Written by Greg Arnold, DC, CSCS. L-ornithine supplementation was shown to improve both fatigue and stress in this study.
Sleep is both necessary and universal and affects both immune system function and hormone levels (1, 2). Loss of sleep and mental stress lead to fatigue and can, in the worst case scenario, cause death as has been seen in Japan in the form of karoshi (“death from overwork”) (3).
Now a new study (4) suggests that the amino acid L-ornithine may help with both fatigue and stress and even affect blood levels of stress hormones. In the study, 52 healthy Japanese adults (21 men, 32 women) between the ages 41 of 45 were given either 400 milligrams per day of L-ornithine or placebo for 8 weeks. Blood samples were taken before and after the study to measure for the stress hormones cortisol and dehydroepiandrosterone-sulphate (DHEA-S) while each subject also completed a stress survey called the Profile of Mood States (5) and 2 sleep survey, the Athens Insomnia Scale (6), and Ogri-Shirakawa-Azumi sleep inventory MA version (7).
The researchers found significant decreases in anger-hostility at weeks 2 and 6 (but not week 8):
| L-Ornithine | Placebo | p value | |
|---|---|---|---|
| Anger-hostility at start of study | 63.31 | 61.85 | |
| Week 2 | 54.31 (14.3% decrease) | 57.85 (6.5% decrease) | < 0.001 |
| Week 6 | 50.31 (20.6% decrease) | 57.85 (6.5% decrease) | < 0.05 |
and significant improvement in overall score on the Athens Insomnia Scale and week 4 as well as initiation and maintenance of sleep at week 4 (but not week 8):
| L-Ornithine | Placebo | p-value | |
|---|---|---|---|
| Athens Insomnia Scale overall score - start of study | 8.54 | 7.96 | |
| Week 4 | 8.54 (47.9% decrease) | 5.66 (28.9% decrease) | < 0.05 |
| Initiation/maintenance of sleep at start of study | 12.12 | 15.21 | |
| Week 4 | 20.12 (66% increase) | 19.21 (26.3% increase) | < 0.05 |
And while no statistically significant decreases were seen with individual levels of cortisol or DHEA-S, a statistically significant decrease was seen with their ratio (thought to be more reliable than individual levels (8)) at week 4:
| L-Ornithine | Placebo | p-value | |
|---|---|---|---|
| Cortisol/DHEA-S ratio - start of study | 5.67 | 7.96 | |
| Week 4 | 4.67 (17.7% decrease) | 7.76 (2.6% decrease) | < 0.05 |
While the researchers did not discuss why statistical significance was not reached at week 8, they concluded that “L-ornithine supplementation has the potential to relieve stress and improve sleep quality related to fatigue, both objectively and subjectively.” Caution should be taken as this study was done in a homogenous population of Japanese residents in Japan and may not be the same in a population of Americans.
Source: Miyake, Mika, Takayoshi Kirisako, Takeshi Kokubo, Yutaka Miura, Koji Morishita, Hisayoshi Okamura, and Akira Tsuda. “Randomised controlled trial of the effects of L-ornithine on stress markers and sleep quality in healthy workers.” Nutrition journal 13, no. 1 (2014): 53.
© Miyake et al.; licensee BioMed Central Ltd. 2014
References:
- Cohen S, Doyle WJ, Alper CM, Janicki-Deverts D, Turner RB: Sleep habits and susceptibility to the common cold. Arch Intern Med 2009, 169:62–67
- Irwin M, Clark C, Kennedy B, Christian Gillin J, Ziegler M: Nocturnal catecholamines and immune function in insomniacs, depressed patients, and control subjects. Brain Behav Immun 2003, 17:365–372
- Nishiyama K, Johnson JV: Karoshi–death from overwork: occupational health consequences of Japanese production management. Int J Health Serv 1997, 27:625–641
- Miyake M. 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
- McNair P, Lorr M, Droppleman L: Profile of Mood States. San Diego: Educational and Industrial Testing Service; 1992.
- Yamamoto Y, Tanaka H, Takase M, Shirakawa S: Standardization of revised version of OSA sleep inventory for middle age and aged. Brain Sci Ment Disord 1999, 10:401–409
- Soldatos CR, Dikeos DG, Paparrigopoulos TJ: Athens Insomnia Scale: validation of an instrument based on ICD-10 criteria. J Psychosom Res 2000, 48:555–560
- Michael A, Jenaway A, Paykel ES, Herbert J: Altered salivary dehydroepiandrosterone levels in major depression in adults. Biol Psychiatry 2000, 48:989–995
