Effect of meal size and texture on gastric pouch emptying and glucagon-like peptide 1 after gastric bypass surgery

Abstract

Background Roux-en-Y gastric bypass (RYGB) accelerates gastric pouch emptying, enhances postprandial glucagon-like peptide 1 (GLP-1) and insulin, and lowers glucose concentrations. To prevent discomfort and reactive hypoglycemia, it is recommended that post-RYGB patients eat small, frequent meals and avoid caloric drinks. However, the effect of meal size and texture on GLP-1 and metabolic response has not been studied. Objectives To demonstrate that frequent minimeals and solid meals (S) elicit less GLP-1 and insulin release and less reactive hypoglycemia and are better tolerated compared with a single isocaloric liquid meal (L). Setting A university hospital. Methods In this prospective study, 32 RYGB candidates were enrolled and randomized to L or S groups before gastric bypass. Each subject received an L or S 600-kcal single meal (SM) administered at hour 0 or three 200-kcal minimeals administered at hours 0, 2, and 4 on 2 separate days. Twenty-one patients were retested 1 year after RYGB. Blood and visual analogue scale measurements were collected up to 6 hours postprandially. Outcome measures included gastric pouch emptying, glucose, insulin, and GLP-1; hunger, fullness, and stomach discomfort were measured by visual analogue scale. Results Twenty-one were patients retested after RYGB (L: n = 12; S: n = 9). Meal texture had a significant effect on peak GLP-1 (L-SM: 106.1 ± 67.2 versus S-SM: 45.3 ± 25.2 pM, P = .004), peak insulin, and postprandial glucose. Hypoglycemia was more frequent after the L-SM meal compared with the S-SM. Gastric pouch emptying was 2.4 times faster after RYGB but was not affected by texture. Conclusions Meal texture and size have significant impact on tolerance and metabolic response after RYGB.

Postprandial hypoglycaemia after Roux‐en‐Y gastric bypass and the effects of acarbose, sitagliptin, verapamil, liraglutide and pasireotide

“…We did not measure intact GLP‐1 or GIP, but neither did we find any significant differences in insulin levels, C‐peptide levels or ISRs to support this argument; however, the insulin‐to‐glucose ratio was increased at both 45 and 60 minutes after meal intake. Hyperglycaemia was reduced in the CGM recordings but not in the MMTTs, an observation that could be explained by differences in meal texture and meal size composition during the CGM periods …”

“…Possibly, the pasireotide‐induced hyperglycaemia would be less pronounced following smaller, solid meals as recommended for people who have undergone RYGB. The differences in hypoglycaemia rates recorded during the MMTT and the CGM periods may be related to differences in meal texture and size, as liquid meals more frequently trigger hypoglycaemia . Most importantly, glucose variability and hypoglycaemia are influenced by dietary intake, especially carbohydrates, which was not evaluated in the present study, although the participants were instructed to adhere to their usual diet.…”

“…The differences in hypoglycaemia rates recorded during the MMTT and the CGM periods may be related to differences in meal texture and size, as liquid meals more frequently trigger hypoglycaemia. 37 Most importantly, glucose variability and hypoglycaemia are influenced by dietary intake, especially carbohydrates, which was not evaluated in the present study, although the participants were instructed to adhere to their usual diet. The frequency and severity of hypoglycaemic symptoms were not assessed and thus we cannot conclude on the subjective treatment effects.…”

“…Hyperglycaemia was reduced in the CGM recordings but not in the MMTTs, an observation that could be explained by differences in meal texture and meal size composition during the CGM periods. 37 Insulin secretion from the β cells is activated through Ca 2+ influx to the intracellular compartment, and calcium antagonism has been associated with reduced insulin secretion and elevated glucose levels in patients with insulinomas. 11 In individuals with PBH, treatment with calcium channel blockers was reported to improve hypoglycaemic symptoms, but these observations were not supported by blood glucose measurements.…”

Hypoglycemia After Gastric Bypass Surgery: Current Concepts and Controversies

“…Dietary carbohydrate composition and food texture can also influence postprandial metabolism (43), but the optimal plan for long-term therapy has not been well defined. Our clinical experience indicates that a meal plan focused on elimination of simple sugars but including controlled portions of low glycemic index carbohydrates with multiple small meals and snacks containing up to 30 and 15 g, respectively (i.e., 90 to 130 g/d), is usually well tolerated and often helpful in reducing hypoglycemia.…”