In a Free-Living Setting, Obesity Is Associated with Greater Food Intake in Response to a Similar Pre-Meal Glucose Nadir.

PURPOSE: Changes in blood glucose levels have been shown to influence eating in healthy individuals; however, less is known about glucose's effects on food intake in obese (OB) individuals. The goal of this study was to determine the predictive effect of circulating glucose levels on eating in free-living OB and normal weight (NW) individuals.

METHODS: Interstitial glucose levels, measured with a continuous glucose monitor (CGM) system, were obtained from 15 OB and 16 NW volunteers (age: 40±14, 37±12 yr; weight: 91±13, 68±12 kg; HbA1c: 5.1±0.7, 5.2±0.4%, respectively). While wearing the CGM participants filled up a food log (meal time, hunger rating and amount of food). Glucose profiles were measured in relation to their meals (macro program (CGM Peak and Nadir Analysis (CPNA)) in Microsoft® Excel).

RESULTS: OB and NW individuals showed comparable CGM glucose levels: mean (OB=99±13, NW=100±8 mg/dL, p=NS) and standard deviation (OB=18±4, NW=18±5 mg/dL, p=NS). Obesity was associated with slower post-prandial rate of changing glucose levels (p=0.04). Pre-prandial nadir glucose levels predicted hunger and food intake in both groups (p<0.0001), although hunger was associated with greater food intake in OB, in comparison to NW individuals (p=0.008 for group interaction).

CONCLUSIONS: Pre-meal glucose nadir predicted hunger and food intake in a group of free-living healthy non-diabetic NW and OB individuals, however for a similar low glucose level stimulus, greater hunger-induced food intake was recorded by OB in comparison to NW individuals.