Some folks last better than others.
My Mother used to be a home help and she used to do a bit of work for an old gent. He had to give up visiting the 'old folk' when he hit 100 (most of he people he visited were 20yr younger than him) and he lived in his own house until he took ill and passed when he was 101. He was an old farmer and still had hands like shovels and a handshake that would crack your knuckles.
I've seen some folk in their 40s that looked in worse health than he did at 100.