The statement of qualification in your advertisement for a Registered Dietitian in Ontario should simply read, "Membership with the College of Dietitians of Ontario is required". 

A membership with the College means that a dietitian has fulfilled all the requirements to practice in Ontario, including:
  1. Academic preparation from an accredited Canadian university program in foods & nutrition or equivalent;
  2. Practical training in an accredited practical program in Canada or equivalent;
  3. Language proficiency in English or French;
  4. Record of ethical and competent Practice;
  5. Good character and good conduct;
  6. Current dietetic knowledge and competence;
  7. Eligible to work in Canada; and
  8. Having passed the Canadian Dietetic Registration Examination.
Some employers advertise for RDs who have successfully completed a dietetic internship program accredited by Dietitians of Canada. This internship requirement is a systemic discrimination based on country of origin and against internationally educated professionals who have been assessed by the College to have equivalent practical training. 

Employers who continue to restrict hiring to Canadian trained RDs are vulnerable to a challenge under the Human Rights Code.