Why?, there are a lot of diet sodas that do not contain any calories.
> Avoid too salty food (preprocessed food will be too salty.)
Why, salt doesn't contain any calories.
Going on a diet is very hard in the first place, giving up these two things doesn't seem to make much sense. It will only make a difficult lifestyle change even more difficult.
The most convincing argument to avoid aspartame has been a behavioral reason. Sweets beget sweets. By enjoying an artificially-sweet diet soda it will be easier to choose a conventional sweet treat if you wander back into the kitchen.
Also, as anyone who has abstained from sweets can attest, after a few days the idea of sweet candies just don't sound appealing.
Everything in too high quantities is bad anyway.
http://www.forbes.com/sites/daviddisalvo/2013/03/24/study-ea... It's not affecting your weight, but your overall health.
Also salty food makes you thirsty, so as toble commented, you will drink more diet coke that will makes you more hungry.
I think a glass of iced tea (even with a little bit of cane sugar to remove bitterness) is better than a diet coke. I can't prove why, every people in good shape I know don't drink diet soda. Just try and see is my best advice !
What is so bad about just drinking water with the occasional tea or coffee if you really need a stimulant?
Just drink water. It's virtually free. Soft drinks allow for a huge profit margin because they have been processed and you have been programmed over years to like them.