Diets high and low in glycemic index versus high monounsaturated fat diets: effects on glucose and lipid metabolism in NIDDM

Abstract

Objective: To examine the relative effects of high and low glycemic index (GI) carbohydrates, and monounsaturated fats on blood glucose and lipid metabolism in NIDDM subjects. Subjects: Fourteen male and seven female variably controlled NIDDM subjects recruited by advertisement. Setting: Free living outpatients. Research design: A repeated measures, within-subject design was used such that each subject consumed three diets: (a) a high-GI diet (53% CHO7 21% fat, 63 GI units (glucose 100)); (b) a low-GI diet (51% CHO 7 23% fat, 43 GI units); and (c) a high-mono high-GI diet (42% CHO735% fat, 59 GI units) in random order and cross-over fashion for four weeks. Approximately 45% energy was provided as key foods which differed in published GI values and speci®cally excluded legumes. Dietary ®bre intake was b 30 gad on each diet. At the end of each dietary intervention, we measured fasting plasma lipids, glucose, insulin, total glycated plasma protein, fructosamine, LDL and HDL particle size as well as 24 h urinary excretion of glucose and C-peptide. Results: HDL-cholesterol was higher on the low-GI and high-mono high-GI diets compared to the high-GI diet (P`0.05 for overall diet effect). There were no other signi®cant differences in metabolic control between diets, even when adjusted for BMI, glucose control or gender. Body weight and saturated fat intake remained stable between dietary interventions. Conclusion: High-mono high-GI and high-CHO, low-GI diets are superior to high-CHO, high-GI diets with respect to HDL metabolism but no effect was noted on glucose metabolism in variably controlled NIDDM subjects. Sponsorship: This study was funded by CSIRO Human Nutrition.

Depression of the glycemic index by high levels of β-glucan fiber in two functional foods tested in type 2 diabetes

“…Since recent studies have indicated that the glycemic index of foods is positively associated with the risk of developing type 2 diabetes (Salmeron et al, 1997a,b) and that low GI diets may reduce glycemia and cardiovascular risk factors in diabetes (Järvi et al, 1999;Fontvieille et al, 1999;Luscombe et al, 1999), development of palatable, low GI or functional foods has become increasingly important. This study shows that each gram of bglucan can be expected to lower the GI of a food by four GI units and that this effect is not attenuated by processing, including the use of fructose to enhance palatability.…”

Glycemic index in chronic disease: a review

“…However, not all carbohydrate-rich diets may produce the same effects on HDL levels, as low-GI diets may confer a more favorable lipid profile compared with high-GI diets. Lowering the dietary GI by at least 12 points reduced triglycerides by approximately 9% in 10 out of 11 studies (Brand Miller, 1994) and recent data showed that a high carbohydrate diet made of low-GI foods significantly increased HDL levels by 5.4% compared to an isocaloric high carbohydrate=high GI diet (Luscombe et al, 1999). In addition, cross-sectional data (Frost et al, 1999;Ford & Liu, 2001) showed that dietary GI was inversely related to HDL cholesterol levels, which in turn were inversely related to triglycerides, and that GI was a stronger predictor of serum HDL levels than dietary fat (Frost et al, 1999).…”

Correlation between dietary glycemic index and cardiovascular disease risk factors among Japanese women

“…On the other hand, Jenkins proposed the glycemic index (GI) as a physiologic basis for qualitative classification of carbohydrate-containing foods, where low GI foods produce less glycemia than high GI foods (Jenkins et al, 1981). Since then, many metabolic studies showed that a low GI diet improves overall blood glucose and lipid profiles in normal subjects (Jenkins et al, 1987a), and patients with hyperlipidemia (Jenkins et al, 1985(Jenkins et al, ,1987b or diabetes (Jenkins et al, 1988;Brand et al, 1991;Wolever et al, 1992a, b;Jarvi et al, 1999;Luscombe et al, 1999). The GI values of 565 foods were compiled to form the international GI table in 1995.…”