Health insurance premiums are normally excluded from Wages on your W-2 for federal income purposes. They are normally reported with code DD in box 12. If, for some reason, some state did not permit the exclusion of health insurance premiums (although none come to mind at the moment), then the premiums would be added back to box 16. That is assuming that the difference between box 1 and box 16 is the health insurance premiums and not something else.
So, as Anita says, please contact the payroll people at your employer and ask them why box 16 is larger than box 1. That will get you the answer most quickly.