Extra-Virgin Olive Oil Reduces Glycemic Response to a High-Glycemic Index Meal in Patients With Type 1 Diabetes: A Randomized Controlled Trial.
Diabetes Care. 2016 Feb 9. Epub 2016 Feb 9. PMID: 26861923
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 (extravirgin 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 ± 273 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 an 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.