The more you have of something, the more you want. Desire grows with experience and availability, not just with need.
This proverb began as a literal observation: doctors and cooks in Renaissance Italy noted that people who thought they were not hungry often found, once they began eating, that their appetite increased rapidly. The physiological observation — that digestion triggers appetite rather than suppressing it — was documented by Renaissance physicians and quickly became a popular metaphor for the self-reinforcing nature of desire in all its forms. Rabelais cited a French version of the proverb in Gargantua (1534), and the Italian form is recorded in collections of the same period. Over time the proverb detached entirely from its culinary origins and became a general statement about how ambition, greed, curiosity, and desire all grow rather than diminish once indulged. It is used in both approving and cautionary senses: approvingly, when someone discovers a new passion through first experience; cautionarily, when someone's greed or ambition seems to expand dangerously with each satisfaction. In Italian food culture the phrase retains its literal meaning and is used affectionately when someone who claimed not to be hungry ends up eating enthusiastically.
Began as a Renaissance medical observation; cited in Rabelais's Gargantua (1534) in French form; Italian version recorded in the same period.
Discovering a new hobby
Ho letto un solo libro di filosofia e ora ne voglio altri venti. L'appetito vien mangiando.
I read just one philosophy book and now I want twenty more. Appetite comes with eating.
At the dinner table
Diceva che non aveva fame, ma ha preso il bis. L'appetito vien mangiando!
He said he wasn't hungry, but he went back for seconds. Appetite comes with eating!
Career ambition
Ha ottenuto una promozione e ora vuole il posto del direttore. L'appetito vien mangiando.
She got a promotion and now she wants the director's position. Appetite comes with eating.
Shopping
Sono entrata per comprare un paio di scarpe e ne ho prese quattro. L'appetito vien mangiando.
I went in to buy one pair of shoes and bought four. Appetite comes with eating.