Regular soda or diet soda—which is worse?

The other day, as I wheeled my cart down the soft-drink aisle to pick up some seltzer, my 3-year-old pointed at the soda and said (loudly),“Soda’s baaaaaaad.” First thought: I’ve never directly said that to you… but right on, little man! Still, I didn’t want my preschooler schooling all the people who’d come to pick up pop (as we call it where I grew up). That’s just rude. So I said, “Well, we like seltzer better, right?”

Related: 10 Expert Food Rules to Follow

While I don’t go around telling people soda is “baaaaaad,” I don’t think it’s good: it’s full of sugars or sugar substitutes; some kinds of soda, namely colas, contain phosphoric acid, which, according to some studies, may harm bones. That said, I don’t always avoid soda: now and then, I’ll order one to have with a burger or with popcorn at the movies. I usually order a Diet Coke. Why? For years, I drank tons of diet soda—and that’s what my taste buds grew to like. But when it comes to diet soda versus regular soda, what’s really the better choice?