A protein-enriched low glycemic index diet with omega-3 polyunsaturated fatty acid supplementation exerts beneficial effects on metabolic control in type 2 diabetes

Prim Care Diabetes. 2014 Dec;8(4):308-14. doi: 10.1016/j.pcd.2014.02.004. Epub 2014 Mar 19.


Aims: The current study aims to investigate practicability and effects of a combined dietary intervention with increased relative protein content supplemented with omega-3 polyunsaturated fatty acids (PUFA) on metabolic control and inflammatory parameters in a real life situation in type 2 diabetes patients.

Methods: In this observational study we advised thirty mostly obese patients with type 2 diabetes to follow a protein-enriched diet with carbohydrates of low glycemic index (low GI) and moderate fat reduction supplemented with omega-3 PUFA for 24 weeks. Primary efficacy parameter was the change in HbA1c; secondary parameters included changes in systemic inflammation (measured by ultrasensitive C-reactive protein, usCRP), body weight, waist circumference, fat mass. The study is registered at clinicaltrials.gov (NCT01474603).

Results: The dietary intervention significantly reduced the primary efficacy variable HbA1c from a baseline value of 63±11mmol/mol to 59±14mmol/mol (P=0.033) and 56±12mmol/mol (P=0.001) after 12 and 24 weeks, respectively. In addition, usCRP decreased significantly at 24 weeks (P=0.039). Waist circumference, an important indicator for cardiometabolic-risk and silent inflammation, decreased from baseline 116.0±14.1cm to 114.9±13.5cm (P=0.019), 114.0±14.4cm (P=0.001), and 112.7±13.4cm (P=0.049), after 3, 12 and 24 weeks, respectively.

Conclusion: Counseling a protein enriched and low glycemic index diet supplemented with long-chain omega-3 PUFA in a real-life clinical setting improves glycemic control and also reduces waist circumference and silent inflammation in overweight or obese patients with type 2 diabetes.

Keywords: Diabetes mellitus type 2; Dietary protein; Inflammation; Low GI diet; Metabolic control; Omega-3 polyunsaturated fatty acids.

Publication types

  • Clinical Trial
  • Observational Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adiposity
  • Adult
  • Aged
  • Austria
  • Biomarkers / blood
  • Body Mass Index
  • C-Reactive Protein / metabolism
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / diagnosis
  • Diabetes Mellitus, Type 2 / diet therapy*
  • Diabetes Mellitus, Type 2 / etiology
  • Diet, Fat-Restricted
  • Dietary Carbohydrates / administration & dosage*
  • Dietary Proteins / administration & dosage*
  • Dietary Supplements*
  • Energy Metabolism*
  • Fatty Acids, Omega-3 / administration & dosage*
  • Female
  • Glycated Hemoglobin A / metabolism
  • Glycemic Index*
  • Humans
  • Inflammation Mediators / blood
  • Male
  • Middle Aged
  • Obesity / blood
  • Obesity / complications
  • Obesity / diet therapy*
  • Pilot Projects
  • Time Factors
  • Treatment Outcome
  • Waist Circumference
  • Weight Loss


  • Biomarkers
  • Dietary Carbohydrates
  • Dietary Proteins
  • Fatty Acids, Omega-3
  • Glycated Hemoglobin A
  • Inflammation Mediators
  • hemoglobin A1c protein, human
  • C-Reactive Protein

Associated data

  • ClinicalTrials.gov/NCT01474603