Moved here 6 months ago, and have heard mixed reports (very un-Singaporean) about this.

My understanding is that you're not allowed to bring it in (colleagues coming from JB have been stopped), and they can make you throw it away, record your IC/Passport number and tell you not to do it again. Then again, my impression is that Customs are much stricter with chewing gum on land crossings rather than entry by plane (they're more worried about drugs, alcohol and tobacco).

In Singapore, buying chewing gum is legal now, as long as it's for health purposes (so Nicorettes and its brethren are ok, I assume the Wrigley's 'for healthy gums' product passes muster on that basis too). When buying gum (from the pharmacy, normally), I've heard reports of IC/Passport numbers being asked/recorded, and of no questions asked at all. Not sure what's going on there...

Possession of chewing gum will NOT get you caned (caning must be sentenced in conjunction with a jail sentence), but you will be warned/possibly fined (if a repeat offence).