Metabolic Effects of Reducing Rate of Glucose Ingestion by Single Bolus Versus Continuous Sipping

Abstract

Modifying the rate of absorption has been proposed as a therapeutic principle of specific relevance to diabetes. To demonstrate clearly the metabolic benefits that might result from reducing the rate of nutrient delivery, nine healthy volunteers took 50 g glucose in 700 ml water on two occasions: over 5-10 min (bolus) and at a constant rate over 3.5 h (sipping). Despite similar 4-h blood glucose areas, large reductions were seen in serum insulin (54 +/- 10%, P less than 0.001) and C-peptide (47 +/- 12%, P less than 0.01) areas after sipping, together with lower gastric inhibitory polypeptide and enteroglucagon levels and urinary catecholamine output. There was also prolonged suppression of plasma glucagon, growth hormone, and free-fatty acid (FFA) levels after sipping, whereas these levels rose 3-4 h after the glucose bolus. An intravenous glucose tolerance test at 4 h demonstrated a 48 +/- 10% (P less than 0.01) more rapid decline in blood glucose (Kg) after sipping than after the bolus. Furthermore, FFA and total branched-chain amino acid levels as additional markers of insulin action were lower over this period despite similar absolute levels of insulin and C-peptide. These findings indicate that prolonging the rate of glucose absorption enhances insulin economy and glucose disposal.

Glycemic index in chronic disease: a review

“…However, it has been shown that neither fat nor protein in the amounts found in most foods (with the exception of peanuts and most nuts) Lower postprandial glucose rise (Jenkins et al, 1990(Jenkins et al, ,1992Bertelsen et al, 1993;Jones et al, 1993) Reduced daily mean insulin levels (Jenkins et al, 1990(Jenkins et al, ,1992Bertelsen et al, 1993;Jones et al, 1993) Flatter gastric inhibitory polypeptide response (Jenkins et al, 1990(Jenkins et al, ,1992Bertelsen et al, 1993) Decreased 24 h urinary C-peptide output (Jenkins et al, 1989(Jenkins et al, ,1992 Prolonged suppression of plasma free fatty acids (Jenkins et al, 1990) Reduced urinary catecholamine output (Jenkins et al, 1990) Lower total and LDL cholesterol levels (Jenkins et al, 1989Arnold et al, 1993;Cohn 1964) Reduced hepatic cholesterol synthesis (Jones et al, 1993) Decreased serum apolipoprotein B levels (Jenkins et al, 1989) Decreased serum uric acid levels Raised urinary uric acid excretion Adapted from Jenkins et al (1995). Glycemic index in chronic disease LS Augustin et al significantly alters the glycemic response (Wolever et al, 1994).…”

The Influence of Legume Seeds on Human Plasma Lipid Concentrations

“…There is some evidence to suggest that plasma cholesterol and triacylglycerols are reduced when glucagon is present in excess of insulin (Lakshmanan et al 1973). Recently, Jenkins et al (1990) reported that a reduced rate of glucose ingestion was associated with reductions in the secretion of both glucagon and insulin. Although the ratio of the two hormones was not reported, the change in secretion of glucagon appeared to be less marked than that of insulin, and may have resulted in an increased g1ucagon:insulin ratio.…”

Metabolic correlates of eating behavior in severe obesity

“…Indeed, the dictionary de®nition of`gorging' involves both speed (`swallow with greediness') and amount or volume (`in large quantities'), though scienti®c papers using the term refer to both the number of meals 10,11,14 and the rate of ingestion. 12,15 Although eating rate differs between sexes, and between the lean and obese, 18 it has not been investigated in relation to body fat distribution or metabolic abnormalities associated with fat distribution. Therefore, we studied eating rate, fat distribution, 19 serum lipids and liver fat in severely obese subjects undergoing anti-obesity surgery and, in so doing, demonstrate relationships between eating behavior and metabolism which may contribute to the understanding of the metabolic syndrome of obesity.…”