Effect of oral supplementation of free amino acids in type 2 diabetic patients-- a pilot clinical trial

Med Sci Monit. 2002 Mar;8(3):CR131-7.


Background: Oral amino acid intake reduces plasma glucose in Streptozotocin-induced diabetic rats. This study examined the effect of oral amino acid supplementation in patients with type 2 diabetes mellitus (DM).

Material/methods: A double blind pilot clinical trial was conducted for a period of 2 months on 77 subjects with type 2 DM. Subjects of both sexes, ages 30-60, were included in the trial. All were receiving oral antidiabetic tablets. They were divided into groups on the basis of oral supplementation: (A) lysine, (B) essential amino acids, (C) amino acids and vitamins (fat and water-soluble), and (D) calcium phosphate (control). The subjects were periodically examined for fasting and post-prandial plasma glucose, fasting and post-prandial immunoreactive insulin, plasma amino acids, glycosylated haemoglobin (HbA1c), proteins and albumin in serum, urea and creatinine in plasma and sugar, and proteins and ketones in urine.

Results: The results revealed a significant decrease in PP plasma glucose (P<0.05) in group B when compared to groups C and D after 45 days. Plasma Arginine was increased in group C from 3.84 to 9.24 mg/dl. There were no statistically significant changes seen in other parameters between groups and visits.

Conclusions: Oral supplementation with amino acids for patients with type 2 DM appears to decrease PP plasma glucose without any change in plasma insulin levels, perhaps due to improved insulin sensitivity. However, the long term effects of amino acids need further study.

Publication types

  • Clinical Trial
  • Controlled Clinical Trial

MeSH terms

  • Administration, Oral
  • Adult
  • Amino Acids / administration & dosage*
  • Amino Acids / metabolism
  • Amino Acids / therapeutic use*
  • Antioxidants / metabolism
  • Blood Glucose / metabolism
  • Body Mass Index
  • Diabetes Mellitus, Type 2 / drug therapy*
  • Double-Blind Method
  • Female
  • Humans
  • Insulin / blood
  • Lysine / metabolism
  • Male
  • Middle Aged
  • Pilot Projects


  • Amino Acids
  • Antioxidants
  • Blood Glucose
  • Insulin
  • Lysine