Biomedical subjects

J H Lavin

Publications and source records attributed to J H Lavin.

At least 19 recordsLinked to original sources

PubMed1998

Interaction of insulin, glucagon-like peptide 1, gastric inhibitory polypeptide, and appetite in response to intraduodenal carbohydrate.

The relation between gastrointestinal incretin hormones in the control of insulin release and short-term satiety by intestinal carbohydrate was investigated in 8 fasted, healthy male volunteers. Insulin, gastric inhibitory polypeptide (GIP), glucagon-like peptide 1 (GLP-1), and appetite ratings were measured during, and food intake was measured after, intraduodenal infusions of glucose or saline. Studies were conducted under hyperinsulinemic and euglycemic conditions. Raising plasma insulin with intravenous insulin infusion to concentrations slightly above usual postprandial concentrations (356.4 +/- 4.8 pmol/L) had no effect on GIP, GLP-1, or appetite ratings before the intraduodenal infusions began. Intraduodenal glucose infusion resulted in a further increase in plasma insulin to a peak of 779.4 +/- 114.0 pmol/L, caused an early increase in plasma GIP and a later increase in GLP-1 concentrations (P < 0.01), suppressed appetite (P < 0.05), and reduced energy intake (P < 0.01) compared with intraduodenal infusion of saline. There was a close association between the increase in GLP-1 and decrease in appetite. Infusion of octreotide to suppress the release of gastrointestinal hormones prevented the rise in insulin, GIP, and GLP-1 induced by intraduodenal glucose infusion and reversed the suppression of appetite and reduction in energy intake. These results suggest that 1) when infused to result in plasma concentrations slightly above usual postprandial concentrations, insulin does not inhibit its own release and 2) the effects of intraduodenal glucose on appetite may be mediated through the release of GLP-1 and not insulin.

Adult↗

PubMed1997

The effect of sucrose- and aspartame-sweetened drinks on energy intake, hunger and food choice of female, moderately restrained eaters.

OBJECTIVE: To compare the effects of aspartame-sweetened and sucrose-sweetened soft drinks on food intake and appetite ratings of female restrained eaters. SUBJECTS: Fourteen female students, shown to have eating restraint. METHODS: Subjects were given four drinks (330 ml) of aspartame-sweetened lemonade, sucrose-sweetened lemonade and carbonated mineral water on three separate days. Seven of the subjects were informed of the drink type they were consuming on each occasion. MEASUREMENTS: Appetite ratings were recorded and energy and macronutrient intakes were measured during the study day and day after leaving the department. RESULTS: During the first study day energy intake was lower whilst drinking the sucrose-sweetened lemonade compared with the aspartame-sweetened lemonade, although neither differed significantly from energy intakes during the day the drank water. When the calories from the sucrose-sweetened lemonade were included (1381 kJ, 330 Kcal) energy intake did not differ between treatments. The following day energy intake was significantly higher after the aspartame-sweetened lemonade compared with both sucrose-sweetened lemonade and the water due to an increase in the amount of carbohydrate consumed and resulted in a higher total energy intake over the two days studied. Knowledge of the drink types had no effect on energy intake or macronutrient intake. Appetite ratings did not differ between drinks and were not affected by knowledge of the drink types. CONCLUSION: These results suggest that in females with eating restraint, substituting sucrose-sweetened drinks for diet drinks does not reduce total energy intake and may even result in a higher intake during the subsequent day.

Analysis of Variance↗

PubMed1996

Appetite regulation by carbohydrate: role of blood glucose and gastrointestinal hormones.

To investigate the mechanisms by which intestinal carbohydrate affects eating behavior, seven fasted, healthy male volunteers received intraduodenal infusions of glucose or saline over a 90-min period while blood glucose levels were matched by use of intravenous glucose and saline infusions. A second study examined the effect of intraduodenal glucose on eating behavior when the gastrointestinal hormone response was inhibited by intravenous octreotide. Intravenous glucose infusion did not affect hunger or satiety. In contrast, intraduodenal infusion of glucose suppressed hunger, increased fullness and satiety ratings, reduced energy intake, and resulted in higher plasma insulin responses compared with the intravenous glucose infusion. Octreotide abolished the plasma insulin response to intraduodenal glucose and reversed the changes in ratings and eating behavior. This study has shown that the effects of intestinal glucose on appetite are not mediated via an increase in blood glucose but are likely to reflect small intestinal stimulation of release of either insulin or intestinal incretins.

Adult↗

PubMed1995

The effect on hunger and satiety of slowing the absorption of glucose: relationship with gastric emptying and postprandial blood glucose and insulin responses.

To investigate the relative potency of short-term control mechanisms for carbohydrate satiety, ten fasted, healthy male volunteers consumed a 250-ml, 30% glucose drink with and without the addition of guar gum (2%). Gastric emptying, hunger and fullness ratings and blood glucose and insulin levels were monitored over the following 3 h and energy intake was recorded from a test meal given 3.5 h after the drinks. The addition of the guar gum to the glucose drink lowered both postprandial glucose and insulin levels over the following 2 h. This was associated with a reduction in the ratings for hunger and desire to eat and an increase in ratings for fullness and satiety, but energy intake from the test meal was unchanged. There was no difference between values for the half time for gastric emptying for the two drinks. The short-term increase in satiety and decrease in hunger seen when glucose absorption was slowed with guar gum is unlikely to be explained by the reduction in postprandial glycaemia or differences in gastric emptying, and instead may implicate increased contact of the carbohydrate with receptors in the small intestine and consequent enhanced release of putative satiety peptides.

Adult↗

PubMed1985