A high protein low fat meal does not influence glucose and insulin responses in obese individuals with or without type 2 diabetes.
BACKGROUND
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.
Papakonstantinou
E
E
Department of Dietetics and Nutrition Sciences, Harokopio University, Athens, Greece.
Triantafillidou
D
D
Panagiotakos
D B
DB
Iraklianou
S
S
Berdanier
C D
CD
Zampelas
A
A
D001786:Blood Glucose; D048909:Diabetes Complications / Q000097:blood / Q000178:diet therapy*; D003924:Diabetes Mellitus, Type 2 / Q000097:blood / Q000150:complications / Q000178:diet therapy*; D018752:Diet, Fat-Restricted; D004044:Dietary Proteins / Q000008:administration & dosage*; D005260:Female; D006801:Humans; D007328:Insulin / Q000097:blood*; D007333:Insulin Resistance; D008297:Male; D008875:Middle Aged; D009765:Obesity / Q000097:blood / Q000150:complications / Q000178:diet therapy*; D019518:Postprandial Period; D016037:Single-Blind Method
D001786:Blood Glucose; D004044:Dietary Proteins; D007328:Insulin