It's a real thing... well, in a way. Not a literal spare stomach, but there's a thing called sensory-specific satiety which causes you to feel full quicker if you're just tasting the same sort of thing. So if you switch from eating savoury foods to sweet desserts, you suddenly get back your appetite, because you weren't actually as physically full as your body was lying to you about.
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Tea...?Sounds good to me.Why don't we have a little tea and then go back?It was tasty, wasn't it.Whew, I've had my fill.