Randomised controlled trial of the effects of L-ornithine on stress markers and sleep quality in healthy workers

Nutr J. 2014 Jun 3:13:53. doi: 10.1186/1475-2891-13-53.

Abstract

Background: L-ornithine is a non-essential, non-protein amino acid. Although L-ornithine is contained in various foods, the amount is usually small.Recently, studies have shown that orally administered L-ornithine reduced the stress response in animals.From these findings, we speculated that L-ornithine may play a role in the relieve of stress and improve sleep and fatigue symptoms in humans. Through a randomised, double-blind, placebo-controlled clinical study, we asked if L-ornithine could be beneficial to stress and sleep in healthy workers.

Method: Fifty-two apparently healthy Japanese adults who had previously felt slight stress as well as fatigue were recruited to be study participants and were randomly divided into either the L-ornithine (400 mg/day) or placebo group. They orally consumed the respective test substance every day for 8 weeks. Serum was collected for the assessment of cortisol and dehydroepiandrosterone-sulphate (DHEA-S). Perceived mood and quality of sleep were measured by the Profile of Mood States (POMS), Athens Insomnia Scale (AIS), and Ogri-Shirakawa-Azumi sleep inventory MA version (OSA-MA).

Results: Serum cortisol levels and the cortisol/DHEA-S ratio were significantly decreased in the L-ornithine group in comparison with the placebo group. Also, anger was reduced and perceived sleep quality was improved in the L-ornithine group.

Conclusion: L-ornithine supplementation has the potential to relieve stress and improve sleep quality related to fatigue, both objectively and subjectively.

Publication types

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

MeSH terms

  • Adult
  • Affect / drug effects*
  • Dehydroepiandrosterone Sulfate / blood
  • Dietary Supplements
  • Double-Blind Method
  • Fatigue / drug therapy*
  • Female
  • Humans
  • Hydrocortisone / blood
  • Male
  • Middle Aged
  • Ornithine / therapeutic use*
  • Placebos
  • Sleep / drug effects
  • Stress, Psychological / drug therapy*

Substances

  • Placebos
  • Dehydroepiandrosterone Sulfate
  • Ornithine
  • Hydrocortisone