I found Peter Attia's The Drive episode 311 "Longevity 101:..", enlightening when it comes to longevity. I fear I won't be able to properly explain the key points from memory, but I recommend the listen.
I did always wonder how much of getting to a very old age is just luck.
Like you have two 85 year olds. Number 1 is healthy and has a .01% chance of having a stroke, number 2 is unhealthy and has a .05% chance, but 1 still has a stroke first just due to bad luck.
Maybe number 2 has such a good run of luck that they make it to 100 in spite of smoking and eating cake daily. In that world people over 100 would be more statistical anomaly, for whatever reason the combination of events that trigger a deadly event just never come together for them.
Of some fame because he ordered the first and successful GSG 9 (which was founded because of the failed Munich Olympics rescue operation) assault, despite many not agreeing with him at the time:
In October 1977, he ordered an anti-terrorist unit of Bundesgrenzschutz policemen to end the Palestinian terrorist hijacking of a Lufthansa aircraft named Landshut, staged to secure the release of imprisoned RAF leaders, after it landed in Mogadishu, Somalia. Three of the four kidnappers were killed during the assault on the plane, but all 86 passengers were rescued unharmed
He was an avid drinker and smoker.
On 25 January 2008, German police launched an inquiry after an anti-smoking initiative charged that Schmidt was defying the recently introduced smoking ban. The initiative claimed that Schmidt had been flagrantly ignoring anti-smoking laws. On 6 April 2010, with a lifespan of 33,342 days, he surpassed Konrad Adenauer in terms of longevity, and at the time of his death was the oldest former chancellor in German history.
Seems their findings are that, to grossly oversimplify, some people just have a higher chance of getting sick than others, and that remains consistent from youth to old age. And given how many chances there are to get sick, making it through 'the filter' to get to 100 is only realistically going to happen to those who are both lucky and have that low base rate of disease going for them.
I can't remember where I read it but a large portion of people who are over 100 might be the result of poor record keeping in the past, especially with registration of births at home.
We know this partly also because when countries introduced mandatory birth registration, there was a sudden drop in people who lived beyond 100 years old. Here's a paper from earlier this year on this:
I believe our immune systems and maintenance processes co-evolved with caloric scarcity plus the cellular stress of borderline starvation to keep onco processes in check.
It's curious that cancer and neurodegenerative diseases tend to be mutually exclusive. I wonder if there is genetic &| epigenetic basis for it.
Anecdotally, it's common for elderly people to be doing relatively well and then decline quickly, so this result seems pretty intuitive. I would be curious if this also holds for diseases that aren't as linked to aging.
https://peterattiamd.com/longevity101/