I drink diet sodas and work with fat people who do as well. You’ve hit the nail on the head. Diet sodas give the fat people an excuse to eat more of the junk they like. It’s like they think they have a calorie budget and diet sodas give them more leeway to eat junk.
Agreed. But it might be more than just a mental thing. It could be, as the article mentions, that the body is 'tricked' into thinking it needs more sugar.
“The researchers believe that the artificial sweeteners may activate more reward centers in the brain. This in turn affects a person’s appetite, making the diet drinkers eat more food because they don’t think they are getting enough sugar in their bloodstreams.”
http://www.cbsnews.com/news/diet-soda-drinkers-consume-more-calories-study/