Editing Monosodium glutamate (section)

==Safety==
MSG is [[generally recognized as safe]] to eat.<ref name=FDA/><ref>{{cite web|url=https://fivethirtyeight.com/features/how-msg-got-a-bad-rap-flawed-science-and-xenophobia/|title=How MSG Got A Bad Rap: Flawed Science And Xenophobia|first=Anna Maria|last=Barry-Jester|date=8 January 2016}}</ref> A popular belief is that MSG can cause headaches and other feelings of discomfort, but [[Blinded experiment|blinded tests]] have not provided strong evidence of this.<ref name=Ob2016 /> International bodies governing food additives currently consider MSG safe for human consumption as a flavor enhancer.<ref name="Walker00">{{cite journal |vauthors=Walker R, Lupien JR |title=The safety evaluation of monosodium glutamate|journal=Journal of Nutrition|volume=130 |issue=4S Suppl |pages=1049S–52S|date=April 2000 |pmid=10736380 |doi=10.1093/jn/130.4.1049S|doi-access=free}}</ref> Under normal conditions, humans can metabolize relatively large quantities of glutamate, which is naturally produced in the gut in the course of protein hydrolysis. The [[median lethal dose]] (LD<sub>50</sub>) is between 15 and 18 g/kg body weight in rats and mice, respectively, five times the LD<sub>50</sub> of [[salt|table salt]] (3 g/kg in rats). The use of MSG as a food additive and the natural levels of glutamic acid in foods are not of toxic concern in humans.<ref name="Walker00" /> Specifically MSG in the diet does not increase glutamate in the brain or affect brain function.<ref>{{cite journal |last1=Fernstrom |first1=John D. |title=Monosodium Glutamate in the Diet Does Not Raise Brain Glutamate Concentrations or Disrupt Brain Functions |journal=Annals of Nutrition and Metabolism |date=2018 |volume=73 |issue=Suppl. 5 |pages=43–52 |doi=10.1159/000494782|pmid=30508818 |doi-access=free}}</ref>

A 1995 report from the [[Federation of American Societies for Experimental Biology]] (FASEB) for the [[United States Food and Drug Administration]] (FDA) concluded that MSG is safe when "eaten at customary levels" and, although a subgroup of otherwise-healthy individuals develop an MSG symptom complex when exposed to 3 g of MSG in the absence of food, MSG as a cause has not been established because the symptom reports are anecdotal.<ref name="FASEB">{{cite journal|vauthors=Raiten DJ, Talbot JM, Fisher KD |title=Executive Summary from the Report: Analysis of Adverse Reactions to Monosodium Glutamate (MSG) |journal=Journal of Nutrition |volume=125 |issue=6 |pages=2891S–2906S |year=1996 |pmid=7472671 |doi=10.1093/jn/125.11.2891S |s2cid=3945714 }}</ref>

According to the report, no data supports the role of glutamate in [[chronic disease]]. High quality evidence has failed to demonstrate a relationship between the MSG symptom complex and actual MSG consumption. No association has been demonstrated, and the few responses were inconsistent. No symptoms were observed when MSG was used in food.<ref name="freeman" /><ref name="geha">{{cite journal |author=Geha RS |title=Review of alleged reaction to monosodium glutamate and outcome of a multicenter double-blind placebo-controlled study |journal=J. Nutr. |volume=130 |issue=4S Suppl |pages=1058S–62S |date=April 2000 |pmid=10736382 |doi=10.1093/jn/130.4.1058S |url=http://jn.nutrition.org/content/130/4/1058.long |name-list-style=vanc |author2=Beiser A |author2-link=Alexa Beiser |author3=Ren C |display-authors=3 |last4=Patterson |first4=R |last5=Greenberger |first5=PA |last6=Grammer |first6=LC |last7=Ditto |first7=AM |last8=Harris |first8=KE |last9=Shaughnessy |first9=MA |url-status=dead |archive-url=https://web.archive.org/web/20120114164740/http://jn.nutrition.org/content/130/4/1058.long |archive-date=14 January 2012 |doi-access=free}}</ref><ref name="Tarasoff">{{cite journal|author1=Tarasoff L. |author2=Kelly M.F. |title=Monosodium L-glutamate: a double-blind study and review |journal=Food Chem. Toxicol. |volume=31 |issue=12 |pages=1019–35 |year=1993 |pmid=8282275 |doi=10.1016/0278-6915(93)90012-N}}</ref><ref>{{cite journal |author=Walker R |title=The significance of excursions above the ADI. Case study: monosodium glutamate |journal=Regul. Toxicol. Pharmacol. |volume=30 |issue=2 Pt 2 |pages=S119–21 |date=October 1999 |pmid=10597625 |doi=10.1006/rtph.1999.1337}}</ref>

Adequately controlling for experimental bias includes a blinded, [[placebo-controlled]] [[experimental design]] and administration by capsule, because of the unique aftertaste of glutamates.<ref name="Tarasoff" /> In a 1993 study, 71 fasting participants were given 5 g of MSG and then a standard breakfast. One reaction (to the placebo, in a self-identified MSG-sensitive individual) occurred.<ref name="freeman" /> A study in 2000 tested the reaction of 130 subjects with a reported sensitivity to MSG. Multiple trials were performed, with subjects exhibiting at least two symptoms continuing. Two people out of the 130 responded to all four challenges. Because of the low prevalence, the researchers concluded that a response to MSG was not reproducible.<ref>{{cite journal|author1=Williams, A. N. |author2=Woessner, K.M. |title=Monosodium glutamate 'allergy': menace or myth? |journal=Clinical & Experimental Allergy |volume=39 |pages=640–46 |year=2009 |doi=10.1111/j.1365-2222.2009.03221.x|pmid=19389112 |issue=5 |s2cid=20044934}}</ref>

Studies exploring MSG's role in [[obesity]] have yielded mixed results.<ref>{{cite journal|pmid=20370941|year=2010|last1=Shi|first1=Z|last2=Luscombe-Marsh|first2=ND|last3=Wittert|first3=GA|last4=Yuan|first4=B|last5=Dai|first5=Y|last6=Pan|first6=X|last7=Taylor|first7=AW|title=Monosodium glutamate is not associated with obesity or a greater prevalence of weight gain over 5 years: Findings from the Jiangsu Nutrition Study of Chinese adults|volume=104|issue=3|pages=457–63|doi=10.1017/S0007114510000760|journal=The British Journal of Nutrition|doi-access=free}}</ref><ref name=twsNovK5>{{cite news |author=Bakalar, Nicholas |title=Nutrition: MSG Use is Linked to Obesity |newspaper=The New York Times |quote=Consumption of monosodium glutamate, or MSG, the widely used food additive, may increase the likelihood of being overweight, a new study says. |date=25 August 2008 |url=https://www.nytimes.com/2008/08/26/health/nutrition/26nutr.html |access-date=10 November 2010}}</ref>

Although several studies have investigated anecdotal links between MSG and [[asthma]], current evidence does not support a causal association.<ref>
{{cite journal |author=Stevenson, D. D. |title=Monosodium glutamate and asthma |journal=J. Nutr. |volume=130 |pages=1067S–73S |year=2000 |pmid=10736384 |issue=4S Suppl |doi=10.1093/jn/130.4.1067S |doi-access=free}}</ref>

[[Food Standards Australia New Zealand]] (FSANZ) MSG technical report concludes, <blockquote>"There is no convincing evidence that MSG is a significant factor in causing systemic reactions resulting in severe illness or mortality. The studies conducted to date on Chinese restaurant syndrome (CRS) have largely failed to demonstrate a causal association with MSG. Symptoms resembling those of CRS may be provoked in a clinical setting in small numbers of individuals by the administration of large doses of MSG without food. However, such effects are neither persistent nor serious and are likely to be attenuated when MSG is consumed with food. In terms of more serious adverse effects such as the triggering of [[bronchospasm]] in asthmatic individuals, the evidence does not indicate that MSG is a significant trigger factor."<ref name=FSANZreport>{{cite book|title=Monosodium Glutamate, A Safety Assessment, Technical Report Series No. 20 |url=http://www.foodstandards.gov.au/publications/Documents/MSG%20Technical%20Report.doc |website=FoodStandards.gov.au |publisher=[[Food Standards Australia New Zealand]], Health Minister Chair, Peter Dutton MP |date=June 2003 |access-date=17 January 2015 |isbn=978-0642345202 |issn=1448-3017}}</ref><ref name=FSANZsearch>{{cite web|title=Monosodium glutamate search |url=http://www.foodstandards.gov.au/Search/pages/results.aspx?k=Monosodium+glutamate|website=FoodStandards.gov.au |publisher=[[Food Standards Australia New Zealand]], Health Minister Chair, Peter Dutton MP |access-date=13 August 2014}}</ref></blockquote>

The FSANZ MSG report says that although no data is available on average MSG consumption in Australia and New Zealand, "data from the United Kingdom indicates an average intake of 590mg/day, with extreme users (97.5th percentile consumers) consuming 2,330mg/day" (Rhodes et al. 1991).<ref>{{cite journal | last1 = Rhodes | first1 = Joan | last2 = Titherley | first2 = Alison C. | last3 = Norman | first3 = Julie A. | last4 = Wood | first4 = Roger | last5 = Lord | first5 = David W. | date = 1991 | title = A survey of the monosodium glutamate content of foods and an estimation of the dietary intake of monosodium glutamate | url = https://www.tandfonline.com/doi/abs/10.1080/02652039109374021 | journal = Food Additives & Contaminants | volume = 8 | issue = 5 | pages = 663–672 | doi = 10.1080/02652039109374021 | pmc =  | pmid = 1818840 | access-date = 25 May 2023 | name-list-style = vanc }}</ref> In a highly seasoned restaurant meal, intakes as high as 5,000&nbsp;mg or more may be possible (Yang et al. 1997).<ref>{{cite journal | last1 = Yang | first1 = William H. | last2 = Drouin | first2 = Michel A. | last3 = Herbert | first3 = Margaret | last4 = Mao | first4 = Yang | last5 = Karsh | first5 = Jacob | date = 1997 | title = The MSG symptom complex: assessment in a double-blind, placebo-controlled, randomized study | url = https://www.jacionline.org/article/S0091-6749(97)80008-5/pdf | journal = The Journal of Allergy and Clinical Immunology | volume = 99 | issue =  6 Pt 1| pages = 757–762 | doi = 10.1016/s0091-6749(97)80008-5 | pmc =  | pmid = 9215242 | access-date = 25 May 2023 | name-list-style = vanc }}</ref> When very large doses of MSG (>5 g MSG in a [[Bolus (medicine)|bolus]] dose) are ingested, plasma glutamate concentration will significantly increase. However, the concentration typically returns to normal within two hours. In general, foods providing metabolizable [[carbohydrate]]s significantly attenuate peak plasma glutamate levels at doses up to 150mg/kg body weight. Two earlier studies{{snd}}the 1987 Joint [[FAO]]/[[WHO]] Expert Committee on Food Additives (JECFA) and the 1995 [[Federation of American Societies for Experimental Biology]] (FASEB){{snd}}concluded, "there may be a small number of unstable asthmatics who respond to doses of 1.5–2.5 g of MSG in the absence of food". The FASEB evaluation concluded, "sufficient evidence exists to indicate some individuals may experience manifestations of CRS when exposed to a ≥3 g bolus dose of MSG in the absence of food".<ref name=FSANZreport />