The government and media have been very successful in putting over the idea that modern medicine is the miracle of the age. Actually, it was things like indoor plumbing, sanitation, and nutrition that have been responsible for longer life spans. Have you ever looked up some historical figure, say from the 18th or 19th century? Look at his wikipedia entry. He probably lived to a ripe old age and never suffered dementia. Thomas Jefferson comes to mind -- died at 83 years of age in 1826. Andrew Jackson only lived to be 78 but he had been shot in the chest in a duel about 40 years earlier. There are many more examples, many of them that lived well into their 90s and often enjoyed reasonably good health right up to the end.