Many people have difficulty sleeping in the summertime. This probably happens because the shorter day length makes us more active. Japanese researchers at the University of Kagoshima and the amino-acid manufacturer Kyowa Hakko Bio published the results of a study which you can interpret as suggesting that ornithine supplementation may offer some help.
Many people have difficulty sleeping in the summertime. This probably happens because the shorter day length makes us more active. Japanese researchers at the University of Kagoshima and the amino-acid manufacturer Kyowa Hakko Bio [kyowahakko-bio.co.jp] published the results of a study which you can interpret as suggesting that ornithine supplementation may offer some help.
Kyowa Hakko is part of Kirin, a division of Mitsubishi. Within the Kirin Holdings Company a Functional Food Business Project developed an interest in the effects of ornithine on sleep. For example, the project was involved in a human study that was published in spring 2013 in BioPsychoSocial Medicine [Biopsychosoc Med. 2013 Feb 18;7(1):6.], in which researchers studied the effect of ornithine on sleep after alcohol use.
Many people have difficulty sleeping in the summertime. This probably happens because the shorter day length makes us more active. Japanese researchers at the University of Kagoshima and the amino-acid manufacturer Kyowa Hakko Bio published the results of a study which you can interpret as suggesting that ornithine supplementation may offer some help.
The researchers got their subjects to drink alcohol in the evening, and then gave them a capsule containing 400 mg ornithine or a placebo. They discovered that the amino acid reduced the concentration of the stress hormone cortisol the following day. In the figure on the right the black bars represent the subjects who had taken ornithine.
The researchers used a standardised questionnaire to ascertain from the subjects the following day how well they had slept. The ornithine users reported feeling significantly less fatigue than the placebo users and they also reported less lassitude.
In July 2013 another study was published by the same group on the effect of ornithine on sleep. The subjects this time were the members of a Japanese expedition to Antarctica. They spent three months at the South Pole after arriving in December. So it was summertime there and the sun never set.
During their stay the placebo users reported that the quality of their sleep deteriorated. The ornithine users, who took 400 mg ornithine every day for two months, reported that their sleep quality remained stable. At the end of the two months they reported that their quality of sleep had actually improved.
The researchers are still puzzling over the mechanism at work here. They suspect that the ornithine administration meant that the brain was supplied with more serotonin, but this theory was not supported by blood tests carried out on the subjects.
A few years ago we wrote about an experiment done by the biochemist Mohamed Gad, who gave his test subjects a nightcap of 5 g L-arginine. Arginine is a metabolite of ornithine. The subjects’ health improved on all fronts: they started to feel noticeably better and reported that they slept better too.
Ornithine ingestion improved sleep disturbances but was not associated with correction of blood tryptophan ratio in Japanese Antarctica expedition members during summer.
Horiuchi M, Kanesada H, Miyata T, Watanabe K, Nishimura A, Kokubo T, Kirisako T.
Source
Department of Environmental Medicine, Kagoshima University Graduate School of Medical and Dental Sciences, Kagoshima, Japan.
Abstract
Members of expeditions to Antarctica may show changes in biological and physiological parameters involved in lipid, glucose, and thyroid hormone metabolism as they adapt to the environment; however, alterations in amino acid (AA) levels and sleep among expedition members in Antarctica have yet to be fully elucidated. We hypothesized that there would be alterations of blood AA levels, and ornithine (Orn) ingestion would affect biological parameters and sleep in Japanese expedition members during the summer in Antarctica. Japanese Antarctica Research Expedition members (22 people) who stayed in Antarctica for 3 months from December 2010 were examined, and a randomized double-blind study of Orn ingestion (400 mg/d) for 4 weeks was performed. Sleep conditions were evaluated subjectively by the Oguri-Shirakawa-Azumi (brief version) questionnaire. The blood of Japanese Antarctica Research Expedition members in Antarctica showed higher creatine kinase, lactate dehydrogenase, and ammonia levels than that in Japan. On blood AA analysis, aspartate, Orn, and serine were significantly higher, and alanine and tryptophan (Trp) were significantly lower in Antarctica than in Japan. The Trp ratio, the value of Trp divided by the sum of phenylalanine, tyrosine, and branched-chain AAs, was significantly lower in Antarctica than in Japan. Although sleep deteriorated during the stay in Antarctica, Orn ingestion, to some extent, improved sleep compared with the placebo group in Antarctica, suggesting that Orn is effective for people with heavy physical workloads in places such as Antarctica.
Copyright © 2013 Elsevier Inc. All rights reserved.
PMID: 23827130 [PubMed – in process]
