Dietary Glycemic Index and Glycemic Load, Carbohydrate and Fiber Intake, and Measures of Insulin Sensitivity, Secretion, and Adiposity in the Insulin Resistance Atherosclerosis Study

Abstract

OBJECTIVE -We studied the association of digestible carbohydrates, fiber intake, glycemic index, and glycemic load with insulin sensitivity (S I ), fasting insulin, acute insulin response (AIR), disposition index, BMI, and waist circumference.RESEARCH DESIGN AND METHODS -Data on 979 adults with normal (67%) and impaired (33%) glucose tolerance from the Insulin Resistance Atherosclerosis Study (1992)(1993)(1994) were analyzed. Usual dietary intake was assessed via a 114-item interviewer-administered food frequency questionnaire from which nutrient intakes were estimated. Published glycemic index values were assigned to food items and average dietary glycemic index and glycemic load calculated per subject. S I and AIR were determined by frequently sampled intravenous glucose tolerance test. Disposition index was calculated by multiplying S I with AIR. Multiple linear regression modeling was employed.RESULTS -No association was observed between glycemic index and S I , fasting insulin, AIR, disposition index, BMI, or waist circumference after adjustment for demographic characteristics or family history of diabetes, energy expenditure, and smoking. Associations observed for digestible carbohydrates and glycemic load, respectively, with S I , insulin secretion, and adiposity (adjusted for demographics and main confounders) were entirely explained by energy intake. In contrast, fiber was associated positively with S I and disposition index and inversely with fasting insulin, BMI, and waist circumference but not with AIR.CONCLUSION -Carbohydrates as reflected in glycemic index and glycemic load may not be related to measures of insulin sensitivity, insulin secretion, and adiposity. Fiber intake may not only have beneficial effects on insulin sensitivity and adiposity, but also on pancreatic functionality.

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

“…Fiber, glycemic index and load, and obesity K Murakami et al in previous cross-sectional studies (Appleby et al, 1998;Sasaki et al, 2003;Spencer et al, 2003;Howarth et al, 2005;Liese et al, 2005), although one study did not show an inverse association (Stookey, 2001). Higher total dietary fiber intake has also been associated with lower body weight gain (Ludwig et al, 1999) and lower increase in body weight and BMI (Liu et al, 2003) in several prospective studies.…”

“…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).…”

“…Independent positive association between dietary GI and/ or GL and a measure of obesity has been reported in several (Toeller et al, 2001;Ma et al, 2005;Sahyoun et al, 2005;Murakami et al, 2006b), although not all (Amano et al, 2004;Liese et al, 2005), observational studies. In contrast, intake of dietary fiber (unavailable carbohydrate) has been shown to be independently negatively associated with a measure of obesity in several (Appleby et al, 1998;Ludwig et al, 1999;Liu et al, 2003;Sasaki et al, 2003;Spencer et al, 2003;Howarth et al, 2005;Liese et al, 2005), but not all (Stookey, 2001), observational studies.…”

“…In contrast, intake of dietary fiber (unavailable carbohydrate) has been shown to be independently negatively associated with a measure of obesity in several (Appleby et al, 1998;Ludwig et al, 1999;Liu et al, 2003;Sasaki et al, 2003;Spencer et al, 2003;Howarth et al, 2005;Liese et al, 2005), but not all (Stookey, 2001), observational studies. Although high dietary fiber intake is often correlated with low dietary GI and/or GL (Howarth et al, 2001;Bouche et al, 2002;Scholl et al, 2004;Schulze et al, 2004;Sloth et al, 2004;Schulz et al, 2005), few observational studies have examined these dietary factors simultaneously in relation to a measure of obesity, especially in non-Western populations (Toeller et al, 2001;Amano et al, 2004;Sahyoun et al, 2005).…”

Methodology for adding glycemic index and glycemic load values to 24-hour dietary recall database

“…Although many researchers have applied GI estimation values to dietary assessment instruments [14][15][16][17], the methodology used to obtain these values has only recently been documented in detail in a few studies using the food frequency questionnaire (FFQ) [17][18][19]. However, although similar, description of methodology in assigning GI values in 24-hour dietary recalls (24HRs) is currently lacking.…”