Legal Question in Employment Law in California

All employers are obligated to provide lunch and breaks for all employees, and ensure they are taken. If not, there are financial penalties, interest and attorney fees recoverable for each break or lunch not allowed. Also, in your case, there may be an issue of 'failure to accommodate' a disability under the ADA rules, which would be the basis of a civil lawsuit. If serious about pursuing this, feel free to contact me.

Employers are required to engage in an interactive discussion with employees who suffer from disabilities, such as diabetes, in an attempt to reasonably accommodate them to allow the employee to perform their job. If your manager knows you are diabetic, he or she certainly should be aware you need your meal and rest breaks and work with you, without fear of reprisal. Assuming you are also a non-exempt employee, they may be violating your rights twice.

You should consult with experienced employment law counsel near you to assess you legal options.