age. And that's when it starts to die. And so the integrity of that gut wall determines how long that animal lives. Now, if that's the case, and it certainly does, then Hippocrates was right that all disease begins in the gut. And for that matter, aging begins in the gut. As our gut wall ages, as it begins to fall apart, so do we. Now, my last couple of books have been trying to educate myself and others about the process that causes that gut wall to break down. And the new book, Gut Check, goes into that even further. So what? Well, it turns out that we're now beginning to determine, by looking at people who are 105 years old, what sort of gut microbiome they have that makes them so unique at 105 years old? Why aren't they aging 105-year-olds? Why are they young? And it turns out that the composition of these gut biome is remarkably similar, no matter where these people live, whether they're in Japan, whether in the Mediterranean, whether up in North Dakota. And it's the composition of this gut microbiome and the postbiotic compounds that their microbiome make that actually determines why they happen to be 105, 110 years old and don't show the typical signs of aging. So for me, with every passing year, we get to experience what compounds are unique to these superagers. And we can begin to find out what the bacteria of these superagers like to eat that made these bacteria stick around in these superagers. And that's what's so exciting. For instance, two weeks ago, a fascinating paper was published that a product of bile acid metabolism and bile acid comes from bile made by your liver, squirted out by your gallbladder. It turns out that certain bacteria like certain compounds in bile, and if you have the right bacteria and the right bile acids, they make some really cool compounds that actually go to your brain and keep your brain really young. And when they look at super old people, they find that son of a gun, these super old people have bacteria that like to eat these bile acids and they produce compounds that keep these super old people brains healthy. So to me, it's which came first, the chicken or the egg. Believe me, which came first is your gut microbiome. You are a symbiotic organism. You are the home to 100 trillion different bacteria, fungi, viruses that have an interest in keeping their home alive, as long as you will give them what they need to eat. And that's the principle of my last three books. If you give your gut microbiome what they need, they will take care of you. And the exciting thing about the Human Microbiome Project is we're beginning now to understand which bacteria we need and what those bacteria want to eat so that they will produce compounds that keep that single cell layer of your gut wall intact. And that's the exciting thing that we don't need all of these other tests to do. We just need to go back to the basics that Apocrates figured out 2,500 years ago that all disease begins in the gut. You take care of your gut. You don't have to worry about your biological age because you will die young at a ripe old age. Remember, nobody's getting out alive. Sorry about that. But you want to have health span that is excessively long and still be biologically extremely young. So how do you tell how your gut's doing? Well, there's pretty easy ways to do it. One of the surprising things that so many of my patients come to me and say, you said that you'll know when your gut's in good shape that you don't need toilet paper anymore. And to bring home a valuable lesson, if you wipe and see something on your toilet paper, you probably don't have perfect gut health. And you wouldn't believe the number of my patients who walk in finally and say, oh my gosh, you were right. I had no idea that this was possible. And all you got to do is check out your dogs. They don't need toilet paper. Your cat doesn't need toilet paper. A bear going in the woods doesn't need toilet paper. There's a reason behind that because in general, they have a really good balance of microbiome. How else do you tell? Well, if you have an autoimmune disease, I can guarantee you that you have a dysfunctional, dysbiotic gut microbiome, number one. And number two, you have a leaky gut. You have a breakdown in your gut barrier. And just last week, I got a wonderful review of someone who's eczema for 20 years, miraculously went away when he went on the plant paradox program. And he was delighted, obviously, and shocked. But since 80% of my patients are now autoimmune patients who've kind of run out of options, that's important. Just last week, surprise, surprise, a paper was published that biologics used in the treatment of eczema, of psoriasis, actually made Crohn's rheumatoid arthritis and lupus markers worse. Can you imagine? You're taking a biologic to relieve one autoimmune disease and it's actually worsening other autoimmune diseases within you. And I see this all the time with my patients. So biologics are not the answer. The answer is getting good microbiome. So your biologic age may be 45, but what we wanna do is get you to a biologic feeling of like you were in 20. All right, are there other tests that you can use to really give you a quick and dirty way of how fast or how slow you're aging? Is there a crystal ball that's cheap and accessible? And yeah, I haven't think there is. First of all, get yourself a fasting insulin level. That's different than a hemoglobin A1C. You see hemoglobin A1C on TV every night. I got my A1C down. Good for you. That looks at how you're handling sugars and proteins for two months prior to the test. That doesn't tell you how you're going about handling those. And so many patients that I see with a normal or even low hemoglobin A1C have an elevated fasting insulin level. And a fasting insulin level is one of the best markers for aging. If you wanna step it up another level, get yourself a insulin-like growth factor one level. IGF-1. Now, if you're 40 or below, you actually are going to have a high insulin-like growth factor. But as you age, super-agers have a very low insulin-like growth factor. And you want to be able to follow this and read my books to find out how to control this. Now, one of the things that worry most people is we do know that muscle mass, as you age, correlates not only with longevity, but also in your ability to function as a moving animal. Now, does that mean you have to go to the gym to get muscle mass? Well, absolutely not. One of the things that's remarkable about super-old people is that they've never been to the gym in their lives. Just last week in one of the major magazines, there was a very large editorial by physical therapist and fitness trainer who gave it up, who realized that the fitness industry and machines was probably one of the worst things that ever happened to our health. Because we no longer, based on machines and gyms, move our body through ways that our body was designed to move. And he proposes that if you actually wanted to have good fitness, that you should do what super-agers do, which I've been saying all along. First of all, you need to get out and walk. Secondly, if at all possible, work against gravity. Now, it doesn't matter that you go up a hill, you can go down a hill. And there have been some very interesting papers that I've talked about from Austria, having people either ride a tram up a mountain and then walk down or to hike up the mountain and ride the tram down. Now, needless to say, most people would volunteer for the ride up and the walk down, but they divided people into group and they wanted to look at their muscle mass. And the thought was the people going up they were gonna have a lot better muscle mass than the people going downhill. Well, they found the exact opposite was true that both of them actually had significant changes in their muscle mass. And the surprising thing was that the people going downhill actually had slightly better muscle mass and that's because they were working against gravity and exercise that shortens muscles actually is more efficient than exercise that lengthens muscles. So, in the end, long story short, get out there and move, buy a dog, get a dog from a rescue shelter. It's one of the best investments in your long-term health that you can get. There are plenty of easy to read books about how your body is your own gym and you can get a complete workout without ever going to a gym in the privacy of your own home. If you're worried about body shaming, get a book. Your body is your own gym is a great place to start. Finally, there are a lot of influencers that are convinced that certain prescription drugs like metformin, like rapamycin, may be the key to longevity. And there are some of my colleagues who dabble in these prescriptions. Now, I have no problem using metformin as a prescription to treat somebody who's a diabetic who I first see. I personally don't have a problem in someone who just had a stent or a coronary bypass in using a statin drug as an anti-inflammatory until I can get the process that caused the problem under control and corrected. Just like I would have no problem on putting a cast on someone's leg if they have a broken bone, but you're not gonna wear a cast the rest of your life. You're gonna wait for the bone to heal and then you don't need the cast. Similarly, we don't need drugs to accomplish what anti-aging can be done by having a properly constructed microbiome and giving the microbiome what they need. And then the drugs aren't needed. Interestingly enough, metformin, this amazing anti-aging drug, actually works by changing the microbiome to a more friendly microbiome, son of a gun who knew. So that's my practice in my office. I'm not afraid to use a drug when we need it temporarily but then to get a person on the road to getting their microbiome and their gut well stabilized and you'll know in an instant how that's going along with the toilet paper test. Finally, skin is merely a reflection of what's going on in the gut. People are shocked with the changes they see and what they assume was old age on their hand, on their skin, in their wrinkles once they see what's going on with their gut. And not a day goes by that somebody wants to look at my hands when I'm across them and going, let me see your hands. What the heck is that all about? Yeah, my wife's a perfect example. She was a marathon runner. She was thin. She was eating quote healthy foods that were lectin rich. And once we took those lectin rich foods away from her, her skin changed dramatically. And what she thought was a normal process of aging and potentially sun damage wasn't that at all. It was actually a reflection of the damage that had been being done to her gut by these lectin rich foods. And once we removed them, changes on her skin were obvious. And she was pretty happy about that. So all skin is merely a reflection of what's going on in the wall of your gut. Lots of easy ways that don't cost really any money or very little money to reverse your biological age. Don't worry about your chronological age. Let things take care of themselves. After all, we wanna be superagers and we know now the tricks of super aging relate to what's going on with your microbiome. And that's an easy fix. And my books are a great guidebook to how you get there. More amazing episodes just like this one. Watch now. Fish oil actually sends signals to your brain that actually modulate your food intake. In other words, makes you eat less and you're less hungry.