Comparison of the Metabolic Response to a Glucose Tolerance Test and a Standardized Test Meal and the Response to Serial Test Meals in Normal Healthy Subjects

Abstract

The plasma glucose and insulin response to a standardized meal test breakfast was compared with the time-honored glucose tolerance test in the same normal healthy subjects. The amplitude of glycemic excursion and between-subject variation was less with the more physiologic standardized test meal than with that seen with the glucose tolerance test. The glucose tolerance test's prime function is to amplify any glucose intolerance, thus aiding diagnosis, whereas a standardized meal gives a more clinically relevant metabolic status. The administration of serial test meals during the same day in a smaller group of normal subjects indicated, as seen previously with repeated glucose tolerance tests, a diminishing carbohydrate tolerance during the day.

Effects of size, time of day and sequence of meal ingestion on carbohydrate tolerance in normal subjects

“…A similar effect has not been uniformly reported for carbohydrate tolerance to mixed meals [15][16][17][18]. Reduced carbohydrate tolerance to mixed meals was observed by Owens et al [18], and, although not commented on by Genuth [16], is evident from analysis of his data; Ahmed et al observed the phenomenon in females and not males [17]. In contrast, Malherbe et al reported that there was no evidence for a diurnal variation in carbohydrate tolerance to mixed meals [15].…”

“…It has long been recognized that there is a diurnal variation in response to oral glucose loads, characterized by reduced tolerance later in the day [9][10][11][12][13][14]. A similar effect has not been uniformly reported for carbohydrate tolerance to mixed meals [15][16][17][18]. Reduced carbohydrate tolerance to mixed meals was observed by Owens et al [18], and, although not commented on by Genuth [16], is evident from analysis of his data; Ahmed et al observed the phenomenon in females and not males [17].…”

“…No correlation between meals of different sizes and post-prandial plasma glucose responses was observed in the only study to examine this relationship [8]. Although a diurnal variation in tolerance to oral glucose loads has been consistently demonstrated [9][10][11][12][13][14], it has not been uniformly observed following consumption of mixed meals [15][16][17][18]. Furthermore, although glucose tolerance improVed following closely timed administration of successive intravenous or oral glucose loads [19,20], it deteriorated if a 3-h interval was allowed between successive glucose loads [21].…”

Fasting but not postprandial (postmeal) glycemia predicts the risk of death in subjects with coronary artery disease

“…To our knowledge, the present study was the first to examine the potential prognostic significance of 2hPG levels measured following an average meal. 2hPG measurements after a standardized meal have been shown to correlate with 2 h postchallenge glucose levels measured after an OGTT (21)(22)(23). In addition, IGT, as diagnosed during an OGTT, is a known risk factor for long-term mortality, as noted previously (11)(12)(13).…”

Gender differences in TNF-α levels among obese vs nonobese Latino children

“…Fasting plasma glucose, insulin, lipids, and TNF-a were determined from fasting baseline blood collection from a standardized oral glucose tolerance test (OGTT) administration (Owens et al, 1979). Enzyme-linked immunosorbance assay (ELISA) was used to determine fasting plasma TNF-a concentrations according to recommendations from the manufacturer (Immunotech, Beckman-Coulter, Westbrook, ME, USA), with standards assayed in duplicate.…”