Moderation is key right? Nope, not with diet soda. You might think you're saving yourself some calories and eliminating some sugar by drinking diet soda, but the reality is, the drinking of diet soda actually PREVENTS you from losing weight.
I used to be addicted to Diet Mountain Dew. I would have a 12 ounce can with lunch, another 12 ounce can after work, I would even use it to mix with bourbon for a cocktail. During my heavier weight days, I would go through a 2 liter bottle a day of the stuff.
As with any diet, there are plateaus. When I started this Carb-Check Diet, eliminating breads, pastas, rice and other high carb foods from the menu, I lost weight rather easily at first, but then I plateaued. I was eating right and exercising, but dang it, wasn't dropping the weight like I was early on. Then it hit me, I was still drinking that Diet Mountain Dew. Guess what happened when I quit drinking the stuff? Yep, you guessed right, the weight started coming off again.
If you're going to drink a soda (don't do it), you're better off drinking the real deal. Your body can digest real sugar more efficiently, it doesn't know what the hell to do with the artificial stuff. A study from Purdue University's Ingestive Behavior Research Center showed that lab rats fed artificial sweetener actually ate more and gained weight than rats fed regular sugar. The conclusion: Artificial sugar tricked the rats' brains into thinking they would be consuming more calories so their bodies got ready to process those calories. When the calories were discovered as "empty", the rats' metabolism got all screwed up and so did the regulation of appetite. The rats ate more as a result.
So ditch the diet soda, all it does is confuse the body. Eliminating the diet soda from my daily routine has helped me drop more pounds, it will help you too.