If you look at life expectancy difference for teens and young adults, seems like the main difference between the 1800s and today is that instead of dying at you

If you look at life expectancy difference for teens and young adults, seems like the main difference between the 1800s and today is that instead of dying at your late 40s/50s you die in your 70s/80s, which is very intuitive to me at least. This is when regular visits to the doctor become important. I wouldn't be surprised if heart issues alone is the main driver of this trend.