Not to that extent, I don't think, or every coffee addict in the world would be skinny as a twig and as parched as the Sahara. Six Dr. Peppers only have the equivalent in caffeine of a cup or so worth of strong coffee, I believe. Not to mention that my own caffeine consumption has been all over the map and back since this summer, and my weight hasn't; and the OP says she's lost weight cutting out soda before.
I'd guess it's more what others have said -- either pure chance in terms of water weight, an unconscious increase in calories elsewhere, or a combination of both.
Height 5'8 1/2"
GW: Originally 150. Maintaining at about 146 since June 2013.
5K 4/21/11: 31:55
|40 Maintenance Weeks