Long ago I made a personal rule: don't drink your calories. I bend that rule for protein shakes, but those calories are figured into my day and all accounted for. I switched to drinking diet sodas at that point, and now I can't stand regular sodas. Ugh! It's like drinking a can of syrup.
To me it's an obvious association: you drink your calories and don't figure those in to your day, you gain weight. Um, duh. Do we really need to have this pointed out? (Not attacking the OP, understand, just silliness from the world in general.)
That being said, yeah, I drink diet soda. And I'm absolutely unashamed/unabashed about it. Yeah, I've heard the arguments that it harms your teeth. I've heard that the phosphates are [potentially] bad for your bones. I've heard the claims that Aspartame causes cancer. It's my choice to drink diet soda. I don't drink coffee, I drink lemonade maybe once a week, I rarely drink alcohol...I'm allowed my soda.
That being said, I also lift weights (and have for years) to keep my bones strong, I make sure I get enough calcium in my diet, and I eat (on average) about 7 servings of fruits/veggies a day. I don't like chocolate, my body HATES sugar, the only fried foods I allow myself are tortilla chips once a week, and my once-a-week 'treat' is a French baguette with butter from Panera (split with a friend over gossip). There's gotta be a balance somewhere. My soda is okay.
(But then, if I were drinking the full sugar stuff, it'd be a totally different story! Does anyone ever wish that their diets were that simple
--"oh, hey, if I cut out the soda I'd lose 50 pounds by the end of the year, so that one small change will radically change my life!!" If only I had any of those changes left to make!

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