Lifespan and Ageless
Lots of books claim to be 'life changing' in the blurb. Very few of them deliver on that promise. Up until recently I'd say that Richard Dawkin's 'The God Delusion' was probably the most influential book on me. Years after I first read it I had the chance to have my copy signed by him, and told Richard that "this is the book that made me give up religion", which naturally he was pleased with. In truth I'd been leaning that way for a while, otherwise I'd never have dared buy a book entitled 'The God Delusion' to begin with. But it was the book that gave me that final push over the line to admit that I was likely more an atheist than anything else.
I often play Youtube videos while I'm doing the washing up, and two months back one suggestion came up on 'Why age? Should we end aging forever'.
It's at this point that I realize that the Brits spell it 'ageing' and the Americans spell it 'aging'. I did change all my spelling in the last entry to the British version, but it looks like I've used the American spelling for most of my entries. So forgive my inconsistencies as I can't be bothered to change all of them to one spelling now.
But back to the video. I was intrigued, and quickly searched out several other videos on the topic. David Sinclair was a name that came up frequently, and I bought his book Lifespan: Why we age - and why we don't have to.
I studied Biology at university, and promptly forgot nearly all of it. It included modules on biochemistry and genetics that I'm embarassed to admit I may as well not have done for all I remember them. So I'll attempt to explain the main points, but if my explanations come out as garbled, then please check out some original sources.
First off, what causes aging? Remarkably, it's only in the past few decades that we've began to have any clue at all. Originally it was suspected that DNA damage caused mutations in our cells. But that's not thought to be exactly true any more. If the DNA in older animals cells were all damaged, then all clones would be born old, which isn't the case.
Now it's thought to be primarily based on epigenetic facors, also known as 'the information theory of aging'. If DNA is the words of the cell, then epigenetics is the way in which they are read. All cells (with the exception of red blood calls which contain no DNA and sperm and eggs that carry half the usual amount) contain our full set of chromosomes. And yet they differ hugely in how they operate, from skin to muscle to brain cells. The reason they are widely different despite carrying the same information is because of epigentic processes that choose what genes in the cell to turn on or off. Is this making any sense? Here, if you have five minutes for a more detailed explanation let a profesional explain it to you.
This process becomes more disfunctional with time, meaning that cells no longer differentiate properly, leading to the gradual degradation of all manner of organs and processes.
But how to keep the aging process at bay? Let's start with the obvious and least controversial points that any doctor would tell you. Exercise regularly. Eat more fruit, nuts and vegetables and less meat and dairy. Don't drink a lot of alcohol. Definitely don't smoke.
A more recent find is that a family of proteins known as sirtuins help to repair and retain these epigentic factors, and that a (limited!) degree of stress helps to activate them. It's been known for a while that limiting calorific intake in numerous species of animals helps to prolong their lifespan, and there's some evidence to suggest fasting in humans does the same. One theory is that in order to keep your sirtuins active in repairing the epigenetic damage, allow your body to feel stress but not so much stress that it damages it. Exercise to the point of breaking a sweat but not too utter exhaustion, get cold to the point of being chilly but not hypothermia, and limit your food intake to the point of hunger but not malnutrition.
Part of longevity is just the sheer luck, with several longevity genes identified in humans. That combined with a healthy lifestyle can help you live towards the upper end of the human lifespan. The longest reliably recorded human lifespan was 122 years and 164 days. It's doubtful anyone will live a few months beyond that with just lifestyle choices and lucky genes alone.
Is that the end of the story? Well hopefully not. With various medical interventions we may be able to treat the disease of aging. At which point many people will object that 'aging isn't a disease, it's a natural process.' But why not both?
Aging is a condition that causes fraility, an increased susceptibility to infection and injury, white or thinning hair, wrinkles and a sagging of the skin. It's the main risk factor for cancer, heart disease, alzheimer's, strokes, arthritis and hundreds of other debilitating and deadly conditions. Given enough time it is always fatal. If this affected only 10% of the population we'd consider it a disease for sure. But 100% of people and we no longer think that way.
Billions is spent trying to fight all manner of age related diseases. But many in the longevity community argue that we have this backward. We should combat the mother of all diseases itself, aging.
Consider cancer. A cure for cancer would be the holy grail of the medical world. Instant nobel prizes all round. Yet if cancer were eliminated worldwide tomorrow the affect on global lifespan would be an increase of three years. Eliminate all heart disease and you'd increase it by two years. An impressive feat, but ultimately focusing on the individual diseases associated with aging is a 'whack a mole' approach. Cure cancer and that same person dies of a stroke, a heart attack or Alzheimers a few years later. Cure aging and you get most of the world's ailments eliminated for free.
At this point you might be thinking curing aging would be nice... but it's just not possible. Not long ago I'd have likely said the same thing. But in the past few years scientists have made not only great strides in understanding aging. They've made some significant steps in fighting it.
Now to be clear there is currently no treatment clinically proven to extend human life, but there are numerous promising treatments and experiments that hint that we're approaching a time when we will be.
One of the most promising is cell rejuvination, a technique that literally resets cells to a younger state using molecules known as Yamanaka factors. Using this mice in the lab have not just had their aging slowed, in one experiment their age showed signs of being reversed! Using a similar technique, scientists in Sinclair's lab were able to actually restore the sight to previously blind mice by restoring their cells to a younger state!
https://www.nature.com/articles/d41586-020-03439-2
It's worth mentioning that David Sinclair can be a divisive figure. He is a Professor of Genetics at Harvard, and certainly no woo peddler. But there are times he's been accused of overhyping the significance of his findings, which I think is a fair critisism. But on the whole I'd say there's no doubt that Sinclair's lab have been behind some hugely significant findings in aging research, and that Lifespan is a very worthwhile read.
Phew, this post is getting pretty long, and I still have another book to introduce to you, Ageless: The New Science of Getting Older Without Getting Old by Andrew Steele. Usually after finishing a book I like to read something totally different. Mix up my fiction and my nonfiction. But I was engrossed in the subject of anti aging research, so bought Ageless a few days after finishing Lifespan.
Unlike Sinclair, who is undertaking research himself, Andrew Steele works more as a science journalist, and Ageless details the hallmarks of aging, the history of aging research, the evolution of why many animals likely came to age in the first place, the huge variety of lifespans in the natural world, and a broad overview of what is being done around the world in an attempt to cure aging. There's a whole slew of his videos that I could link to, but I think this one does a great job of introducing the themes of his book to beginners. If you only click on one of the many links I'm including, make it this one!
One thing that any of the scientists in the lonevity field will tell you is that it's not about extending lifespan so much as extending healthspan. An increase in healthspan means more time spent enjoying life.
I'd never heard of the epigenetic clock before, which was intriguing. Previously any study in human longevity had to, rather morbidly, wait for all its participants to die before all the results were in, a process that could take decades. The epigenetic clock is a way to measure biomarkers of aging, based on DNA methylation levels, so that it's possible to tell if treatments are speeding up or slowing down the aging process, or even reversing it, without waiting around for the test subject to die.
https://en.wikipedia.org/wiki/Epigenetic_clock
Both books mention a number of experiements with mice. Like most people, I don't exactly love experimentation on animals. Peter Singer's Animal Liberation has a grim record of some of the most unpleasant, as well as unnecesary, animal experiments. But when the knowledge being gained can lead to improved medicines, I'd say it's the lesser of two evils.
I once went to a debate on animal experimentation, and one of the panelists noted how it was odd that experiments involving animals were a lot more of an emotive issue than farming animals for meat. Animal experimentation may not be pleasant, but it can lead to medical breakthroughs that go on benefitting humans indefinitely. Eat some chicken, of which 70 billion are killed every year, and you'll be hungry again in a few hours. And you could so easily have eaten something else that didn't mean an animal had to die.
As I'm sure you can tell I'm pretty excited by all this stuff, and have been eating up every article and youtube video I can find on the subject. But both myself and you dear reader will need a break, so I'll be posting more on how I feel about it in a couple of days.
I often play Youtube videos while I'm doing the washing up, and two months back one suggestion came up on 'Why age? Should we end aging forever'.
Click to viewIt's at this point that I realize that the Brits spell it 'ageing' and the Americans spell it 'aging'. I did change all my spelling in the last entry to the British version, but it looks like I've used the American spelling for most of my entries. So forgive my inconsistencies as I can't be bothered to change all of them to one spelling now.
But back to the video. I was intrigued, and quickly searched out several other videos on the topic. David Sinclair was a name that came up frequently, and I bought his book Lifespan: Why we age - and why we don't have to.
I studied Biology at university, and promptly forgot nearly all of it. It included modules on biochemistry and genetics that I'm embarassed to admit I may as well not have done for all I remember them. So I'll attempt to explain the main points, but if my explanations come out as garbled, then please check out some original sources.
First off, what causes aging? Remarkably, it's only in the past few decades that we've began to have any clue at all. Originally it was suspected that DNA damage caused mutations in our cells. But that's not thought to be exactly true any more. If the DNA in older animals cells were all damaged, then all clones would be born old, which isn't the case.
Now it's thought to be primarily based on epigenetic facors, also known as 'the information theory of aging'. If DNA is the words of the cell, then epigenetics is the way in which they are read. All cells (with the exception of red blood calls which contain no DNA and sperm and eggs that carry half the usual amount) contain our full set of chromosomes. And yet they differ hugely in how they operate, from skin to muscle to brain cells. The reason they are widely different despite carrying the same information is because of epigentic processes that choose what genes in the cell to turn on or off. Is this making any sense? Here, if you have five minutes for a more detailed explanation let a profesional explain it to you.
This process becomes more disfunctional with time, meaning that cells no longer differentiate properly, leading to the gradual degradation of all manner of organs and processes.
But how to keep the aging process at bay? Let's start with the obvious and least controversial points that any doctor would tell you. Exercise regularly. Eat more fruit, nuts and vegetables and less meat and dairy. Don't drink a lot of alcohol. Definitely don't smoke.
A more recent find is that a family of proteins known as sirtuins help to repair and retain these epigentic factors, and that a (limited!) degree of stress helps to activate them. It's been known for a while that limiting calorific intake in numerous species of animals helps to prolong their lifespan, and there's some evidence to suggest fasting in humans does the same. One theory is that in order to keep your sirtuins active in repairing the epigenetic damage, allow your body to feel stress but not so much stress that it damages it. Exercise to the point of breaking a sweat but not too utter exhaustion, get cold to the point of being chilly but not hypothermia, and limit your food intake to the point of hunger but not malnutrition.
Part of longevity is just the sheer luck, with several longevity genes identified in humans. That combined with a healthy lifestyle can help you live towards the upper end of the human lifespan. The longest reliably recorded human lifespan was 122 years and 164 days. It's doubtful anyone will live a few months beyond that with just lifestyle choices and lucky genes alone.
Is that the end of the story? Well hopefully not. With various medical interventions we may be able to treat the disease of aging. At which point many people will object that 'aging isn't a disease, it's a natural process.' But why not both?
Aging is a condition that causes fraility, an increased susceptibility to infection and injury, white or thinning hair, wrinkles and a sagging of the skin. It's the main risk factor for cancer, heart disease, alzheimer's, strokes, arthritis and hundreds of other debilitating and deadly conditions. Given enough time it is always fatal. If this affected only 10% of the population we'd consider it a disease for sure. But 100% of people and we no longer think that way.
Billions is spent trying to fight all manner of age related diseases. But many in the longevity community argue that we have this backward. We should combat the mother of all diseases itself, aging.
Consider cancer. A cure for cancer would be the holy grail of the medical world. Instant nobel prizes all round. Yet if cancer were eliminated worldwide tomorrow the affect on global lifespan would be an increase of three years. Eliminate all heart disease and you'd increase it by two years. An impressive feat, but ultimately focusing on the individual diseases associated with aging is a 'whack a mole' approach. Cure cancer and that same person dies of a stroke, a heart attack or Alzheimers a few years later. Cure aging and you get most of the world's ailments eliminated for free.
At this point you might be thinking curing aging would be nice... but it's just not possible. Not long ago I'd have likely said the same thing. But in the past few years scientists have made not only great strides in understanding aging. They've made some significant steps in fighting it.
Now to be clear there is currently no treatment clinically proven to extend human life, but there are numerous promising treatments and experiments that hint that we're approaching a time when we will be.
One of the most promising is cell rejuvination, a technique that literally resets cells to a younger state using molecules known as Yamanaka factors. Using this mice in the lab have not just had their aging slowed, in one experiment their age showed signs of being reversed! Using a similar technique, scientists in Sinclair's lab were able to actually restore the sight to previously blind mice by restoring their cells to a younger state!
https://www.nature.com/articles/d41586-020-03439-2
It's worth mentioning that David Sinclair can be a divisive figure. He is a Professor of Genetics at Harvard, and certainly no woo peddler. But there are times he's been accused of overhyping the significance of his findings, which I think is a fair critisism. But on the whole I'd say there's no doubt that Sinclair's lab have been behind some hugely significant findings in aging research, and that Lifespan is a very worthwhile read.
Phew, this post is getting pretty long, and I still have another book to introduce to you, Ageless: The New Science of Getting Older Without Getting Old by Andrew Steele. Usually after finishing a book I like to read something totally different. Mix up my fiction and my nonfiction. But I was engrossed in the subject of anti aging research, so bought Ageless a few days after finishing Lifespan.
Unlike Sinclair, who is undertaking research himself, Andrew Steele works more as a science journalist, and Ageless details the hallmarks of aging, the history of aging research, the evolution of why many animals likely came to age in the first place, the huge variety of lifespans in the natural world, and a broad overview of what is being done around the world in an attempt to cure aging. There's a whole slew of his videos that I could link to, but I think this one does a great job of introducing the themes of his book to beginners. If you only click on one of the many links I'm including, make it this one!
One thing that any of the scientists in the lonevity field will tell you is that it's not about extending lifespan so much as extending healthspan. An increase in healthspan means more time spent enjoying life.
I'd never heard of the epigenetic clock before, which was intriguing. Previously any study in human longevity had to, rather morbidly, wait for all its participants to die before all the results were in, a process that could take decades. The epigenetic clock is a way to measure biomarkers of aging, based on DNA methylation levels, so that it's possible to tell if treatments are speeding up or slowing down the aging process, or even reversing it, without waiting around for the test subject to die.
https://en.wikipedia.org/wiki/Epigenetic_clock
Both books mention a number of experiements with mice. Like most people, I don't exactly love experimentation on animals. Peter Singer's Animal Liberation has a grim record of some of the most unpleasant, as well as unnecesary, animal experiments. But when the knowledge being gained can lead to improved medicines, I'd say it's the lesser of two evils.
I once went to a debate on animal experimentation, and one of the panelists noted how it was odd that experiments involving animals were a lot more of an emotive issue than farming animals for meat. Animal experimentation may not be pleasant, but it can lead to medical breakthroughs that go on benefitting humans indefinitely. Eat some chicken, of which 70 billion are killed every year, and you'll be hungry again in a few hours. And you could so easily have eaten something else that didn't mean an animal had to die.
As I'm sure you can tell I'm pretty excited by all this stuff, and have been eating up every article and youtube video I can find on the subject. But both myself and you dear reader will need a break, so I'll be posting more on how I feel about it in a couple of days.