Mineral Water (not man-made carbonated water, but mineral water that comes out of healthy springs)
Add flavored liquid stevia to taste. Stevia comes in many flavors including root beer, cherry, orange, lemon, lime, and grape, and much more.
Good stevia brands are NOW and Stevita.
Mineral water is loaded with good minerals. The stevia is a natural herb. There is NO sugar or aspartame in it!
Gerolsteiner is a good brand of mineral water.