I don't agree. Even at 70 and 80, you know day to day if you are healthy. You know whether you are overweight. You know if you have chronic disease. You know if your mind and body are right.
Yes, the hammer could fall at any moment - IF you are an overweight, bacon and sausage eating, high cholesterol, high blood pressure, diabetic mess. That could happen if you are 40 or 50. It is about diet and lifestyle. You don't have to constantly worry about dropping dead if you live right.
Diet and lifestyle do help, but it is more about genetics than anything. My Great-Grandmother lived to 104 and loved eating a good ‘ole fashioned Southern Breakfast of sausage, eggs, bacon, biscuits and gravy. OF course she was never overweight and was a beautiful woman in her prime. Her sister, who lived the same lifestyle, died at 102. Unfortunately, my grandma (her daughter) died at 92 - at the funeral many talked of how her heart problems cut her life short. :)