I would guess next to nothing. It is made using mannitol, peppermint and menthol – like other sugarfree gums. But you may just ask the manufacturer at customer.relations@gsk.com

Have you tested if you really need the stuff. Within the first weeks of my 5:2 lifestyle I forgot my Niquitin Patch and found out that I no longer needed it (after years of trying to get rid of them). Nice to save that money every week!