Dr. John Gannage, MD, CCFP, FMAPS

Hi, I’m Dr. John Gannage, founder of Markham Integrative Medicine. My medical background is within the scope of Family Practice, a specialty that ideally emphasizes continuity of care, comprehensive care, health promotion and prevention. Recognizing some limitations in my conventional training, particularly in regard to supporting the “chronically unwell” and today’s chronic disease epidemics, I began the scientific process of searching and observing outside of standard medical training. I support strongly the concept of Integrative Medicine, which incorporates aspects of Complementary Medicine adjunctively with Conventional Medicine. I offer, therefore, a holistic approach with specific emphasis on lifestyle counselling, nutrition and nutritional therapy, functional medicine, and mind-body medicine, areas in which I have special training.

Dr. John Gannage holds an active medical license in good standing with the College of Physicians and Surgeons of Ontario (CPSO) and the College of Physicians and Surgeons of British Columbia (CPSBC). He is considered an expert in the field of Complementary and Alternative Medicine (CAM), and is regularly requested to offer his opinion regarding the current standard of care and best practices within his professional domain. 

Dr. Gannage founded and is currently the Medical Director of Markham Integrative Medicine, where he has been emphasizing prevention and treatment of chronic disease through nutrition, detoxification, immune system modulation and reduction of oxidative stress since 1998. Dr. Gannage works with patients from the Greater Toronto Area and beyond, both virtually and in person at Markham Integrative Medicine.

Dr. Gannage has a special focus in assisting children and families affected by developmental issues, including autism, using biomedical therapy. Dr. Gannage has been a member of the Medical Academy of Pediatric Special Needs (MAPS) for several years, and has been awarded MAPS Fellowship in recognition of his extensive training and knowledge in this field. 

Still, the majority of Dr. Gannage’s practice is for chronic illness and conditions among adults, for which he has both learned and developed specific protocols from a Functional Medicine perspective.

In particular, Dr. Gannage has become known for his special interest in Mast Cell Activation Syndrome (MCAS), mast cell instability, histamine intolerance, and the role of each in chronic disease. Dr. Gannage consults virtually with patients from around the world with these conditions, and has developed comprehensive educational programs on the management of mast cell instability and histamine intolerance for both patients and practitioners. 

Dr. Gannage graduated from the University of Toronto medical school in 1990 and completed his residency in Family Medicine at the University of Ottawa. At the University of Toronto, he was recognized with the Medical Society Award for Outstanding Contribution to the Faculty of Medicine. He earned Honours in 3 years at the University of Toronto in the Faculty of Medicine and was President of the Men’s Medical Athletic Association, while also serving on Student Council. 

Dr. Gannage served as Medical Director of Meadowbrook Sport Medicine and Rehabilitation Clinic in Markham, while also operating his Family Practice. His work in Sports Medicine was valuable in galvanizing Dr. Gannage’s interest in holistic and collaborative approaches to health. In 2000, Dr. Gannage was voted Markham’s Best General Practitioner. 

He has studied extensively in the fields of Clinical Nutrition and Functional Medicine, and obtained two diplomas in Homeopathy. Dr. Gannage has membership in the Medical Academy of Pediatric Special Needs (MAPS), the American College for Advancement in Medicine (ACAM), the Canadian Society of Orthomolecular Medicine (CSOM), the Ontario Medical Association (OMA), and its Section on Complementary and Integrative Medicine, and the Canadian Association of Physicians for the Environment (CAPE). 

Dr. Gannage was a principal investigator for TACT (the Trial to Assess Chelation Therapy), enrolling Canada’s first participant. 

Dr. Gannage was appointed to the Medical Advisory for Mindful, a charitable organization and network that provided information on the importance of diet, nutrition, and lifestyle in optimizing children’s mental health. 

In 2014, “Integrative Medicine for Children’s Mental Health” was launched. This program was researched, written, and presented by Dr. Gannage at three universities across Canada.

The professional seminar, co-sponsored by Mindful and CSOM, was recognized for accreditation by the College of Family Physicians of Canada (CFPC). Dr. Gannage continued the professional seminars in 2015 and 2016, in Toronto, Vancouver, Calgary, and Hamilton.

The program’s objective is to provide an evidence-based approach to ASD, ADHD, and other mental health conditions in children to health professionals, including medical doctors, with clinical management guidelines and research outlined. 

Dr. Gannage emphasizes nutrition and environmental factors, and explains the relationship of the gut-microbiome-brain axis, oxidative stress, immune dysregulation, and environmental toxicants to mental health disorders. 

In 2019, the program was modernized and re-launched under the title “Nutritional and Environmental Influences on Neurodevelopment”, after extensive research and content upgrades, and presented to professional audiences in Vancouver and Toronto on the heels of re-accreditation by the CFPC. 

In 2021, Dr. Gannage developed, and presented “Mast Cell Instability: Why It Matters” at the 50th Annual International Orthomolecular Medicine Today Conference to significant praise. This presentation, rooted in the latest research and further informed by Dr. Gannage’s extensive clinical experience, explored the complexity of mast cell activation and how understanding the role of mast cells can lead to better management of chronic, inflammatory conditions. 

Dr. Gannage has also developed a patient-focused online course, Outsmart Histamine, aimed at educating and empowering individuals when it comes to histamine intolerance. While not a replacement for medical advice, this self-paced course provides clear, evidence-based information and resources related to diet, supplementation, testing, lifestyle, and other factors related to histamine metabolism and mast cell activation. 

Dr. Gannage regularly educates the community and other practitioners through public presentations, has appeared on radio, lectured at ACAM’s biannual medical conference, and written numerous articles for publication. 

Dr. Gannage has also presented seminars for the Orthomolecular Health Public Education Series, and authored articles published in the Journal of Orthomolecular Medicine.