A high protein low fat meal does not influence glucose and insulin responses in obese individuals with or without type 2 diabetes

J Hum Nutr Diet. 2010 Apr;23(2):183-9. doi: 10.1111/j.1365-277X.2009.01020.x. Epub 2010 Jan 22.

Abstract

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.

Publication types

  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Blood Glucose*
  • Diabetes Complications / blood
  • Diabetes Complications / diet therapy*
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / complications
  • Diabetes Mellitus, Type 2 / diet therapy*
  • Diet, Fat-Restricted*
  • Dietary Proteins / administration & dosage*
  • Female
  • Humans
  • Insulin / blood*
  • Insulin Resistance
  • Male
  • Middle Aged
  • Obesity / blood
  • Obesity / complications
  • Obesity / diet therapy*
  • Postprandial Period
  • Single-Blind Method

Substances

  • Blood Glucose
  • Dietary Proteins
  • Insulin