Okay, you're worried about too much data and false positives, but that's a problem you can get around by smoking a pack a day and not going to the doctor. The vast majority of people on the planet have exactly zero hard data on their ailments, and even if they spend their life savings trying to get a clear picture they may never have one.
Could this much potentially frivolous data unlocked for semi-literate worriers and conspiracy theorists lead to whole subreddits full of people freaking out about questionably meaningful physiological aberrations? Definitely. But that's just a variation of "a little knowledge is a dangerous thing," and I believe we crossed that threshold as a society some time ago. So bring on the terabytes and let's see what we can do with them.