Comparison between a low glycemic load diet and a Canada Food Guide diet in cardiac rehabilitation patients in Ontario.

Abstract

Background: A high dietary glycemic load is associated with an increased risk of noninsulin-dependent diabetes mellitus and coronary artery disease.

Objective: To evaluate the effect of a low glycemic load diet on cardiac rehabilitation patients.

Methods: One hundred twenty patients who were advised to follow a low glycemic load diet were evaluated and compared with 1434 patients who were advised to follow the principles of Canada's Food Guide to Healthy Eating for People Four Years and Over as part of the Ontario Cardiac Rehabilitation Pilot Project.

Results: Patients on the low glycemic load diet lost more weight at six months (2.8 kg loss versus 0.2 kg gain, P < 0.0001), had a greater reduction in abdominal obesity (2.9 cm versus 0.4 cm, P < 0.0001), and had a greater improvement in high density lipoprotein cholesterol (0.14 mmol/L versus 0.02 mmol/L, P < 0.0001), triglycerides (-0.44 mmol/L versus -0.08 mmol/L, P < 0.0001) and glycemic control (fasting glucose -0.94 mmol/L versus 0.91 mmol/L, P = 0.0019). After one year of follow-up, the low glycemic load patients had maintained (weight gain 0.7 kg, triglycerides -0.07 mmol/L, fasting glucose -0.10 mmol/L and glycosylated hemoglobin A1c -0.18%; all not significant) or augmented (waist circumference -1.3 cm, P = 0.038; high density lipoprotein cholesterol 0.08 mmol/L, P < 0.0001) the initial results.

Conclusions: Implementation of a low glycemic load diet was associated with substantial and sustained improvements in abdominal obesity, cholesterol and glycemic control.