Improved Plasma Glucose Control, Whole-Body Glucose Utilization, and Lipid Profile on a Low-Glycemic Index Diet in Type 2 Diabetic Men

Abstract

OBJECTIVE -To determine whether a chronic low-glycemic index (LGI) diet, compared with a high-glycemic index (HGI) diet, has beneficial effects on plasma glucose control, lipid metabolism, total fat mass, and insulin resistance in type 2 diabetic patients.RESEARCH DESIGN AND METHODS -Twelve type 2 diabetic men were randomly allocated to two periods of 4 weeks of an LGI or HGI carbohydrate diet separated by a 4-week washout interval, in a crossover design. RESULTS -TheLGI diet induced lower postprandial plasma glucose and insulin profiles and areas under the curve than after the HGI diet. At the end of the two dietary periods, the 7-day dietary records demonstrated equal daily total energy and macronutrient intake. Body weight and total fat mass were comparable. Four-week LGI versus HGI diet induced improvement of fasting plasma glucose (P Ͻ 0.01, ⌬ changes during LGI vs. HGI), HbA 1c (P Ͻ 0.01), and whole-body glucose utilization measured by the euglycemic-hyperinsulinemic clamp (P Ͻ 0.05).LGI diet induced a decrease in fasting plasma total and LDL cholesterol (⌬ changes LGI vs. HGI, P Ͻ 0.01), free fatty acids (P Ͻ 0.01), apolipoprotein B, and plasminogen activator inhibitor 1 activity. CONCLUSIONS -Only 4 weeks of anLGI diet was able to improve glycemic control, glucose utilization, some lipid profiles, and the capacity for fibrinolysis in type 2 diabetes. Even if changes in glycemic control were modest during the 4-week period, the use of an LGI diet in a longer-term manner might play an important role in the treatment and prevention of diabetes and related disorders. Diabetes Care 27:1866 -1872, 2004D iabetes is a chronic evolving disease associated with a variety of microand macrovascular complications. Increasing postprandial plasma glucose and insulin excursions are assumed (1,2) to increase severity of diabetes and to be independent predictors of risk for atherosclerotic diseases. As such, interventions to reduce postprandial plasma glucose and insulin peaks are one of the essential therapeutic objectives for diabetic patients and could reduce the risk of developing cardiovascular complications.Because dietary carbohydrate is one of the main factors in controlling postprandial hyperglycemia, it is reasonable to question whether the type of dietary carbohydrate can modify the evolution and complications of this disease in a clinically significant long-term fashion.There is growing recognition that the postprandial glycemic (3,4) and insulinemic (5) responses to different foods may vary despite equal amounts of total absorbable carbohydrates. This concept favors the use of low-glycemic index (LGI) carbohydrates. Although focusing on the total amount of carbohydrate intake is important for diabetic patients (6,7), using LGI carbohydrates could lead to additional benefits without increasing the fat content of the diet and consequently increasing plasma free fatty acids (FFAs), with all their deleterious consequences (8).Whether the glycemic index (GI) of foods has relevance to human health has been a topic o...

Dietary fiber intake, dietary glycemic index and load, and body mass index: a cross-sectional study of 3931 Japanese women aged 18–20 years

“…Our dietary GI and GL values (65 and 147), consistent with those in a previous Japanese study (64 and 150) (Amano et al, 2004), were higher when compared with those in Western countries (49-58 and 81-145) (Salmeron et al, 1997a, b;Toeller et al, 2001;Heilbronn et al, 2002;JimenezCruz et al, 2003;Rizkalla et al, 2004;Scholl et al, 2004;Schulze et al, 2004Schulze et al, , 2005Ma et al, 2005;Sahyoun et al, 2005). This may primarily result from the differences in the major food contributors, whereas dietary GI and GL in Western populations were determined by a variety of foods (potatoes (7-8%), breakfast cereals (4-7%), bread (5%) and rice (5%)) (Liu et al, 2000(Liu et al, , 2002Jonas et al, 2003), the contribution of white rice (GI ¼ 77) was dominant in the present study (46%).…”

“…Several ad libitum trials conducted on nondiabetic subjects have suggested a beneficial effect of low-GI diet on fat mass (Bouche et al, 2002) and body weight (Bouche et al, 2002;Sloth et al, 2004), when compared with high-GI diet, although other trials conducted on subjects with type II diabetes have found no differences in body weight change between high-and low-GI diets (Heilbronn et al, 2002;Jimenez-Cruz et al, 2003;Rizkalla et al, 2004). Additionally, although there has been no association between dietary GI and GL and BMI in some studies (Amano et al, 2004;Liese et al, 2005), other observational studies have shown a positive association between dietary GI, but not dietary GL and BMI Murakami et al, 2006b).…”

PDA-assisted low glycemic index dietary intervention for type II diabetes: a pilot study

“…Results were consistent among type II diabetic patients (Jenkins et al, 1988(Jenkins et al, , 2002Gulliford et al, 1989;Wolever et al, 1992;Jarvi et al, 1999;Tsihlias et al, 2000;Heilbronn et al, 2002;Kabir et al, 2002;Brynes et al, 2003;Gilbertson et al, 2003), where low-GI diet improved plasma glucose control and had the added benefit of significantly decreasing cholesterol. Supporting the results from our study, a limited number of clinical trials have demonstrated that low-GI dietary educational interventions delivered by a clinical nutritionist can lead to improved metabolic control in patients with diabetes (Frost et al, 1994;Gilbertson et al, 2001Gilbertson et al, , 2003Rizkalla et al, 2004). These reports are consistent with our findings.…”

The effect of a 12-week low glycaemic index diet on heart disease risk factors and 24 h glycaemic response in healthy middle-aged volunteers at risk of heart disease: a pilot study

“…This might suggest an improvement in hepatic insulin sensitivity resulting in a decrease in hepatic glucose output following meals (Thorburn et al, 1993). Whole body glucose utilization has been shown to improve on a low GI diet as assessed by euglycaemic-hyperinsulinaemic clamp (Rizkalla et al, 2004). This is clinically relevant as raised postprandial glycaemia would increase cardiovascular risk even in the normal glucose tolerance range, although this may be confounded by other heart disease risk factors (Coutinho et al, 1999;The DECODE Study Group, 2001).…”

“…Nevertheless only the low GI group had an improvement in blood glucose levels supporting Wolever's observation (Wolever, 2003) that the metabolic advantage of a slowly absorbed diet (low GI diet) is greater than its glycaemic impact. Reducing the glycaemic load via reduction in carbohydrate intake increases postprandial free fatty acids (FFAs) possibly via reduced insulin secretion and sensitivity (Wolever and Mehling, 2003) whereas a low GI diet suppresses FFAs (Rizkalla et al, 2004). A high plasma FFA concentration is associated with dyslipidaemia and an increased risk of cardiovascular disease (Carlsson et al, 2000).…”