A high protein low fat meal does not influence glucose and insulin responses in obese individuals with or without type 2 diabetes
When substituted for carbohydrate in a meal, dietary protein enhances glycaemic control in subjects with type 2 diabetes (DM2). It is unknown whether the effect is a result of increased protein or reduced carbohydrate. The present study aimed to compare the effects of two meals differing in protein to fat ratios on post-prandial glucose and insulin responses. Methods:
This was a crossover, blind study in which obese subjects with (n = 23) and without (n = 26) DM2 consumed two meals in random order with equal amounts of energy (3.1 MJ, 741 kcal), fibre and carbohydrates and a 1-week washout period. Meals were a high protein, low fat (30% protein, 51% carbohydrates, 19% fat) meal and a low protein, high fat (15% protein, 51% carbohydrates, 34% fat) meal. Subjects were matched for age and body mass index. Plasma glucose and insulin were measured at fasting, 30, 60, 90, 120 min post-prandially. Insulin resistance and insulin sensitivity were assessed. Results:
There was no significant meal effect on glucose and insulin responses within groups. Glucose response was higher in diabetic (120 min 11 ± 0.7 mmol L−1) compared to nondiabetic (120 min 5 ± 0.2; P < 0.001) subjects. Diabetic subjects had significantly higher insulin resistance (P < 0.001) and lower insulin sensitivity (P < 0.001) than nondiabetics. Although peak insulin levels, 60 min post-prandially, did not differ between groups (81 ± 9 pmol L−1 for diabetic versus 79 ± 7 pmol L−1 for nondiabetic subjects), they were achieved much later, 90 min post-prandially, in diabetic, (99 ± 8 pmol L−1) compared to nondiabetic (63 ± 7 pmol L−1, P = 0.002) subjects. Conclusions:
Manipulating protein to fat ratio in meals does not affect post-prandial plasma blood glucose or insulin responses in obese people with and without DM2.
Document Type: Research Article
Affiliations: 1: Tzanio General Hospital, Piraeus, Greece 2: Department of Dietetics and Nutrition Sciences, Harokopio University, Athens, Greece 3: University of Georgia, Athens, GA, USA 4: Unit of Human Nutrition, Department of Food Science and Technology, Agricultural University of Athens, Athens, Greece
Publication date: April 1, 2010