It could postpone, but I doubt it can suppress real hunger.
One of the advantages is that it usually takes about 20 minutes for the message to get across that you're not really hungry any more, so chewing a gum or having a sugarless candy could help you whet your appetite and you might eat less.
I wouldn't make a habit of chewing gum instead of eating. It could create all sorts of problems which are more difficult to resolve.
