The can has been opened many times before on this forum. No worms. All cigar glues are long-chain carbohydrates—starches. Old fashioned wallpaper paste is edible, and can be used as cigar glue. Commercially, Bermacol is often used in cigar factories. Xanthan gum, gum Arabic, corn starch, etc. can all be used as cigar glue. Some people can taste certain cigar glues, while other cannot.
Since the exterior of the cigar is not glued to anything, applying glue only to the interior surfaces will avoid any shiny appearance. Apply the glue sparingly. A properly wrapped cigar needs only a tiny dab of glue at the head of the binder, and a tiny dab of glue at the head of the wrapper. My preference is for cigar glue that is the consistency of molasses (treacle). Once hydrated, I store it in the fridge.
I know from the many previous discussions of this subject that every cigar rolling forum member has his or her own preference for glue selection and consistency, as well as application method.
Bob