The Nutrigenomics, Overweight/Obesity and Weight Management Trial (The NOW Trial)

The focus of this research is to gain a better understanding of how the science of nutrigenomics can improve the long-term health and quality of life of individuals who are overweight/obese as well as patients following an organ transplant. Nutrigenomics is the study of how the foods we eat and beverages we consume interact with our genes, which influence our health. Not all people possess the same genotypes. We all have individual variations within our genome, which explains why there is widespread variation in how people respond (in terms of changes to health) to different nutrition plans. For example, the science of nutrigenomics helps to explain why some people benefit greatly from a moderately high protein diet for weight loss, while others have enhanced weight loss results from following a low-fat nutrition plan.

In this study, participants will either receive general, population-based nutrition advice or nutrition advice based on their genetic profile. Each participant will attend group-based weight loss counseling sessions led by a Registered Dietitian (RD). The RD will provide advice on how the individual should change what they are eating based on either their genetic test results, or based on general nutrition advice (not based on genetics). The research team will then assess how the provision of genetic testing results for weight loss impact attitudes and intentions towards lifestyle change, nutritional habits, physical activity habits, body composition (muscle mass vs. fat mass), weight and BMI.

Additionally, there is a genetic variant that is common in the transplant population, which can be used to predict weight gain post-transplant. However, researchers have not yet identified a dietary strategy that can mitigate this risk in those individuals with the genetic variant. This study seeks to find a dietary strategy that people who have the high risk genetic variant can follow in order to prevent weight gain, and promote weight loss. Overall, this research study will aim to demonstrate if nutrigenomics testing should be used to improve lifestyle habits and health outcomes in two distinct patient populations.

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  • Horne, J.*, Gilliland, J., O’Connor, C., Seabrook, J., Hannaberg, P., & Madill, J. (2019). Study protocol of a pragmatic randomized controlled trial incorporated into the Group Lifestyle Balance™ program: the nutrigenomics, overweight/obesity and weight management trial (the NOW trial). BMC public health19(1), 310. doi: 10.1186/s12889-019-6621-8

For further information about The NOW Trial, contact investigators:

Justine Horne, MScFN, RD
Lead Investigator

Dr. Jason Gilliland
Director, HEAL Lab
Principal Investigator

Dr. Janet Madill, RD