I always heard the big problem in soft drinks is that it reduces calcium bioavailability dramatically...
When I was a freshman in high school, I was fat. All my childhood, I ate absolutely everything I wanted - bacon, burgers, cheese, regular sodas, chocolate, ice cream, etc. - while staying very skinny. Then it caught up with me. Not knowing diddly squat about nutrition, I stupidly decided to go on a diet coke diet: I would limit myself to 900 calories a day, and anytime I was hungry beyond that, I would drink diet coke. I did this the entire summer.
I have no idea how I managed to survive that, but since I took this ridiculous course during the time most guys my age had their growth spurts, I wonder if it's partly the reason I'm six inches shorter than my dad is, and why my wrists, etc., are sooooooo slender. Is it possible it affected my bone development? I was drinking liters of soda a day.
Man, ever wish you could go back and redo your life?? Fortunately in college I got on the fitness track, took a nutrition class, and generally improved my life :)