We know what is in water. A couple of parts hydrogen, and a part of oxygen. What's inside a can of decaffeinated diet Coke?

Every liquid we drink has ingredients we pretty much understand. Beer has plenty of water, other ingredients, and alcohol. Cola has plenty of water and sugar, carbonated. Milk has plenty of water and whatever else that makes it milk.

What about decaffeinated diet Coke? What's in there?

Water, of course. It seems to be in everything we drink except a glass of microwaved Peter Pan peanut butter, which is actually better than it sounds, though you have to drink it quickly, and not too much at a time.

Diet drinks without sugar or caffeine? There's taste, though it's not as good as the real thing. Diet Coke breaks my dietary rule of not eating what I cannot pronounce.

Still, the ingredients are interesting. Carbonated water, caramel color, aspartame (which replaces the sugar), phosphoric acid (used to reduce rust on metal, so I wonder what it does to teeth), and other things that don't make it through my spellchecker.

It isn't common for us even to consider what's in our drinks, let alone ask for a list of ingredients. It's just not what we do. Maybe we should. I can't find anything in a can of Pepsi-cola (my favorite) that's good for me except the taste. Take out the sugar and the caffeine and what do you have left?

A carbonated can of some kind of chemical soup, chilled.