Each of us must weigh the relative positive and negative factors associated with drinking diet sodas. The sodium content may be of greater concern to someone with blood pressure issues or who has fluid retention problems. Here are some points to consider when deciding whether to eliminate diet soda from your diet:
1) Are you consuming so much of it that it replaces the water you should be drinking? Be sure to drink an appropriate amount of water each day, and add soda/coffee/tea/juice/whatever on top of that - not instead of it. I live in the desert, and it's way too easy for me to always grab a Diet Coke when I'm thirsty. Unlike some people, I enjoy water as well, so I keep a supply of Dasani (my favorite) at home and in my office. When I find myself reaching for the Diet Coke, I ask myself if it's because I'm thirsty or just in the mood for a pop. If I'm thirsty, I drink water instead. I save the Diet Coke for snack time or for meals that just taste better with pop instead of water.
2) Has the soda become another food-related addiction for you? If so, you may need to consider making it a challenge you'll focus on at some point in your weight-loss journey. It's easy to let go of one food obsession only to grasp another. Successful weight loss requires that we break the cycle of our relationships with food.
3) Be careful about giving up everything you love. Making lifelong changes in how we eat means letting go of some habits we thought we'd never break, but going cold turkey on everything you love is a recipe for disaster.
4) If you hit a plateau and have to examine your eating patterns, it might be time to ask if you're consuming too much soda. If that's the case, you might try cutting way back (or eliminating it altogether) for a week or so and see if that helps get you over the hump.
Personally...I've decided to keep my Diet Coke. Whatever the small amounts of chemicals may be doing is small compared to what the weight will do if I don't get rid of it. But that's just one person's informed decision.