Currently OHIP does not cover Naturopathic, Nutrition, Chiropractic or Osteopathic visits.
Many private insurance companies may assist the cost of Naturopathic, Nutrition, Chiropractic and Osteopathic care.
So please check your individual plan as each plan is different. Most plans do not cover nutritional supplements and or lab testing.
Naturopathic Care is recognized in Ontario as a medical practitioner for the purpose of claiming medical expenses for tax purposes. The Naturopathic products though are not eligible for deduction, only services.
Please see the link to CRA website for more details.