Relative contribution of insulin sensitivity and [beta ]-cell function to plasma glucose and insulin concentrations during the oral glucose tolerance test

Effect of Low-Fat vs Low-Carbohydrate Diet on 12-Month Weight Loss in Overweight Adults and the Association With Genotype Pattern or Insulin Secretion

“…Before randomization and at months 6 and 12, each participant completed an oral glucose tolerance test of 75 g. This included measurement of insulin concentration 30 minutes after glucose consumption (ie, INS-30, which is a proxy measure of insulin secretion). 10,21,22 When this study was first designed, insulin sensitivity was to be measured and used as a predictor of differential weight loss success. After the study was initiated, reports were published 12,13,23,24 indicating INS-30 was a successful predictor of weight loss in the context of low-carbohydrate diets or similar diets.…”

Comparison of the relationship of age and beta cell function in three ethnic groups

“…23 With the assessment using hyperglycaemic clamp, we previously demonstrated that insulin sensitivity, but not beta cell function, is the primary determinant of postchallenged plasma glucose concentrations at 120 min. 24 Thus, in glucosetolerant subjects, HbA 1C is primarily determined by postchallenged plasma glucose concentrations, which is mainly affected by insulin sensitivity (%S) but not beta cell function (%B). Therefore, we observed a correlation of HbA 1C with %S, but not with %B in simple regression analyses.…”

Relationship of insulin dynamics to body composition and resting energy expenditure following weight loss

“…Glucose concentrations were measured by enzymatic reference method (LabCorp, 001818), insulin concentrations were measured by chemiluminescent assay (Beckman Coulter, Chaska, MN) and C‐peptide concentrations were measured by competitive radioimmunoassay (Siemens Medical Solutions Diagnostics, Los Angeles, CA). The insulin concentration at 30 min after glucose consumption was used as a measure of insulin response (insulin‐30) . Basal, maximal and total insulin secretion were analyzed by deconvolution analysis of C‐peptide concentrations in response to OGTT using ISEC “I(nsulin‐)SEC(retion)” software, provided courtesy of Dr. Roman Hovorka .…”

“…The insulin concentration 30 min following oral glucose load (insulin‐30) is a novel, reliable proxy measure of insulin secretion . In the Quebec Family Study, baseline insulin‐30 strongly predicted changes in weight over a 6‐year period, such that those with highest baseline insulin secretion gained the most weight .…”

“…The insulin concentration 30 min following oral glucose load (insulin-30) is a novel, reliable proxy measure of insulin secretion (4)(5)(6).…”