Monosodium glutamate avoidance for chronic asthma in adults and children
Editorial Group: Cochrane Airways Group
Published Online: 13 JUN 2012
Assessed as up-to-date: 2 MAY 2012
Copyright © 2014 The Cochrane Collaboration. Published by John Wiley & Sons, Ltd.
How to Cite
Zhou Y, Yang M, Dong BR. Monosodium glutamate avoidance for chronic asthma in adults and children. Cochrane Database of Systematic Reviews 2012, Issue 6. Art. No.: CD004357. DOI: 10.1002/14651858.CD004357.pub4.
- Publication Status: Edited (no change to conclusions)
- Published Online: 13 JUN 2012
Monosodium glutamate (MSG) is the sodium salt of the non-essential amino acid, glutamic acid, and is used as a flavour enhancer. It has been implicated in causing adverse reactions, which have been referred to as "Chinese restaurant syndrome". Over the last two decades there have been a number of studies investigating whether MSG ingestion induces an asthmatic response, and several reviews have been published (ILSI 1991; Stevenson 2000; Woods 2001), but no meta-analysis or Cochrane systematic review has been performed.
The objectives of this review are to: 1) identify randomised controlled trials (RCTs) of MSG ingestion and asthma response in adults and children older than two years of age with asthma; 2) assess the methodological quality of these trials; and 3) determine the effect of MSG ingestion on asthma outcomes.
We searched the Cochrane Airways group's Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), and bibliographies of existing trials. Searches were current up to May 2012.
We included RCTs that investigated the effect of MSG on chronic asthma in adults and children.
Data collection and analysis
Two authors independently extracted, entered and analysed data from included studies. We contacted study authors for additional information.
Only two cross-over studies involving 24 adults met the eligibility criteria; the challenge dosages of MSG were 1 g, 5 g and 25 mg/kg. They reported the number of subjects who had a maximum fall in forced expiratory volume in the first second (FEV
The limited evidence available (n = 24) found no significant difference between MSG or the control challenge for the number of subjects who had a maximum fall in FEV
Plain language summary
Monosodium glutamate (MSG) avoidance for chronic asthma in adults and children
Monosodium glutamate (MSG) is used as a flavour enhancer and has been implicated in "Chinese Restaurant Syndrome", causing tightness, burning or numbness in the face, neck and upper chest (although there is no evidence to prove this syndrome). It has also been proposed that asthmatics may react badly to MSG. In two randomised controlled trials (RCTs), involving 24 adult asthmatics, there was no evidence that MSG worsened asthma when compared to control ingestion. Further RCTs are needed.