Glutamine supplementation favors weight loss in nondieting obese female patients. A pilot study

Eur J Clin Nutr. 2014 Nov;68(11):1264-6. doi: 10.1038/ejcn.2014.184. Epub 2014 Sep 17.


Glutamine supplementation improves insulin sensitivity in critically ill patients, and prevents obesity in animals fed a high-fat diet. We hypothesized that glutamine supplementation favors weight loss in humans. Obese and overweight female patients (n=6) were enrolled in a pilot, cross-over study. After recording anthropometric (that is, body weight, waist circumference) and metabolic (that is, glycemia, insulinemia, homeostatic model of insulin resistance (HOMA-IR)) characteristics, patients were randomly assigned to 4-week supplementation with glutamine or isonitrogenous protein supplement (0.5 g/KgBW/day). During supplementation, patients did not change their dietary habits nor lifestyle. At the end, anthropometric and metabolic features were assessed, and after 2 weeks of washout, patients were switched to the other supplement for 4 weeks. Body weight and waist circumference significantly declined only after glutamine supplementation (85.0±10.4 Kg vs 82.2±10.1 Kg, and 102.7±2.0 cm vs 98.9±2.9 cm, respectively; P=0.01). Insulinemia and HOMA-IR declined by 20% after glutamine, but not significantly so. This pilot study shows that glutamine is safe and effective in favoring weight loss and possibly enhancing glucose metabolism.

Publication types

  • Randomized Controlled Trial

MeSH terms

  • Adult
  • Blood Glucose / metabolism
  • Body Mass Index
  • Body Weight
  • Critical Illness / therapy
  • Cross-Over Studies
  • Dietary Proteins / administration & dosage
  • Dietary Supplements*
  • Female
  • Glutamine / administration & dosage*
  • Humans
  • Insulin Resistance
  • Middle Aged
  • Obesity / drug therapy*
  • Overweight / drug therapy
  • Pilot Projects
  • Waist Circumference
  • Weight Loss*


  • Blood Glucose
  • Dietary Proteins
  • Glutamine