Not sure if I believe it or not, but ....
I'm sure a lot of CEO's of health monitoring equipment companies had heart attacks this morning! If the iWatch is capable of monitoring Blood Glucose non-invasively, They will sell like crazy! Even at $1000. with current monitors, you are paying between .5 an 1 dollars per test. if you have to test 6 times a day, the device would pay for itself with in a year. Now imagine it is connected by bluetooth to you insulin pump! continuous automatic adjustment. Also being able to measure at multiple points during the day without worrying about cost. You would be able to get real-time personal information about how specific foods and activities affect your blood sugar. For the people who really want to develop a healthy lifestyle this would be invaluable.
I'm not sure I beleive the the iWatch will have this capability but I hope so and I will be buy one for my wife and myself on day one if it does regardless of the cost. I'll also say this. if you even think this is true, I would load up on AAPL because it will go through the roof
Just my humble opinion