Control/Tracking Number: 08-A-1754-IFT
Activity: Technical Research Papers
Low glycemic load diet, glycemic control and serum lipids: a case report
Author Block: Cheryl A. Krone, Applied Research Institute, Palmerston North, New Zealand
Abstract: Diets with differing glycemic index (GI)/glycemic load (GL) have shown the ability to influence blood lipids and cardiovascular disease risk. Most controlled GI/GL dietary studies have focused on weight loss in obese adults who often have concurrent Type 2 diabetes. Moreover, seldom is glycated hemoglobin A1C (e.g., GHb, longterm average blood glucose) measured as an endpoint. We examined the effect of dietary glycemic load (GL) on indicators of glycemic control and risk factors for cardiovascular disease (e.g. serum lipids) over a 1 year period in a non-obese, non-diabetic, free-living subject. The subject was a post-menopausal female age 58 with a family history of cardiovascular disease and Type 2 diabetes. Dietary counselling was provided with a goal of reducing GL of the diet to less than 80. Food diaries and dietary questionnaires were used to evaluate typical
daily GL. Fasting blood glucose, GHb and serum lipids were determined by commercial clinical laboratory at 3 month intervals for 1 year. A 75g oral glucose tolerance test was performed at beginning and end of the study.
Daily GL was decreased from over 120 initially to 80 in about 6 months and even lower in the following 3 months. Fasting blood sugar (mean 4.0 ± 0.055 mmol/L; n=5) and glucose tolerance did not change. GHb ranged from 5.1% to 5.6% and did not correlate with dietary GL. Total cholesterol and serum lipids varied from borderline elevated to high. The highest total cholesterol (7.0 mmol/L) and LDL (4.5 mmol/L) occurred when consuming the lowest (<70) GL diet. In non-diabetic,
non-obese individuals, lowering of dietary GL may not significantly decrease average blood glucose. Dietary factors other than amount and type of carbohydrate appear to have a relatively greater influence
on measures of cardiovascular disease risk such as total cholesterol and LDL.