Not entirely, of course. There are obviously things we can all do to be more healthy and active. We all know the most common ones - don't smoke, moderate alcohol intake, eat healthily etc.
Recently, a number of people I know have fell victim to long-term and serious health conditions. They're all people you'd categorise as normal healthwise i.e. not heavy drinkers, a healthy weight etc.
I'm also thinking of some higher profile people who have died recently (such as Rachel Bland), who for all extents and purposes were normal healthy people, who happened to fall victim to terminal illness.
It makes me very sad. But it also makes me appreciate life on a day-to-day basis.