Thanks for the question.
No deductions can be taken from wages paid to an employee, except those by law or government rule. .
Now, that being said if you elected to participate in employer sponsored health insurance and agreed to have your insurance premium deducted then they are allowed to do just that. You employer is allowed to make those deductions if you authorized him to do so. If the premium changes, then your deductions will change. But the employer can't require you to participate in the health insurance.
I hope this helps.