Thanks for the great question. Actually, there is often a generalized, halo effect from using one kind of imagery that overflows into other aspects of a person's life, so this isn't surprising, tasty lasagna notwithstanding.
There are many reasons why your listening to the Self-Confidence imagery could help reduce your interest in eating. For starters, pretty much all the imagery, including the Self-Confidence imagery, is relaxing and de-stressing, so if you're a stress-eater, whose appetite revs up when you're anxious or upset, the calming effects of the imagery are going to make a dent on your compulsive eating.
Second, most of our imagery, including the Self-Confidence imagery, provides some general uplift, increasing serotonin levels (and related neurohormones) in the bloodstream. Heightened levels of these biochemicals reduce appetite.
And third, if your eating is connected to feelings of insecurity and discomfort with yourself, the Self-Confidence imagery would (we hope and expect) remediate some of that, usually in a nice, sneaky, incremental way that you may not even notice at first. Hopefully that's at work as well.
For all those reasons, this imagery could well be helping with your goals for weight loss. The good news is, when you're good and sick of the confidence imagery and move over to the Weight Loss audio, you should get some added bang for your buck, and a really good response to that more targeted imagery. Please let me know - I'll be eager to hear.