Electronic Thesis and Dissertation Repository


Master of Science


Epidemiology and Biostatistics


Dr. Sisira Sarma


Background: The relationship between diet quality and obesity is unknown in Canadian adults.

Objectives: The objective of this study is to examine the association of diet quality with obesity in Canadian adults.

Methods: Data were taken from the 2004 Canadian Community Health Survey. Three indices were constructed using diet recall data: Diet Quality Index (DQI), Healthy Eating Index (HEI) and Glycemic Index (GI). Obesity was measured with body-mass index. Various confounders were also controlled. Latent-class and ordered probit modeling were used to investigate the association between diet quality and obesity.

Results: Latent-class analysis suggested that the association between diet quality and BMI varied across two latent BMI classes, with DQI/HEI having a stronger association with BMI in the high-BMI class. DQI/ HEI were also associated with increased probabilities of overweight/obese. GI was not statistically significant.

Conclusions: DQI and HEI are associated with lowered risk of overweight/obesity, and lowered BMI in the high-BMI class of Canadians.