Effect of glutamine supplementation on cardiovascular risk factors in patients with type 2 diabetes

Nutrition. 2015 Jan;31(1):119-26. doi: 10.1016/j.nut.2014.05.014. Epub 2014 Jun 23.

Abstract

Objective: The aim of this study was to assess clinical relevance of long-term oral glutamine supplementation on lipid profile and inflammatory and metabolic factors in patients with diabetes.

Method: Sixty-six patients with type 2 diabetes between the ages of 18 and 65 y were randomized to receive glutamine 30 g/d (10 g powder, three times a day) or placebo, in a double-blind, placebo-controlled trial during a 6-wk treatment period. Fifty-three patients completed the trial. Independent samples t test and analysis of covariance were used.

Results: After a 6-wk treatment period, a significant difference was observed between the two groups in body fat mass (P = 0.01) and percentage of body fat (P = 0.008). Moreover, a significant reduction in waist circumference (P < 0.001) and a tendency for an increase in fat-free mass (P = 0.03), with no change in body weight and body mass index (BMI) was found. Enhancement in body fat-free mass was mainly attributed to trunk (P = 0.03). There was a downward trend in systolic blood pressure (P = 0.005) but not diastolic. Fasting blood glucose (mmol/L) concentration significantly decreased after the 6-wk intervention (P = 0.04). Mean hemoglobin A1c was significantly different between the groups at week 6 (P = 0.04). No significant difference was detected for fasting insulin, homeostasis model assessment for insulin resistance and quantitative insulin sensitivity index between groups (P > 0.05). No significant difference was observed between groups in total cholesterol, high-density lipoprotein cholesterol, low-density lipoprotein cholesterol and triglyceride. No treatment effect on C-reactive protein was found (P = 0.44).

Conclusion: We demonstrated that the 6-wk supplementation with 30 g/d glutamine markedly improved some cardiovascular risk factors, as well as body composition, in patients with type 2 diabetes. Future glutamine dose-response studies are warranted in these areas.

Keywords: Body composition; GLP-1; Glutamine supplementation; Insulin; Type 2 diabetes.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adipose Tissue / drug effects
  • Adipose Tissue / metabolism
  • Adult
  • Blood Glucose / metabolism
  • Blood Pressure / drug effects
  • Body Composition
  • Body Mass Index
  • C-Reactive Protein / metabolism
  • Cardiovascular Diseases / blood
  • Cardiovascular Diseases / prevention & control*
  • Cholesterol, HDL / blood
  • Cholesterol, LDL / blood
  • Diabetes Mellitus, Type 2 / blood
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Diet
  • Dietary Supplements*
  • Dose-Response Relationship, Drug
  • Double-Blind Method
  • Female
  • Glutamine / administration & dosage*
  • Glutamine / blood
  • Glycated Hemoglobin A / metabolism
  • Homeostasis
  • Humans
  • Insulin / blood
  • Insulin Resistance
  • Male
  • Middle Aged
  • Motor Activity
  • Risk Factors
  • Triglycerides / blood

Substances

  • Blood Glucose
  • Cholesterol, HDL
  • Cholesterol, LDL
  • Glycated Hemoglobin A
  • Insulin
  • Triglycerides
  • Glutamine
  • C-Reactive Protein