A very low-calorie diet improved insulin sensitivity and secretion similarly to gastric bypass in patients with type 2 diabetes, according to data presented at the 2012 Obesity Society Annual Meeting.
The study included 11 patients who underwent Roux-en-Y gastric bypass (RYGB) and 11 who began a 500 kcal per day diet (VLCD). Researchers performed intravenous glucose tests before and after initiation of surgery or diet, and also compared changes to insulin sensitivity, responses to glucose and disposition index between the groups.
At baseline, both groups had similar characteristics, including the mean duration of diabetes (5.7 years), BMI (41.4 kg/m2), fasting glucose levels (195 mg/dl) and HbA1c (8.4%). Participants lost a mean of 8.0% of their body weight over 3.4 weeks after surgery or while on the VLCD. Both groups experienced the following increases to insulin sensitivity, response to glucose and disposition index, all of which were considered statistically significant (P<.05 for all):
- Sensitivity: From 1.4 to 2.2 in the RYGB group; from 1.3 to 2.2 in the VLCD group
- Acute insulin response to glucose: From 19.8 to 86.9 in the RYGB group; from 13.0 to 84.8 in the VLCD group
- Disposition index: From 8.2 to 195.8 in the RYGB group; from 12.9 to 172.6 in the VLCD group
Differences between the two groups in degree of change were not found statistically significant for any of these factors.
“There were significant and similar improvements in glucostatic parameters after VLCD and RYGB,” the researchers concluded. “Additional subjects are currently being studied to confirm these findings.”
For more information:
Jackness CM. #32-OR: Changes in Insulin Sensitivity and Secretion in Patients With T2DM After Weight Loss Induced By Roux-en-Y Gastric Bypass or Equivalent Caloric Restriction. Presented at: the 2012 Obesity Society Annual Scientific Meeting; Sept. 20-24, San Antonio.