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On some podcast a longevity doctor asked the host to estimate how much longer the average person would live if we eliminated/cured cancer. The answer was about

by tacon 2y ago

On some podcast a longevity doctor asked the host to estimate how much longer the average person would live if we eliminated/cured cancer. The answer was about three years. Eliminate heart disease? Another three years. Eliminate both? About five years. https://en.wikipedia.org/wiki/Memento_mori https://en.wikipedia.org/wiki/Memento_mori

A_D_E_P_T 2y ago
Was this a well-corroborated and fact-based opinion, or was it off-the-cuff and handwavey? Podcast answers aren't always totally reliable. But you mention "the average person," which is really the crux of the matter. Cancer strikes perfectly average people, oftentimes in their 30s or 40s, and hands down death sentences at random. A bad roll of the dice. A stray cosmic ray hit a dividing cell. Who knows? That is what is scary. Eliminating cancer may perhaps only increase the average lifespan by three years -- though I have my doubts -- but what's much more important is that it would cut down tremendously the number of premature and random-seeming deaths in the prime of life.
- Theodores 2y ago
  The thing is that we are led to believe that cancer just strikes at random, and anecdotally we know of someone that never smoked to get lung cancer that spread everywhere to strike them dead. Yet we also know it is not quite like that. If you smoke, drink, make sculptures out of asbestos dust, eat processed meats, shoot depleted uranium rounds down at the range and work with radium in a gun sight factory then you probably have stacked the odds. Now imagine you have an identical twin, maybe not cojoined, but living with the exact same stacked odds. However, you eat a strict diet of highly processed foods and only play tiddlywinks for physical activity. Meanwhile, your twin rides eats a strict diet that is mostly whole food, plant based and gets a lot of physical activity due to a passion for dancing. One of you is going to be likely to suffer a cardiovascular event before the other and that same person is going to run the risk of catching cancer first. Now we all know that eating processed foods, maybe with the exception of processed meat, isn't going to 'give you cancer' and neither is playing tiddlywinks. Equally, a few extra antioxidants and a bit of fibre from eating a few more carrots isn't going to spare you from cancer, neither is dancing for that matter. Nonetheless, cardiovascular and gut health is important for reducing cancer risks. I say this with anecdotal evidence provided by a car dependent relative that chose not to eat a fibre rich diet and now has cancers that I would not wish on anyone, with his digestive tract having to be trimmed from the far end due to cancer. Because he took the medical route with meaty pies and moderate alcohol levels, his life might only be cut short by three years. However, by then, there will be two decades of extreme medical interventions and a smorgasbord of medications that have to be taken daily. Lifespan is not as important as healthspan and there is much we can do through diet and physical activity to maximise healthspan. The trouble with my relative is that advice to go absolutely teetotal, stay off the processed meats and to eat fibre (as in vegetables) was not a message that was well received. This advice is in line with WHO recommendations but this can be simply ignored once lifestyle choices have been decided on.
  - A_D_E_P_T 2y ago
    > Yet we also know it is not quite like that. Oh, come on. Even if you're correct and cancer is not completely random but rather has clear causative factors, a lot of those factors -- perhaps the majority -- are uncontrollable. Radon exposure. Naturally occurring radioactive isotopes or beryllium in your vegetables or water. That virus you fought off a few years ago. That course of cyclosporine you once took. That cosmic ray from the Andromeda galaxy that happened to hit you and scramble some DNA. Many, many other factors. Cancer strikes in ways that seem truly random because many or most of its causative factors have absolutely nothing to do with lifestyle choices.
    - freedomben 2y ago
      Exactly. There are definitely people who lead higher risk lives by having exposure to carcinogens, but even that has some randomness to it. I had a family friend that smoked like a chimney his entire life, and died in his late '80s with tar-filled but cancer-free lungs. Another was an x-ray tech in the earlier days before they took nearly as many precautions as they do now to protect the technicians. No cancer. Contrast this with some aunts and uncles who lived relatively clean lives, and still ended up dying of different cancers. Sure, I don't doubt there is a cause if we dig deep into it, but there's still some randomness.
    - commodoreboxer 2y ago
      Eh, it's still a numbers game. Changing your chances of contracting terminal cancer in the next 5 years from 1% to 0.5% is still significant. In this case, the specific percentages are all the significance. When a lot of the factors are controllable and a lot of them are uncontrollable, the most reasonable question is "How much do the controllable factors actually change the odds?"
      - A_D_E_P_T 2y ago
        > Changing your chances of contracting terminal cancer in the next 5 years from 1% to 0.5% is still significant. Short of quitting smoking, there's almost no way to do that, because you don't know what the factors are or how they're weighed & influenced by individual genetic, immune, and metabolic factors. > "How much do the controllable factors actually change the odds?" Not only does nobody know, nobody has the foggiest notion. I've never seen a relevant population-wide observational study that wasn't so full of methodological flaws that you could spend hours picking apart its defects. Of course we know that there's a set of factors associated with the development of cancer -- like, e.g., long-term exposure to polonium in drinking water -- but there's also a large set of factors that nobody is aware of or which can never be controlled for. To use only the first set -- the set of what we know and can control for -- to accurately estimate the odds of contracting cancer within the next five years is impossible.
melling 2y ago
Maybe looking at the average is the wrong thing to do. People who die from cancer can be robbed of a lot of years. A couple of other recent cancer deaths I saw on HN: Walter Ehmer died at 58 https://news.ycombinator.com/item?id=41490388 https://news.ycombinator.com/item?id=41490388 Jake Seliger was also known on HN died around 40: https://news.ycombinator.com/item?id=41201555 https://news.ycombinator.com/item?id=41201555
shepherdjerred 2y ago
This reminds me of a video I saw on HN yesterday: https://www.youtube.com/watch?v=CJkWS4t4l0k https://www.youtube.com/watch?v=CJkWS4t4l0k
w3gS34k354K7978 2y ago
I find those estimates believable in a narrow interpretation of the question - i.e. if we solve cancer but change nothing else. I would expect a longevity M.D. to understand the spirit of the question and answer accordingly, though. I'm curious which podcast / doc this was? It's true that solving cancer, heart disease, and even all other similarly deadly diseases, would not automatically mean humans living indefinitely, because there's still cellular senescence to contend with. Fortunately, we've effectively solved senescence (or at least it seems we're well on our way). Check out the picture of the twin mice from David Sinclair's lab (https://sinclair.hms.harvard.edu/research https://sinclair.hms.harvard.edu/research) - it's hard to believe the two mice were born at the same time... And if I recall correctly, they didn't even do any sort of telomere modification in that study either... Don't quote me on that. But telomeres are another potent avenue towards >10x extension of life span, and also as it turns out, fairly trivial to lengthen and thereby allow a cell to continue mitosis indefinitely. The problem to solve is cancer, though. Telomeres limit the number of times a cell can divide by design, and seemingly the purpose of limiting division in the first place is to mitigate risk of developing cancers.
Panzer04 2y ago
This sounds surprisingly short. Surely the average person with cancer isnt going to live just three additional years? Went and did a brief lookup (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6710558/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6710558/) - life expectancy is reduced by at least 3 years, even for the oldest patients, and increases significantly as age at diagnosis goes down. I suppose from the perspective of an 80 year old, curing cancer would in theory increase life expectancies by ~ 3 years, though I wonder how many people die of "old age" but have an undiagnosed cancer of some form contributing.
- pessimizer 2y ago
  Most people don't have cancer, so the average lifespan reduction of everyone is going to be quite a bit lower than the average lifespan reduction of people diagnosed with cancer.
- pcwalton 2y ago
  It's because of the Gompertz mortality law [1]--the probability of dying at a certain age is exponential. If you assume that the mortality of each age-related terminal illness itself follows the Gompertz law, then eliminating any one of those illnesses won't affect the overall life expectancy much, because exponential growth is so powerful. Even if we had cures for all age-related diseases except, say, Alzheimer's disease, the fact that Alzheimer's disease mortality also follows the Gompertz law (probably a reasonable assumption) would lead to lifespans not dissimilar from our present ones. Essentially, in order to achieve dramatically longer lifespans, we would need to eliminate, or at least significantly slow, all aging-related causes of death. [1]: https://en.wikipedia.org/wiki/Gompertz%E2%80%93Makeham_law_of_mortality https://en.wikipedia.org/wiki/Gompertz%E2%80%93Makeham_law_o...
- The_Colonel 2y ago
  Keeping the body alive is a low bar. Lost quality-adjusted life years would be a better measure. Many people survive for many years with cancer, but the quality of life drops significantly.
- petercooper 2y ago
adamredwoods 2y ago
Three years would be an amazing amount of precious time with a loved one. I know this.

by tacon 2y ago

A_D_E_P_T 2y ago

Was this a well-corroborated and fact-based opinion, or was it off-the-cuff and handwavey? Podcast answers aren't always totally reliable. But you mention "the average person," which is really the crux of the matter. Cancer strikes perfectly average people, oftentimes in their 30s or 40s, and hands down death sentences at random. A bad roll of the dice. A stray cosmic ray hit a dividing cell. Who knows? That is what is scary. Eliminating cancer may perhaps only increase the average lifespan by three years -- though I have my doubts -- but what's much more important is that it would cut down tremendously the number of premature and random-seeming deaths in the prime of life.

Theodores 2y ago
The thing is that we are led to believe that cancer just strikes at random, and anecdotally we know of someone that never smoked to get lung cancer that spread everywhere to strike them dead. Yet we also know it is not quite like that. If you smoke, drink, make sculptures out of asbestos dust, eat processed meats, shoot depleted uranium rounds down at the range and work with radium in a gun sight factory then you probably have stacked the odds. Now imagine you have an identical twin, maybe not cojoined, but living with the exact same stacked odds. However, you eat a strict diet of highly processed foods and only play tiddlywinks for physical activity. Meanwhile, your twin rides eats a strict diet that is mostly whole food, plant based and gets a lot of physical activity due to a passion for dancing. One of you is going to be likely to suffer a cardiovascular event before the other and that same person is going to run the risk of catching cancer first. Now we all know that eating processed foods, maybe with the exception of processed meat, isn't going to 'give you cancer' and neither is playing tiddlywinks. Equally, a few extra antioxidants and a bit of fibre from eating a few more carrots isn't going to spare you from cancer, neither is dancing for that matter. Nonetheless, cardiovascular and gut health is important for reducing cancer risks. I say this with anecdotal evidence provided by a car dependent relative that chose not to eat a fibre rich diet and now has cancers that I would not wish on anyone, with his digestive tract having to be trimmed from the far end due to cancer. Because he took the medical route with meaty pies and moderate alcohol levels, his life might only be cut short by three years. However, by then, there will be two decades of extreme medical interventions and a smorgasbord of medications that have to be taken daily. Lifespan is not as important as healthspan and there is much we can do through diet and physical activity to maximise healthspan. The trouble with my relative is that advice to go absolutely teetotal, stay off the processed meats and to eat fibre (as in vegetables) was not a message that was well received. This advice is in line with WHO recommendations but this can be simply ignored once lifestyle choices have been decided on.
- A_D_E_P_T 2y ago
  > Yet we also know it is not quite like that. Oh, come on. Even if you're correct and cancer is not completely random but rather has clear causative factors, a lot of those factors -- perhaps the majority -- are uncontrollable. Radon exposure. Naturally occurring radioactive isotopes or beryllium in your vegetables or water. That virus you fought off a few years ago. That course of cyclosporine you once took. That cosmic ray from the Andromeda galaxy that happened to hit you and scramble some DNA. Many, many other factors. Cancer strikes in ways that seem truly random because many or most of its causative factors have absolutely nothing to do with lifestyle choices.
  - freedomben 2y ago
    Exactly. There are definitely people who lead higher risk lives by having exposure to carcinogens, but even that has some randomness to it. I had a family friend that smoked like a chimney his entire life, and died in his late '80s with tar-filled but cancer-free lungs. Another was an x-ray tech in the earlier days before they took nearly as many precautions as they do now to protect the technicians. No cancer. Contrast this with some aunts and uncles who lived relatively clean lives, and still ended up dying of different cancers. Sure, I don't doubt there is a cause if we dig deep into it, but there's still some randomness.
  - commodoreboxer 2y ago
    Eh, it's still a numbers game. Changing your chances of contracting terminal cancer in the next 5 years from 1% to 0.5% is still significant. In this case, the specific percentages are all the significance. When a lot of the factors are controllable and a lot of them are uncontrollable, the most reasonable question is "How much do the controllable factors actually change the odds?"
    - A_D_E_P_T 2y ago
      > Changing your chances of contracting terminal cancer in the next 5 years from 1% to 0.5% is still significant. Short of quitting smoking, there's almost no way to do that, because you don't know what the factors are or how they're weighed & influenced by individual genetic, immune, and metabolic factors. > "How much do the controllable factors actually change the odds?" Not only does nobody know, nobody has the foggiest notion. I've never seen a relevant population-wide observational study that wasn't so full of methodological flaws that you could spend hours picking apart its defects. Of course we know that there's a set of factors associated with the development of cancer -- like, e.g., long-term exposure to polonium in drinking water -- but there's also a large set of factors that nobody is aware of or which can never be controlled for. To use only the first set -- the set of what we know and can control for -- to accurately estimate the odds of contracting cancer within the next five years is impossible.

melling 2y ago

Maybe looking at the average is the wrong thing to do. People who die from cancer can be robbed of a lot of years. A couple of other recent cancer deaths I saw on HN: Walter Ehmer died at 58 https://news.ycombinator.com/item?id=41490388 https://news.ycombinator.com/item?id=41490388 Jake Seliger was also known on HN died around 40: https://news.ycombinator.com/item?id=41201555 https://news.ycombinator.com/item?id=41201555

shepherdjerred 2y ago

This reminds me of a video I saw on HN yesterday: https://www.youtube.com/watch?v=CJkWS4t4l0k https://www.youtube.com/watch?v=CJkWS4t4l0k

w3gS34k354K7978 2y ago

I find those estimates believable in a narrow interpretation of the question - i.e. if we solve cancer but change nothing else. I would expect a longevity M.D. to understand the spirit of the question and answer accordingly, though. I'm curious which podcast / doc this was? It's true that solving cancer, heart disease, and even all other similarly deadly diseases, would not automatically mean humans living indefinitely, because there's still cellular senescence to contend with. Fortunately, we've effectively solved senescence (or at least it seems we're well on our way). Check out the picture of the twin mice from David Sinclair's lab (https://sinclair.hms.harvard.edu/research https://sinclair.hms.harvard.edu/research) - it's hard to believe the two mice were born at the same time... And if I recall correctly, they didn't even do any sort of telomere modification in that study either... Don't quote me on that. But telomeres are another potent avenue towards >10x extension of life span, and also as it turns out, fairly trivial to lengthen and thereby allow a cell to continue mitosis indefinitely. The problem to solve is cancer, though. Telomeres limit the number of times a cell can divide by design, and seemingly the purpose of limiting division in the first place is to mitigate risk of developing cancers.

Panzer04 2y ago

This sounds surprisingly short. Surely the average person with cancer isnt going to live just three additional years? Went and did a brief lookup (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6710558/ https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6710558/) - life expectancy is reduced by at least 3 years, even for the oldest patients, and increases significantly as age at diagnosis goes down. I suppose from the perspective of an 80 year old, curing cancer would in theory increase life expectancies by ~ 3 years, though I wonder how many people die of "old age" but have an undiagnosed cancer of some form contributing.

pessimizer 2y ago
Most people don't have cancer, so the average lifespan reduction of everyone is going to be quite a bit lower than the average lifespan reduction of people diagnosed with cancer.
pcwalton 2y ago
It's because of the Gompertz mortality law [1]--the probability of dying at a certain age is exponential. If you assume that the mortality of each age-related terminal illness itself follows the Gompertz law, then eliminating any one of those illnesses won't affect the overall life expectancy much, because exponential growth is so powerful. Even if we had cures for all age-related diseases except, say, Alzheimer's disease, the fact that Alzheimer's disease mortality also follows the Gompertz law (probably a reasonable assumption) would lead to lifespans not dissimilar from our present ones. Essentially, in order to achieve dramatically longer lifespans, we would need to eliminate, or at least significantly slow, all aging-related causes of death. [1]: https://en.wikipedia.org/wiki/Gompertz%E2%80%93Makeham_law_of_mortality https://en.wikipedia.org/wiki/Gompertz%E2%80%93Makeham_law_o...
The_Colonel 2y ago
Keeping the body alive is a low bar. Lost quality-adjusted life years would be a better measure. Many people survive for many years with cancer, but the quality of life drops significantly.
petercooper 2y ago

adamredwoods 2y ago

Three years would be an amazing amount of precious time with a loved one. I know this.