Do you want to die? How Bryan Johnson plans to cheat death

What if optimizing your sleep could significantly extend your lifespan?

In this episode, we dive deep into the science of longevity with Bryan Johnson, the entrepreneur spending millions to reverse aging, and Prof. Tim Spector, one of the world’s top 100 most-cited scientists and an expert in nutrition and the microbiome.

Bryan has dedicated his life and his body to testing cutting-edge health interventions to slow down aging. His meticulous approach to sleep, diet, and exercise has sparked global debate. But how much of it is backed by science?

Tim Spector joins the conversation to separate fact from fiction, revealing what actually works when it comes to sleep, longevity, and optimizing health.

Could better sleep really help you live longer? Tune in to find out.

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Transcript

Jonathan Wolf:  Bryan, thank you for joining me today. 

Bryan Johnson: Glad to be here. 

Jonathan Wolf: It's a pleasure. And Tim, thanks for being here as well. 

Tim Spector: That's going to be great. 

Jonathan Wolf: So  Bryan, we have a tradition here at ZOE where we always start with a quick-fire round of questions from our listeners, with very strict rules. You can say yes or no, or if you have to, a one-sentence answer.

Are you willing to give it a go? 

Bryan Johnson: Yes. Let's do it.

Jonathan Wolf: All right. Did you spend $2 million a year to slow your speed of aging? 

Bryan Johnson: Yes. 

Jonathan Wolf: Do you think you can halt aging?

Bryan Johnson: Yes. 

Jonathan Wolf: Do you hope to prevent your own death? 

Bryan Johnson: Yes.

Jonathan Wolf: Have you discovered steps to slow aging that anyone can adopt? 

Bryan Johnson: Yes. 

Jonathan Wolf: Tim, I'm 49 years old, if I have the right lifestyle could my body's biological age be a lot younger than that?

Tim Spector: Definitely. 

Jonathan Wolf: Can the right diet slow down aging? 

Tim Spector: Absolutely. 

Jonathan Wolf: And  Bryan, you can have a whole sentence for this. What's the most common misconception about aging? 

Bryan Johnson: That you can do something about it. Life choices can make a meaningful difference in the way and the speed at which someone ages. 

Jonathan Wolf: Hey, that's amazing. And I think those answers are really striking. And so I'm very excited to sort of go through this, through, the podcast. 

I'd also say that this is the first episode we've ever recorded in a guest's house, and it feels very appropriate given today's focus. 

Because instead of diving into a specific nutrition or science topic, we're basically talking about the science of you, Brad, today. Your lifestyle, your routines, the choices you make right here under this roof and especially in this kitchen. 

Because you're conducting a scientific experiment on yourself, aren't you? 

Bryan Johnson: I am. 

Jonathan Wolf: And then you're sharing it with the world. You basically say that the choices you've been following put you in the top 1% for a whole variety of health markers from muscle mass to inflammation.

And you've now slowed your rate of aging to be, I think, better than 99% of 20-year-olds. 

Bryan Johnson: That's right. 

Jonathan Wolf: So I'd like to start by talking about how you got here. So can I start with what is project blueprint and why did you start it? 

Bryan Johnson: You know, every generation going back hundreds and thousands of years, they pose questions about what is possible.

In the 1960s, it was Can we go to the moon, or in the early 2000s, late 1990s, early 2000s, it was Can we sequence the human genome? 

So humans pose these big questions, can we do a given thing? And I wondered if the relevant question for our time and place was, will we be the first generation to not die?

Jonathan Wolf: I love the question. How does Project Blueprint fit into that? 

Bryan Johnson: We wanted to approach this question scientifically. So I hired 30 medical professionals and we went through this process where we evaluated all the scientific literature on health span and lifespan. 

We tried to grade the evidence that we could identify. Do we think, for example, a given therapy, let's say it slows down the speed of aging or reverses aging damage to a certain degree? Do we believe the evidence? 

And then we stacked ranked all the evidence and said, okay, we have our list and let's just start with number one, and let's do that therapy or that measurement. 

And so we had a firm principle that we would do everything based upon measurement and scientific evidence. And so I became the most measured person in human history. There's more data on my body than anyone before me. 

We've just gone through this process of measurement and application of the science again and again. And I think it's possible that I have the best comprehensive health markers of anybody in the world. 

I take 50 different markers from my sleep quality to my inflammation levels, to uric acid, to muscle, to fat, to take any marker.

We're going to share this actually in the next coming days, but it's really a contemplation of what does health look like and comprehensively from how you sleep to what your microbiome looks like, to your biological age, your methylation patterns. 

So we've really tried to just do this by the data and numbers and with as little storytelling as possible.

Jonathan Wolf: And  Bryan, when you say the best possible markers, do you mean the best possible markers for someone of your age, or are you saying that they're better than my 16-year-old son? 

Bryan Johnson: And so in every biological age marker, there's typically an ideal age. 

So for example, in grip strength, as you grow older you increase in grip strength, a capacity that you hit a certain age and you decline in grip age to capacity. That is true for a lot of things. That's your cardiovascular fitness, it peaks at age 18 and then declines from there. 

So we've tried to identify the peak health level of every category of every marker and we try to peg that. So we say what is peak cardiovascular fitness for an 18 year old and then how do I achieve that?

For example, my cardiovascular fitness is equal to the top 1.5% of 18-year-olds as measured by VO2 max. 

We completed a test today looking at the oxygenation of muscles. And so that's also a marker of age. So the oxygenation of my muscle is in the top 5% of18-year-oldss, elite swimmers.

So we try to find peak levels and then peg my markers to that as best we can. 

Jonathan Wolf: If I understand right, you are saying that yes, you are better than my 16-year-old son, basically on all of these markers. 

Bryan Johnson: Yes. I mean, conventional wisdom would say a 47-year-old could never be as healthy as a 16-year-old. 

Now, in certain regards, that's probably true, right? They have the anatomy of a 16-year-old, I have the anatomy of a 47-year-old, and there are just some things our technologies can't do today. 

However, if you compare the 16-year-old and me on these markers, inflammation, sleep quality, cardiovascular ability, and bone marrow density down the line, it's possible my health markers are in fact better than the 16-year-olds.

Jonathan Wolf: That's amazing. Now you mentioned already something about the pace of aging. It came up a little bit at the beginning, these questions about, can you halt aging? And you said, yes, you hope to be able to halt aging and prevent your own death. 

How do you measure aging? And so what does it mean when you say you want to halt it?

Bryan Johnson: Yeah, we are measuring the biological age of my organs through a few different modalities. Actually, a ton of modalities. 

But you can take the heart for example. You can measure the biological age of the heart anatomically to say what kind of cells are in there. You can also measure from a functional perspective. What is your resting heart rate? What is your max heart rate? 

And so we try to look at every single organ according to the anatomy and every organ according to the function, and then also the biological processes. 

And this speed of aging you're talking about is DNA methylation. So our body expresses certain patterns in terms of the way it expresses these methylation patterns and they're called epigenetic clocks.

And so the science became emergent a few years ago. We thought it was very promising. And so we started measuring my epigenetic age every week for the past few years. So I'm the most methylated-measured person in the world. 

And, we've tried to titrate what things increase the speed of aging and which things slow the speed of aging.

I think it was actually interesting. There was a paper published last week with Yale with 16 epigenetic clocks, trying to find macro patterns of what increased the speed of aging of what things decreased the speed of aging. 

And so, in doing this, I started with my speed of aging just over one, which is faster than normal. And now my speed of aging is 0.64. 

To make this fun, I created an Olympic sport. I created the rejuvenation olympics.com. And I said, all right, everybody in the world, we're going to play a fun game. Test your speed of aging using these DNA methylation clocks and see who gets the lowest score.

And so it's been a really fun thing because, in health and wellness, people like to flex their health. They like to stick to signals others like my testosterone level is this, or I do a cold plunge this, or I do sauna. People like to really share what they're doing and oftentimes it's storytelling more than data.

I wanted to say, can we find one marker that's just fun to compete on that everybody can do easily. And it's a nice comparison point. So that's been a lot of fun to get people excited that you can actually quantifiably measure the body. 

Jonathan Wolf: I think that's quite funny. I agree that I quite like to talk about the really healthy food I have, but I don't like to talk about the entire bar of chocolate that I eat on the couch at 10.30 PM. So here you're saying there's one number that you can't escape from.  

Has anyone beaten your number? 

Bryan Johnson: Yes, I'm currently number, I think, five or six in the world. And so what's been fun about this is, when I started this, I said my goal is not to be number one. I mean, I'd love to be number one, but my goal is to help others beat me.

So I'm going to share everything I do. And then if you can take what I do and improve upon it, that's better than to just share with everyone else. 

I met some person the other day that's I think, number two or number three. He's a biochemist. And I said, what are you doing? He said nothing. I do absolutely nothing for my health. And I said, amazing. And he said, I think I have a hypothesis on what genetic profile I have, which leads me to basically have this as a genetic disposition. 

So that's what I think the positive benefit here is that when this data is shared and the community is involved, the people can then start saying, here's me, here's what I do and then everyone learns much faster. 

So that was a cool thing, you've got me doing a whole bunch of stuff, to him who does nothing, but yet he's still beating me just by a point. 

Tim Spector: I used to have the same thing with my gut health when we started in the company, I was sort of number one, and then we started making it public and I kept dropping down the ranks as other people said, Hey, I'm above you, Tim.

But it is great to get people involved in these things. And you realize as you expand it, you can't be number one for very long. 

Jonathan Wolf: I actually had dinner with one of my friends a little while ago who had just completed the ZOE test kit and he measured his microbiome as part of this and he showed me his results and I felt it was so unfair. 

He had 48 of the 50 good bugs, he just started, and he hadn't done anything to change his diet. I've been struggling for years, slowly picking this up. 

So there can be something quite frustrating, I think, about, I can imagine the person beating you who's done nothing. You're like, but I'm working so hard. But I love the idea of the shared information.

So I want to come back to another one of those first questions because you were saying that you thought you could halt aging completely, which I guess means you go from 0.64 to a rate of aging of zero. Is that really possible? 

Bryan Johnson: Yeah. So I think the most sober answer to this question is that we do not know right now how to achieve that. I don't think it's possible with current technology and current science to actually arrest aging. 

So what I really am excited about is I think that if you evaluate the speed at which artificial intelligence is advancing, it's possible that we will achieve decades, if not a century worth of progress in the coming years when we have more intelligence to help us do the research and the discovery that we will experience a renaissance.

And so what I'm really trying to do is, I'm trying to say, from the broadest perspective, if you imagine being present in the 25th century, so a few hundred years into the future, and they're looking back at us right now, just like we look back at the 15th century and we say, of course, that thing happened and then it flourished and that dimension was made and it was so obvious it could have been done.

I think the 25th century would say about this moment, they would say, Oh, of course, that's when humans figured out that they were transitioning from death being inevitable to extending their lifespans to some unknown horizon. 

Not that we had solved immortality, but that we had acquired the basic technological medical ability to say there are legitimate reasons to have hope that we may be in a new era of being human 

Jonathan Wolf: And that doesn't just mean that you're going to make it to be a hundred and be healthy, you imagine you could be two hundred or three hundred or a thousand or something like that.

Bryan Johnson: Exactly. Two things. 

One is I don't think anyone can say anything intelligent about the human race even one year from now. I think that's how fast things are changing. I think our ability to guess is increasingly having a lower probability. 

The number two is there's never been a reason to have more excitement that we really are becoming a new thing. And so yet this is not about me thinking that can be 80, 120, 140. I think we would artificially limit our imagination. 

I think it's proper to say we don't know how long and how well we can live with no constraints. 

Jonathan Wolf:  Bryan just listen to all of this,  do you see yourself as a role model or a test subject? I'm sort of thinking you were describing going to the moon before and I'm thinking about all of those crazy test pilots are doing really dangerous things to go to the moon and in the end we just get on planes a lot. We never had to take that same risk. 

So should we end up all living like you or are you sort of showing us the future but hopefully there'll be an easier way for the rest of us? 

 Bryan Johnson: Yeah, I think about it from a historical perspective where if you look back through history we exist in a few large ideological systems.

So I'd say if you go back to Confucius, where he said the societal structures have built this familial relationship where it's very common in the Eastern world. 

Then Buddha said, Hey, there's the ego death and the fourfold path and reincarnation, he introduced this philosophy. Then Mohammed said, submit to God. Jesus said I am the son of God. Adam Smith said there's this invisible hand and markets and capitalism. America said, we, the people. Karl Marx said it's class warfare. 

So over time, these ideologies have emerged to address new technological and social abilities. And I think right now is the first time in about 2000 years where a new ideology could emerge as a species.

And so I don't view this as something just trying to be fit. I don't see this as something trying to live forever. 

I think we are in a moment where there's this opening to re-imagine existence wholesale. From the perspective of when death is inevitable, we do things a certain way when we extend our lifespans, it's very, very different.

And that's where I do this don't-die framework. Where don't die, I'm proposing is the new ideology for us, the species politically, economically, morally, socially, ethically, spiritually, and religiously. That just democracy changed the way we run government, don't die is the new operating system of humanity across everything we do.

Jonathan Wolf: That is definitely a bigger conversation than we've ever had on the ZOE podcast before. So I'm a bit blown away by that. I'm gonna have to think about it.

On this pathway, when you're figuring this out, how did you decide which scientific studies will be implemented into the blueprint? 

Bryan Johnson: I'd say it's both a science and an art, Tim, as you probably would say that it's… 

Tim Spector: A bit of guesswork.

Bryan Johnson: Yeah. I'm not sure. I think if you maybe asked five scientists for approaches to how to choose the best evidence, you probably will find some commonalities. 

But I would also guess you'd probably find a lot of disagreement in terms of how to decide. I'd say probably much more art than there's a science, but we did our best.

We'll try to use gold standard studies for best as possible and things like that. We prefer human models over animal models, et cetera. But when you, when you get to lower gradients, it's just harder, more discernment is required. 

Jonathan Wolf: Actually, we'd love to bring Tim in here because I mean, a lot of listeners to the show,  Bryan, are ZOE members, which means they've done this at-home test and they've got this app which has given them all this advice to understand what's best for them.

And Tim, you and the other scientists at ZOE constantly spend a lot of time trying to understand based upon our own research, but a lot of external studies, what is the best science to use? 

How do you think about, because people often use this word, I looked at the scientific literature and it tells me what to do. How did you do that? 

Tim Spector: Yeah, well, the bar is slightly different to  Bryan, because  Bryan is trying to say everything that might possibly work, let's give it a go. 

In a way, what we're trying to do for our ZOE members is to distill the science and give some practical tips to people that we are pretty sure are going to work rather than, Hey, it's got a one in a hundred chance.

So definitely, we take the gold standard, which is the randomized controlled trial, whatever it is. Whether it's a lifestyle intervention versus something else, or it's a vitamin or a pill or against a dummy. And that's generally what we've done. 

That's what we believe in at ZOE and even our own products, we use in that way.

Jonathan Wolf: And Tim, a mouse study, why doesn't that tell you what we should do? 

Tim Spector: Because for a number of reasons. Mice and humans are quite different. They have very short lifespans, two to three years compared to us, and the way the studies are done, they're often flawed. They're often highly inbred genetic mice that aren't resembling normal people out in the wild population, so it may not be generalizable.

Often, a lot of the research, you can do ten experiments and only report on the one that works. So there's often an inherent bias in a lot of these studies. 

A lot of people are very skeptical, they're quite useful to give you a new idea and then go and test it in humans. But on their own, a bit like test tube studies, you can get cells of the body and you add chemicals to it and you can see, oh, this has a big effect or it doesn't.

It's not real life. Because that test tube isn't in the complexity of the human body and understanding it all. So that's why there's a whole gradient of evidence between all these that makes it really hard. 

And that's why, in a way,  Bryan had such a hard time with these 30 experts, trying to say, how do we rank these things in order?

Particularly in this whole area of aging and longevity. There's a lack of really good randomized studies. 

Jonathan Wolf: So I think I've got a picture now, both of what you're trying to do,  Bryan, which is pretty amazing. The fact there are quite a lot of limitations, it sounds like, on the science that can just tell you what you should do. And there's these different areas, and it looks like you're nodding away and saying that.

So I understand a big part of your approach is basically to be your own test subject and to track and measure your own health over time because at the end of the day, you care about your own outcome and you can start to push forward the science by doing these studies on yourself. 

Bryan Johnson: Yes.

Jonathan Wolf: So I'd love maybe just to understand a bit more about that and maybe starting with, I know you mentioned before, 50 measurements and everything. 

I don't know whether it's possible to collapse that down to what are the most important measurements for you as you think about your overall health and that you track?

Bryan Johnson: Yeah, if you start with the things that most people agree upon, I think you could start and say, okay, being obese is not a good idea. Generally speaking, it's not recommended that it doesn't lead to good health outcomes. 

You could also say, having a poor cardiovascular ability is also not a good idea. It doesn't lead to good outcomes. 

So we've taken what would be some of the most sturdy measurements in health and wellness and we've said, okay, these health markers indicate optimal health. And we see that across the body. 

So we've taken those as the sturdy markers, and then we've taken the evidence and said, okay, now we can play with the scientific evidence.

But really what we care about are the markers. We care about what my cardiovascular ability is. We care what my speed of aging is. We care about, using MRI, what it says for my brain age, for the size of my hippocampus, you know, my gray matter, my white matter.

And so we've tried to say, what does an 18-year-old body look like and how does it function? And can my body look like and function like an 18-year-old in all these different aspects? 

Tim Spector: Do you check your immune system, inflammation levels, and things like that? Because I think that's quite an important one in aging, isn't it?

Bryan Johnson: We do. So we track high-sensitivity CRP, for example. We look at, ILS. So we look at a bunch of factors. Yes. 

Jonathan Wolf: You got all of these markers and it sounds like they're not the same ones as when I just go and see my physician but I didn't recognize a lot of the things you're talking about.

So they're pretty different from when I just go and see my doctor and he [says] your LDL is high.

Bryan Johnson: That's right. And so typically doctors have the most common access they have as a blood draw. So they're looking at, it's the typical panel of cholesterol markers, triglycerides, red blood cell count by blood cell count, et cetera.

And things are not looking at, for example, your sleep data. And so we know there are sleep patterns, for example, where as you age, it gets increasingly hard to get restful sleep and manifest, for example, where it takes a longer time to fall asleep. You're up more times the night than you would before you get less deep sleep, less REM sleep overall, less restorative sleep, and that has negative effects on the body.

So you actually age profile and say what is an optimal sleep pattern for a late teen, or early twenties person? And that's one of the metrics we use for that. 

So yes, the doctor looks at basic things, but nowhere even approaching the comprehensive set of markers across lifestyle and other things like that.

Jonathan Wolf: And so if you think about the bloods and sleep, is there any other big area that I think probably our listeners wouldn't even think about that you're measuring, 

Bryan Johnson: Let me give you maybe an unexpected one. Night time tumescence, night time erections. 

Jonathan Wolf: I was not expecting you to say that. It’s a first on this show, let's follow it in.

Bryan Johnson: So this was an accidental marker where we were doing a therapy, electromagnetic stimulation to rebuild... I was getting up to go to the bathroom one time per night in my sleep. And getting up to go to the bathroom is disruptive for you. You're waking up and you have to go back to sleep. It's just better to sleep the entire night. 

So we were trying to get me to zero wake events. And so to do that, I was trying to build bladder strength. The hypothesis was if I had stronger bladder control, then I would be able to not get up and go to the bathroom. I was reducing the amount of fluids I was drinking after four. 

So we're trying this two-prong approach. And in doing this, I sat on this… I have this device in the clinic upstairs and it was stimulating my muscles for my bladder. And it had this weird side effect where every time I woke up, I was experiencing a nighttime erection. And so I asked my team, why is this happening?

We started then looking at the research literature and we discovered that nighttime tumescence is a significant marker of health. An average 18-year-old has on average, just over two and a half hours of nighttime erections. It's a significant marker of cardiovascular physiological and sexual health, and as you age, it goes down.

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So an average 70-year-old would be down to less than 50 minutes per night. And if you're getting four to six hours of sleep a night, they go away entirely. And people who are not having nighttime erections are 70% more likely to die of prematurity. 

It's a topic that is comical when you hear the word. It's funny because it's kind of sexual and kind of weird, but also it's a pattern that repeats in males and females, so both genders, and it happens primarily in your REM sleep with the majority of it does.

So in that marker, my nighttime erections are three hours and eight minutes. So the length of the Titanic, which is better than an average 18 year old significantly. 

So in that marker, my body, so this is not something where I'm running on a race, I'm just going to sleep and my body is having these natural physiological cycles that are better than the average 18-year-old.

And so things like that, of course, you wouldn't even know this marker exists. There's no way a doctor would measure it.

Jonathan Wolf: I was actually going to ask, because you talked about measurement and that everything is measured. So have you got some sort of… are you wearing special equipment now when you go to bed in order to measure this?

Bryan Johnson: Yeah, you can use a little cube. It's about a centimeter cubed. It has a little strap. You just put it on the base of the penis and you think it would be uncomfortable, it's actually just fine. You put it on, you forget about it and then you go to sleep and it measures the engorgement penis. So it measures the engorgement size and order also the duration.

So a typical night, the average male will have between three and five erection episodes with different strengths and different durations. And so there's parameters on what is an ideal strength and duration. 

Tim Spector: And do you have patches on all of your bits of your body? Then when you go to sleep, is it quite complicated to get in your pajamas?

Bryan Johnson: No. So I have a bed that measures my sleep patterns and then I have a wearable on my wrist and then occasionally I don't do the erections every night. I just do it once a month or so. Yeah. So. Pretty minimal. 

Jonathan Wolf: I was starting to get this vision of you wired up in a hundred ways every time you go to sleep, but that's not right. 

Bryan Johnson: But I have the best recorded sleep score in history, so I have eight months of perfect sleep using a wearable.

Something that many people who've had wearables for years, they haven't done in one night. So I wanted to show that you can achieve high-quality sleep if you actually put your mind to it and create systems. But yeah, I don’t think anyone's even gotten close to being that.

Jonathan Wolf: I'd love to come, I guess, to what is having the most significant impact on those markers. 

So you're talking about all these different ways in which you're measuring your health, and then I think you're into, okay, so what can I change in order to improve? And that's my takeaway. 

What are the most significant things that you can do to really make a difference to aging? 

Bryan Johnson: Okay. Yes. I would say four things. And these are all things that everybody can do with a really minimal budget.

So one is sleep, two is exercise, three is a good diet, and then four is to try to drop the bad habits. Those are really the power laws. 

Jonathan Wolf: So sleep, exercise, nutrition, and dropping the bad habits. That's it. And bad habits, I'm guessing there's smoking and drinking too much and things like that that you know are bad habits. 

Bryan Johnson: Exactly. We all kind of know.

Jonathan Wolf: Before we start to move into all of this, Tim, you're one of the world's top 100 scientists, very, very credible in the traditional science way.

And you talked about in traditional science, you do these big randomized control trials with hundreds of people under very strong conditions. 

You're sitting there, listening to  Bryan with almost exact opposite, right? He's conducting his experiments on himself. Have you ever done this?

Tim Spector: I confess I have actually, so although I've been studying my twins for 30 years, 15,000 of them who are probably the best-studied research subjects in the world. 

There are some things you can't do with those twins and a lot of them are things like diet. There's no way ethically to do some of these experiments.

So when I had my mini-stroke back in 2011, I wanted to test myself in various ways. Change my diet and I've been doing a lot of experiments. So going vegan for six weeks was one of them. Measuring my blood pressure when I tried to restrict salt, finding no difference interestingly as many people also have done.

Then I went on the French cheese diet to see if really a high fat with virtually zero carbs for three days how I would feel. I wanted to do multiple experiments rather than… I couldn't imagine myself only eating cheese for the rest of my life. It turned out that my microbes didn't change in that time in the way I'd hoped them to. 

So then I got more into feeding the gut microbiome and fermentation. And, actually, I was going to do another experiment about McDonald's. And was going to eat 10 days only at McDonald's and see what the effect on my gut microbes. 

Luckily another volunteer, who liked McDonald's, was hard up for cash, and also happened to be my son, stepped forward, did the experiment for me, and ended up losing about 25% of his his gut microbes in that 10 days.

Jonathan Wolf: Can I just say, I think that's a brilliant thing that I wanted to ask about because, I think one question I think a lot of listeners will have listened to this is, is it safe to experiment on my health? 

You just gave an example where it sounds like the outcome wasn't good. So how should people, if you were going to advise anyone listening to this thinking about experimenting with their health, but wanting to do it safely, what would you be saying, Tim? 

Tim Spector: I think it's reasonable to explore particularly with say sleep exercise and food. If you do it for short periods of time and you're not going to overdo it, it's probably reasonably safe if you don't have any other medical conditions and you're fairly young and healthy.

For example, the McDonald's diet, 10 days was too long. We didn't know at the time that actually you could really sort of harm your gut microbes in a way that you hadn't thought about it. Whereas just doing it for 48 hours would probably be fine, you'd probably recover. 

I think everything I believe in now is about self-experimentation because everyone is different, and learning what sleep is good for you, how much exercise is good for you, what are the right diets, what are personalized to you, should you be on a high fat or a high carb diet.

These all require some self-experimentation. If you don't have access to things like the ZOE program, but I think I would do it for short periods of time.

The danger is if you overdo it and, in areas we don't fully understand. And I think the gut microbiome was one, certainly, when did this 10 years ago, we didn't understand quite how harmful some of these practices could be.

But I think we should really, everyone should be encouraged to some extent to do self-experimentation. Do you agree with that?

Bryan Johnson: Yeah. I mean, life is an experiment. So whether someone is actively opting into experiment, they are experimenting every second of every day.

 So when you decide to go to bed, you're doing an experiment. When you choose something from the menu, you're experimenting. Every decision you make is an experiment.

So the question is whether you have data just to inform you of the results of your experiment. 

Tim Spector: But what I think is really cool is that we've learned that, just with food, if you just record how you feel a few hours after eating it, in a notebook or something, you can get a pretty good idea of whether that food does agree with you or not.

And these are things we never thought of before, because we always assumed we were all the same. We all respond to exercise, food, and sleep the same way. 

But there are some experiments  Bryan's doing very methodical, and very technical, but I think everyone can just make a mental note to think about how does it make them feel. And I think if more people did that we'd be headed in a much better direction. 

Jonathan Wolf: I'm just thinking about the way that you've said that in a way, everybody's life is an experiment. You clearly have a lot of support infrastructure here. Right? So you're not randomly guessing at what you want to do.

How might someone who's thinking about what you're doing, apply it to themselves without the financial resources and everything you're able to bring to bear and want to make sure that they're not going to hurt themselves? They're more likely to benefit than not. 

Bryan Johnson: Yeah, there's a bunch of really easy starting points. 

So, for example, you know, in our evaluation of scientific literature, we couldn't find any evidence to suggest that McDonald's should be part of one's daily diet. 

 Jonathan Wolf: I think that it seems pretty safe to say. 

Bryan Johnson: We didn't find any evidence that a bedtime that varies by four or five hours a night is a good idea. We didn't find any evidence to suggest that no exercise is a good idea. 

So when you start from the negative perspective of what can we discern from that perspective, you can narrow down a lot of the option space. And then on the other side, most people spend the majority of their time in these highly technical conversations of like, is fresh salmon better than farm salmon and these comparative things find that you can have that conversation. 

But on the other side, there are a bunch of easy decisions you can make that have very powerful effects on your life. And that's where I would start for most people it's the big life habits, which are the most powerful things.

They're the hardest, but they also deliver the best results. 

Jonathan Wolf: So I'm going to want to turn to that in a minute, but there is one question that I have to ask. We had a lot of listeners ask us about it because some of your experiments have gained a lot of notoriety. 

I've been told that in one of those, you try to slow your aging by transfusing the blood of your, I think, 17-year-old son into your own body.

Are you still doing this? 

Bryan Johnson: Yeah. So the way that happened is, my father is 71 years old. He called me one day in a panic and he said, I just had this traumatic event where I was writing a thing for work, and I stepped away from my desk. I returned and I saw that what I had written was a jumbled mess. That I was experiencing cognitive decline in real-time, and I couldn't see it.

He said that surprised me because I thought that if I was experiencing cognitive decline, I would be aware of it. Oh, I'm now more forgetful or I can't remember someone's name, but this was happening outside of his awareness. And he said I'm panicking if I lose my mind. I lose my existence. And so he said, what can I do?

And that day, my team and I had had a call on plasma exchange. And we had seen that the evidence that things people were using it for, were for cognitive decline. There were several studies going on for Alzheimer's and Parkinson's, and we were saying, okay, that's interesting. Do we think we can bridge this therapy to anti-aging? Will this slow down my speed of aging? 

We were saying, we don't really know. Right. The evidence is not clear. There's no direct path, but we're open. And so I said, Dad, we were just talking about this therapy that people were using for cognitive decline, if you're interested, I'd be happy to give you a liter of my plasma.

And my son overheard this conversation. He said, I'm in. And I said, okay, guys,   we will do a family plasma exchange activity. So, Talmage, you give me your liter of plasma, Dad, I'll give you a liter of plasma. We'll do it.

So it [was] kind of this, you know, smile on our face, what the hell, we might as well because there's millions of transfusions that happen daily. It's very safe. It's been happening for decades. It's not a very risky therapy. So, fortunately, we are all blood types the same. So that happened, and we did the therapy. 

Interestingly, from my son to me, I experienced no change in my biomarkers. It's not to say something positive didn't happen. We just couldn't detect it through any of our measurements.

And then number two is my father, his speed of aging, according to methylation patterns, lowered by 25 years equivalent. And it stayed that way for six months and he had a remarkable comeback in his cognitive abilities over that duration of time.

His coworkers were saying, what is going on? So it was interesting, no effects for me, but for my father, it was pretty meaningful. And so it was actually pretty similar to what the animal models showed in terms of the old and the young rat doing exchange. 

Tim Spector: And you didn't drive fecal transplants because there've been animal studies showing that, from young to old they can reverse the aging there. Is that the next for the family? Will you mention that to your son?

Bryan Johnson: We have been trying to do that. And so in fact, there's a U.K. company we've been talking to. We've been trying to take my microbiome and make it into a supplement. So kind of a joke, but also kind of serious.

But yeah, in the U.S. it’s… 

Tim Spector: The mouse data is quite similar to the plasma one, you know.

Bryan Johnson: Agreed. So it's definitely been on our list. 

In the U.S. it's a regulated one. So we couldn't do a supplement. It'd have to be Rx [prescriptio] and doing Rx it's a drug. We have to leave the country and exactly. But yeah, we think it's interesting and I definitely would be down to try it. 

Jonathan Wolf: I can see that family dinner at the Johnson family table, it's quite different from mine, but maybe not as different from Tim's as you might imagine, where he's like, son, I've got this experiment for you.

Tim Spector: It's a common topic in our house as well, yes. 

Jonathan Wolf: I'd love to move us on to actionable advice and this is ZOE Science and Nutrition, I'd love to really focus on nutrition. Could you talk us through your daily food routine? And I guess also why. 

Bryan Johnson: So I eat 2,250 calories a day. I'm vegan, although I chose to be vegan for ethical reasons. I think we want to be what we want AI to become, and I think we want AI to treat us like we treat other forms of intelligence. So I'm vegan, and my diet consists of the following foods. 

So in the morning, I'll have what I call super veggie, which is broccoli, cauliflower, black lentils, hemp seed, garlic, and ginger. And then I'll put some extra virgin olive oil on it, a 15ml.

Then I'll have the next dish, which is nutty pudding, which is macadamia nuts, walnuts, flaxseed, pomegranate juice, and berries; black, blue, and raspberry, strawberries. 

And then I'll have a final bill of the day, which varies every day, according to vegetables, legumes, berries, nuts, and seeds. I'll have three tablespoons or 45ml a day of extra virgin olive oil.

That's my primary intake of those general categories of foods. I also do pea and hemp protein, so I do 110 grams a day of protein, 

Jonathan Wolf: 110 grams. You're adding a lot of protein as a supplement then to that food? 

Bryan Johnson: Yeah, so I do collagen, so collagen peptides are the only thing I do that is non-vegan.

So I do  20 grams a day of collagen protein,40 grams a day of pea and hemp, and then the remainder is formed of legumes and other sources. 

Tim Spector: And you're taking vitamins on top of that, do you? 

Bryan Johnson: Yeah. I take about 40 pills a day. And they're what we hope, I guess, what we think the evidence says are the best.

We do calcium, alpha-ketoglutarate, taurine, lysine. We do NR, CS, basically, we tried to scour the evidence to say what things cannot be achieved in dietary intake and how do we supplement those? 

Tim Spector: So you look at what you're eating and you say, what might we be missing from those foods?

Bryan Johnson: Exactly. 

Tim Spector: And you supplement with these ones. 

Bryan Johnson: Yeah. So we try to create as perfect of a diet as possible. Or we say every calorie has to fight for its life. 

Nothing makes its way into my body that is a nice to have, or that is cool or just tastes good. It has to have robust evidence that is a food type that has robust effects inside the body.

We think that there's no diet that can satisfy the body's needs, especially if you want to be on the edge of anti-aging. And so we try to supplement all the things you can't get through diet or improper amounts. And then we measure everything to say, are these levels on point or do we adjust something?

Tim Spector: And do you have super amounts of them? Because I mean, a lot of people like these vitamin C infusions and things like that, thinking that more is always better. Do you believe that? 

Bryan Johnson: Yeah. I mean, most things in the evidence show it's a U-shaped curve. And so you want to nail the exact amount and not anymore.

That's why we measure everything so extensively, is we want to peg the absolute correct number and not move from it. 

Jonathan Wolf: And so how many additional vitamins and different supplements are you putting on top of that food base diet that you were describing?

Bryan Johnson: About 40.

Jonathan Wolf: Forty every day? 

Bryan Johnson: Yeah.

Jonathan Wolf: So your pill cupboard is the size of my room. 

Bryan Johnson: Yeah. I was at a hundred, but we've condensed it quite a bit. 

Tim Spector: And that was just, the evidence for those ones was really weaker, and then…? Because I mean the worry about all taking sake a hundred was they might interact with each other and so they might be negating them. 

Bryan Johnson: Yes we've been very open about this where we were impartial. So something's not working and we just remove it immediately. 

So I've been taking the longevity molecule rapamycin for the past five years, and I think rapamycin probably had the most agreement in the entire field as a good thing.

I was on it for five years and we had done extensive measurements of rapamycin, so I would take it and we'd measure my blood levels two hours post, 24, 48, 72. So we'd look at all my levels of C max and tail curves. But then back in September, we decided to discontinue rapamycin because it was messing with my lipids, with my blood glucose and my resting heart rate and giving me small tissue infections.

So the idea was we knew there were trade-offs, but we didn't know. We thought maybe it's worth it, but we just said, we don't think it's worth it. And we stopped it.

And then it was funny a month later, that paper came out at Yale showing that rapamycin on two of the 16 clocks, or I think more maybe, had accelerated the speed of aging.

So it's just a good lesson to always be agile and to be very humble. So we are very, very humble. We think we probably don't know most things, but the power is in able to measure it continually. So we caught this one.

But still, it's definitely really dangerous to be overconfident.

Jonathan Wolf: So Tim, I'm really curious as I'm listening to this, your view, right? One of the world's experts on nutrition and you've been looking a lot in your background about sort of how this ties into longevity. 

Are there any areas as you listen to that that you would either suggest Bryan should be exploring or things where you're saying, well actually a bit like this example you were giving where that's a super drug and then five years later you're like, Oh my God, it's causing me all of these, it's damaging me, I've got to stop? 

What would you be saying?

Tim Spector: As I was exploring, I believe that some of these vitamins, if you take too much of them, can have negative effects on your body.

Many people around the world are just going crazy and taking as much of it as they can. And that's the whole nutrient vitamin business is selling you those.

So I'd be concerned that, for example, you might be taking too much calcium because too much calcium causes heart disease. But it sounds like you've already thought of a lot of those angles. 

It's good to see that having started rifamycin, realized that it's actually harmful. Some of these things are actually harmful to individuals.

So, there might be some people that benefit, but other people, not. It's very personalized. 

Jonathan Wolf: And Tim, you're often pretty skeptical, I think, about vitamins and these other ultra-processed chemicals rather than getting this through whole food. What would you…

Tim Spector: I would be looking to see if these supplements that Bryan was taking couldn't be got from other foods or increasing the diversity of other foods he was taking. Because that's the natural way that we've evolved to use these substances. 

So I have a general disquiet about taking some of these nutrients as in the chemical form, rather than in the pure form. That's because we think the body might react differently to them. 

But the example with calcium, I gave you, if you have calcium as a chemical, it's in a large amount, it goes in a big amount in the body. It may not be absorbed the same way and therefore ends up being deposited in different bits of the body than if you took it in spring water or something, where it would be much more evenly distributed in the way that our bodies evolved to do that. 

So as a general principle, we're still very unclear about how these vitamins are actually working and maybe just as many negative effects as there are positive ones.

So I'd be looking to say, well, can you diversify even more? At ZOE, we really believe in plant diversity as being one of the key elements to having the most different species of microbe, which then gives you the natural chemicals, and the natural vitamins. But you know, I'd love to discuss this further.

Jonathan Wolf: And what about Bryan's diet in terms of the food that he was describing? What were your thoughts about that? 

Tim Spector: That seems a healthy diet. I would get bored with it. 

I think humans do like a bit of diversity and get pleasure from it. And so I always get pleasure from varying my diet, trying to get different things on my plate. And so that would be my one element.

Has it taken some of the pleasure out of eating because some of the pleasure of eating could well be one of these key human factors that makes us want to live longer, rather than shorter? So I'd love to hear Bryan's take on whether you really enjoy your food.

Bryan Johnson: I love it. I've never loved my food more. I absolutely love it. 

It's both that and I feel liberated from needing to decide what to eat. That whole process of going to a restaurant, looking at a menu and parsing through and not knowing where the food's coming from, or do you eat the croissant or do you have the small bit of ice cream?

I just feel liberated to not deal with that emotional wear and tear. My objective is to be the first model of a human that doesn't die. 

I did this exercise a couple of years ago where I did this thought experiment where I said, so when you came here today, you probably put my address in your phone and you probably followed the navigation that took you here.

You probably didn't study the streets. You probably didn't look at the traffic patterns. It was entirely algorithmic because you trust that their data acquisition was much better than navigation. 

And I wondered if the same was true. I thought, can I basically have a navigation algorithm for my diet?

Can we take all my measurements? Can we plug it into a system? Can we look at the scientific evidence and just run the algorithm and the algorithm tells me what to eat? And can I just remove my mind from the entire process? 

That's what we've tried to do. I know that the normal way that humans do this is you navigate the world and you're making spontaneous decisions on what you eat, when, and where, and have this variety of experience, totally understand that.

And I'm saying that probably what's going to happen is algorithms are going through all the work for us. We'll have more data about our bodies. It will be fed into a system that we'll just have this closed loop system. It may feel like we're making a choice, but ultimately it's going to be much better at managing our health than we will be.

So I'm trying to be an early prototype of this is what it's going to be to be human. 

Jonathan Wolf: I know we're running out of time, I'd like to finish with one final question if that's all right.

I think that both what you're doing with Blueprint and ZOE, they're both trying to shape the future of health and I was just curious if I can almost have one sentence from each of you. What do you think the personal health practices are going to look like in 30 years' time?

Tim Spector: I think personalization is going to be everything. So we're just seeing the dawn of home testing, home blood draws, and doing the ZOE kit at home now, which was so unthinkable 10 years ago.

I think we're going to have smart toilets. I'm a big fan that a lot of your body's health can be told from what's going on inside your gut and your gut microbes and the chemicals they're producing.

So I think we'll all be having super smart toilets that will tell us what the chemicals of our microbes are producing and what we should be eating during the next week to balance that out and what our risks of diseases, et cetera are. 

I think a combination of blood, urine, and stool testing at your home is going to be a regular feature and we'll be titrating things, accordingly in the homes, you know, like this that have all the gadgets, certainly.

Bryan Johnson: I think it will be like what's happened in the stock market. Where it used to be the case that an investor would read up on a company, read all the reports, study the industry and decide on that stock. 

And now a substantial amount of trading in the market is these high-frequency trading systems where these algorithms are ingesting gigantic amounts of data. They're seeing patterns that humans cannot, and they're executing transactions at the millisecond scale, faster than any human can make a decision and beyond the knowledge of any human.

I think these patterns will be very thorough through humans as well. That our health will be managed by a high-frequency trading system. 

Right now we think about these things and very like we're a stock picker for our body. Like we say, this food is good in my body. It's just like picking a stock. Whereas we're much more granular about the molecular structure of a given thing. And the data will be acquired from our body. It will go into an algorithm and it will start trading on our behalf at the molecular level. 

So I think the majority of our health decisions will be gone. We won't even think about it and it will just be part of systems. And I think that's six years from now. I think it's entirely reasonable that we'll have early prototypes by then. 

And if I could leave your viewers with a suggestion of five habits for sleep, 

Jonathan Wolf: Go for it 

Bryan Johnson: I’ll make this very actionable. So my authority on this is I achieved the best sleep score in human history, a month of perfect sleep. So here's five things that everybody can do.

One is to reframe your identity, that you are a professional sleeper. Right now our cultural relationship with sleep is we sleep when it's convenient when we're finished with our show, when we're done with the outing. We sleep at odd hours. So you are a professional sleeper and take it as seriously as you do your profession. 

Number two is to have your final meal of the day at least two hours before bedtime. I have my final meal of the day, nine hours before my bedtime. I tested a few hundred different experiments at different times, and different foods to experiment with this.

I find that when I do that, my resting heart rate goes down by about 20%. So it right now is about 44 when I go to bed and that gives me a perfect night's sleep. So eat earlier and lighter and experiment, try to find the right time for you. 

Three is consistency. So when I was going to bed, when I was doing this experiment, I was in bed at the same time, plus or minus one minute. It was remarkable how powerful my body was in putting itself to sleep. If you get the body rhythm and consistency, it will be a superpower for you.

Four is light. So try to turn down blues in the house, turn off screens, you know, an hour or so before bed. If you can have an amber light or red light, the best. So light is very important. 

And then five is a wind-down routine. And so this is really important. So at 8.30, I go to bed, and at 7.30, I begin my nighttime wind-down routine. And I do a self-talk where 7.30 arrives and then the moment I start nighttime mode I'll have a thought like, Hey, Bryan, I have a new idea for a new thing I can do, or, Hey,  Bryan, you said something today that probably offended the person. They probably hate you and you were not worried about it. 

So I can say, thank you ambitious Bryan for reminding me that this is a good idea. We appreciate you, you're doing good work in life. Or thank you anxious  Bryan for identifying that we really messed up in that conversation and said that rude thing. I promise I'll take care of this tomorrow. You see, I'm going to write this thing down right now. 

But you're doing this because you're trying to calm your nervous system to say, we are now in sleep mode. We're going to calm ourselves down and we're going to sleep. Otherwise, if you don't, and you take this energy into the bed when your head is a pillow, you then ruminate on all these thoughts, good, bad, and ugly.

And then you wake up the same thing, you can't go back there because now you ruminate on these thoughts. And so the wind-down routine is probably the most powerful because you're really setting yourself up for a great night's sleep. 

But to do that, you have to take it seriously, which is back to your identity.

So do those five things and I think it will change your life more than anything in the entire world. And when you sleep well, you're going to want to exercise. And when you exercise, you want to eat well. And it's just a really positive virtuous loop. 

Jonathan Wolf: I absolutely love that. I also think that I definitely have a competitive Jonathan and an anxious Jonathan. So I love this idea of trying to put them to bed before I go to sleep on the way. So I'm definitely going to take that away. 

I am curious what you do with a five-year-old child or a spouse who doesn't necessarily want to follow all of your rules. Have you got a solution for that? 

Bryan Johnson: Two suggestions. One is to have a family meeting and identify that you are a family that prioritizes sleep. 

So I have three children and if you make it a family priority, we go to bed at this time, we have dinners at certain times, and nobody gets up from their bed at night time. Nobody ever wakes up anyone as a rule, for example, then you can establish sleep hygiene as a family.

And number two, for your child and your spouse, create a star chart and give them a one-star review when they deviate from family culture. 

So if you're a five-year-old wakes you up at night, give them a one-star review, and put it on the wall. One star nobody likes one-star reviews and that includes your partner as well. So if your partner wakes you up at night or, you know, is going to bed later than expected, give them a one-star review. 

Jonathan Wolf: Well, you run your family in a tough way. I feel like if I gave any one-star reviews at home, I'd be out on my ear outside the front door, but I'll run that by Justine and see how she feels.

Bryan Johnson: When people are well rested, we are more cheerful, we are more agreeable, we are more fun, we are more pleasant, and when we are tired, we are grumpy, we are argumentative, we are short, so everybody in the family has an interest in having high-quality sleep. 

Jonathan Wolf: I think it's completely logical and like many things that you're talking about, like bad habits, right? So much of our life is built to make that hard, right? 

You think about it, the phone is designed to make sure you can't put it down, right? The TV on Netflix is designed to automatically show you the next episode. The food that we're surrounded by is ultra-processed food that clever scientists have built to make you want to eat more.

So this is hard, isn't it? 

Bryan Johnson: You will rise to the level of your habits, not your goals. So these are all about building life systems. It's not about decision-making. It's about systems that allow you to live your best life. 

Jonathan Wolf: And does that mean that because it's sort of a regular habit, you don't need to think about it so much and therefore you're more resistant to the outside?

Bryan Johnson: I mean, do you eat this bad thing or not? It's already decided for you. Do you go to bed at your bedtime? Yes or no. 

So you have to pre-decide all these things, so you don't have to grapple with them in the moment. A lot of people will say that sounds so boring. So it takes away my choice. 

But if you don't, you end up losing the majority of those decisions and you end up living in a life that is less than what you want.

 Now you can rationalize it and say it's like whatever, but generally speaking, do I have anyone in my life who complains to me that they feel too good that they've never said, you know what, God damn it, I just feel great and it just sucks.

It is generally a feeling that we really appreciate feeling great. And so these things are in our best interest. We really do want them. And it's so easy to slip into the rationalization, but we all want to be our best self. 

Jonathan Wolf: I have to say that if I think about that, just simply as saying locking yourself into good things, I absolutely buy that.

I don't have that much willpower. So for example, I booked three sessions a week with my trainer because, because the trainer’s there, I will exercise. If I don't have the trainer, I'll be like, Oh, I'll do some more work. So it doesn't happen. 

And similarly in the food, honestly, people tease me about the food in the house. So basically I tried to make sure there isn't any bad, we don't like to say bad food at ZOE, but let's say food that scores really badly for me. And I really, and I would eat lots of. I try to make sure it's not in the house because then I'll just eat something else. 

I'm nothing like as controlled as you. There is dark chocolate in the house and fruit and all that. But the point is, if I compare that with what I would have had in the house 10 years ago, it was transformed just because basically I'm taking away my own willpower. 

So you're sort of saying take that to the next level with sleep and almost try and make your family co-conspirators. So will your wife give you a one-star review or are you so controlled that's not even…

Bryan Johnson: My son and I, definitely have family systems and we adhere to them. And when we don't, we hold each other accountable. So I definitely am in a family environment. We all agree on systems. 

Jonathan Wolf: That's fascinating. Thank you both.

I'd like to do a quick summary if that's all right. I'd start by saying that actually, Tim and  Bryan agree a lot more than I expected at the beginning of this show. And in some sense, right there at the end, you're talking about the future is personalized health based on lots of data.

It's really interesting actually how much that converges because I think the starting point is very different. 

Bryan, you're basically saying you want to be the first human to not die. That sounds like to me, it's this crazy out-there idea. I know that that is not where Tim wants to go, but it's really interesting how much this converges.

You talked about the fact that basically, you are fitter than a 16-year-old because of everything you're doing, which is amazing. And every decision you make is an experiment, but that's true for everyone on earth. So it's just for you it's explicit, for everyone else they're not thinking about it. 

So if we think about you as almost forging this path, it can make it a lot easier for everybody else that everything you're doing is based upon your best ability to analyze the best science.

In a sense, you're trying to go after the same thing that Tim would talk about. I want to avoid all the issues that come with obesity. I want to have everything, that's a really strong cardiovascular system, but then I can measure a lot more stuff than most doctors will do because I'm putting a lot of money against it and these most advanced people.

So you don't just take blood, you track your erections, right?  That's definitely a next level. Tim, we have definitely not put that in the ZOE kit. 

You then said a lot of what you have to do actually is quite clear, like when you come down to it, it's not so fancy anymore. Sleep was your number one exercise, a good diet, and drop the bad habits. It's actually very similar to lots of the other podcasts we talk about. 

I think the thing that really strikes me is the level of control that you apply to your life. So very few people can have that level of self-control, and it means that you're carrying this out to this optimized level.

And then finally, I think interestingly when we look through to diet, your diet is quite similar to a lot of the things that we talk about with ZOE. So, you're vegan, it's plant-centric, there's a lot of extra virgin olive oil, you know, all these nuts and berries.

You are then adding a lot of vitamins, and I can see that that's the one area maybe where Tim is more skeptical. I think you're also willing to take risks, right, when you're talking about some of these drugs that you take that then turn out to be negative. I think Tim is always saying, for example, with the vitamins and calcium, that this could be harmful. 

But fundamentally, you're like this test pilot, that's how I'm now thinking of you, shooting off in these dangerous rockets. Could make it to the moon, but you're willing to take some risks that it might flame out and we get to watch and learn everything, which in many ways, I think is a very generous contribution to the rest of us.

So thank you.

Bryan Johnson: You're welcome.