I've been told by a nutritionist that they've seen many of their patients stop drinking either sugarless/diet soda or carbonated non-soda, such as carbonated water made in a home carbonation machine, and lose a notable amount of weight.
I've heard of, but admittedly been unable to find, research saying that people who stop drinking sugarless/diet sodas lose some weight. But I can neither find nor conceive of any reason that the same would be true for carbonated water.
Is there any research to back up this observation? Or, if there is no research to be found, is there any biochemical/chemical reason that this observation makes sense?