I’m Dr. Nanci Guest, in private practice since 1996 (formerly Power Play: Nutrition, Fitness, Performance) in the health & fitness industry. I am a University of Toronto Researcher, Registered Dietitian, Personal Trainer & NSCA Certified Strength and Conditioning Coach. I completed my PhD in Nutritional Sciences at the University of Toronto, where I researched “Nutrigenomics & Athletic Performance” with a particular interest in caffeine response & genetic variation (more papers coming from this data 2021). I offer this type of Genetic Testing for Personalized Nutrition (Plant-Based reports available) to athletes & the general public.

I also specialize in advanced sports nutrition as an international consultant. I help athletes who follow dietary patterns that include omnivorous, plant-based & vegan. I am currently researching high performance athletes & their unique genetic response to dietary nutrients & supplements based on their genotype (DNA) as well as researching plant-based diets for athletes and the general population, during my post-doc fellowship at UofT.

In addition to research, I run a private practice with a variety of fitness/nutrition services. I serve athletes of all ages & levels as well as healthy individuals in the general population. Check out my *COVID-SAFE* outdoor bootcamp and in-home training in Leaside and now in Collingwood!

Nutrition Consulting

Nutritional consulting, dietary analyses, seminars and grocery store tours offered to individuals, families, team mates, school/sport team groups and more. Dietitian health benefits/coverage applicable to all services.
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Genetic Testing

The Nutrigenomix-Sport genetic test is now available. My goal is to help athletes reach their genetic potential by aligning their diet to their DNA.
Details at
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Dr. Nanci S. Guest is your expert in personal training for all ages and fitness levels, performance conditioning for athletes at all levels, and nutritional consulting all ages/sports in Toronto, Ontario.
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Nutrition • Training • Genetics

Toronto: 416.873.3312  |  Vancouver: 604.818.8348

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