Chronic use of lots of glutamine could mess with your head
One page on PainSci cites Garlick 2001: Vitamins, Minerals & Supplements for Pain & Healing
PainSci notes on Garlick 2001:
Four studies of the safety of glutamine supplementation in a medical context found that it was “safe in adults and in preterm infants,” but that data was not relevant to concerns about “chronic consumption by healthy subjects.” The authors reviewed more literature on high dietary intake of proteins and amino acids in general, and found more problems, particularly neurological damage in preterm infants. Infants are particularly sensitive to neurological effects, so if they have problems, it certainly means trouble for adults too — just less dramatically. “Because glutamine is metabolized to glutamate and ammonia, both of which have neurological effects, psychological and behavioral testing may be especially important.” In other words, a high dietary intake of glutamine may mess with your head.
original abstract †Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
Glutamine is used to supplement intravenous and enteral feeding. Although there have been many human studies of its efficacy, there have been very few studies with safety as a primary goal. This article analyzes the literature on the safety of glutamine and also examines the available information on high intakes of total protein and other amino acids, so that additional indicators of potentially adverse effects can be suggested. Four studies that specifically addressed glutamine safety were identified, from which it was concluded that glutamine is safe in adults and in preterm infants. However, the published studies of safety have not fully taken account of chronic consumption by healthy subjects of all age groups. To help identify potential undetected hazards of glutamine intake, the literature on adverse effects of high dietary intake of protein and other amino acids was examined. High protein is reputed to cause nausea, vomiting and ultimately death in adults, and has been shown to result in neurological damage in preterm infants. Individual amino acids cause a variety of adverse effects, some of them potentially fatal, but neurological effects were the most frequently observed. Because glutamine is metabolized to glutamate and ammonia, both of which have neurological effects, psychological and behavioral testing may be especially important.
This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:
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