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OBJECTIVE To compare the effect of an isocaloric multifactorial diet with a diet rich in monounsaturated fatty acids (MUFA) and similar macronutrient composition on pancreatic fat (PF) and postprandial insulin response in type 2 diabetes (T2D). RESEARCH DESIGN AND METHODS According to a randomized controlled parallel-group design, 39 individuals with T2D, 35–75 years old, in satisfactory blood glucose control, were assigned to an 8 week isocaloric intervention with a multifactorial diet rich in MUFA, polyunsaturated fatty acids, fiber, polyphenols, and vitamins (n = 18) or a MUFA-rich diet (n = 21). Before/after the intervention, PF content was measured by the proton-density fat fraction using a three-dimensional mDIXON MRI sequence, and plasma insulin and glucose concentrations were measured over a 4 h test meal with a similar composition as the assigned diet. RESULTS After 8 weeks, PF significantly decreased after the multifactorial diet (from 15.7 ± 6.5% to 14.1 ± 6.3%; P = 0.024), while it did not change after the MUFA diet (from 17.1 ± 10.1% to 18.6 ± 10.6%; P = 0.139) with a significant difference between diets (P = 0.014). Postprandial glucose response was similar in the two groups. Early postprandial insulin response (incremental postprandial areas under the curve [iAUC0–120]) significantly increased with the multifactorial diet (from 36,340 ± 34,954 to 44,138 ± 31,878 pmol/L/min; P = 0.037), while it did not change significantly in the MUFA diet (from 31,754 ± 18,446 to 26,976 ± 12,265 pmol/L/min; P = 0.178), with a significant difference between diets (P = 0.023). Changes in PF inversely correlated with changes in early postprandial insulin response (r = −0.383; P = 0.023). CONCLUSIONS In patients with T2D, an isocaloric multifactorial diet, including several beneficial dietary components, markedly reduced PF. This reduction was associated with an improved postprandial insulin response.

Achieving optimal postprandial glucose control remains a major issue in people with type 1 diabetes (T1D), including those using innovative technologies (1,2). Eating pizza is challenging for patients with T1D (3) because of its high and extremely variable glycemic index (4) and prolonged postprandial hyperglycemia. Bread leavened by sourdough instead of brewer’s yeast may reduce postprandial glucose response (PGR), and duration of sourdough leavening could play a beneficial role (5). Whether this holds true for pizza and in patients with T1D is unknown. We compared PGR for pizzas differing in type and duration of dough leavening in 16 T1D patients (9 men, 7 women) on an insulin pump. The study was approved by the institutional ethics committee (reg. no. NCT03619031, ClinicalTrials.gov). According to a randomized crossover design, participants consumed—at home, on three nonconsecutive evenings over 3 weeks—a pizza prepared with 1 ) brewer’s yeast and wheat flour, 5-h leavening (usual leavening time) (Brew5); 2 ) sourdough and flour mix, 5-h leavening (Sour5); or 3 ) sourdough and flour mix, 60-h leavening (Sour60). Premeal insulin doses, calculated by the individual insulin–to–glycemic load ratio (2) (the same for each participant on the three occasions, range 6–14 IU) were given as an 80/20% dual-wave bolus extended for 4 h. PGR was evaluated by the real-time continuous glucose monitoring system (Dexcom, Guardian, or Freestyle) used by …

OBJECTIVE To evaluate whether fat quality, in the context of meals with high– (HGI) or low–glycemic index (LGI), influences postprandial blood glucose (PPG) response in patients with type 1 diabetes. RESEARCH DESIGN AND METHODS According to a randomized crossover design, 13 patients with type 1 diabetes on insulin pump consumed two series (HGI or LGI) of meals with the same carbohydrate quantity while differing for amount and quality of fat: 1) low in fat (“low fat”), 2) high in saturated fat (butter), or 3) high in monounsaturated fat (extra-virgin olive oil) (EVOO). Premeal insulin doses were based on insulin–to–glycemic load ratios. Continuous glucose monitoring was performed and 6-h PPG evaluated. RESULTS PPG was significantly different between HGI and LGI meals (P = 0.005 for time × glycemic index interaction by repeated-measures analysis [RMA]), being significantly higher during the first 3 h after the HGI meals with a later tendency to an opposite pattern. In the context of HGI meals, PPG was significantly lower after EVOO than after low fat or butter (P < 0.0001 for time × meal interaction by RMA), with a marked difference in the 0- to 3-h glucose incremental area under the curve between EVOO (mean ± SD 198 ± 274 mmol/L × 180 min) and either low fat (416 ± 329) or butter (398 ± 355) (P < 0.05). No significant differences were observed in PPG between the three LGI meals. CONCLUSIONS Carbohydrate quality of a mixed meal influences shape and extent of PPG. Besides, using EVOO in a HGI meal attenuates the early postprandial glucose response observed when this meal is consumed with either low fat or butter. Therefore, an optimal prandial insulin administration would require considering, in addition to the quantity of carbohydrates, the quality of both carbohydrate and fat.