Monosodium Glutamate (MSG) - A Food Additive

Abstract

p>Monosodium glutamate (MSG) also known as glutamic acid is a non essential amino acid used as a flavor enhancer worldwide. MSG is found naturally in tomatoes, grapes, cheese, mushrooms and other foods. It is one of the most widely used food additive in commercial foods. Monosodium glutamate is believed to be associated with different health problems viz ., obesity, asthma, metabolic disorders, Chinese restaurant syndrome, neurotoxic effects and detrimental effects on the reproductive organs. Literature showed MSG was associated with adverse side-effects particularly in animals including induction of obesity, diabetes, hepatotoxic, neurotoxic and genotoxic effects. Literature showed that increased consumption of monosodium glutamate may be associated with harmful health effects. Further Intensive research is required to explore monosodium glutamate–related molecular and metabolic mechanisms.</p

Full text

The Indian Journal of Nutrition and Dietetics
ISSN: 0022-3174; eISSN: 2348-621X
www.ijndonline.org
DOI:10.21048/ijnd.2020.57.1.23998
1 1 2
Naveen Kumar, R ., Uday kumar, P . and Hemalatha, R .
(Pathology and Microbiology Division, National Institute of Nutrition,
Indian Council of Medical Research, Hyderabad - 500 007, India)
e-mail: naveen.nin@gmail.com
th
(Received 29 July, 2019)
Monosodium Glutamate (MSG) - A Food Additive
Abstract
Monosodium glutamate (MSG) also known as glutamic acid is a non essential amino
acid used as a flavor enhancer worldwide. MSG is naturally found in tomatoes, grapes,
cheese, mushrooms and other foods. It is one of the most widely used food additive in
commercial foods. Monosodium glutamate is believed to be associated with different health
problems viz., obesity, asthma, metabolic disorders, chinese restaurant syndrome,
neurotoxic effects and detrimental effects on the reproductive organs. Literature showed
MSG was associated with adverse side-effects particularly in animals including induction of
obesity, diabetes, hepatotoxic, neurotoxic and genotoxic effects. However the used dose
and method of administration were not comparable with human MSG intake. Literature also
showed that increased consumption of monosodium glutamate may be associated with
harmful health effects. Further Intensive research is required to explore monosodium
glutamate related molecular and metabolic mechanisms.
Keywords: Monosodium glutamate, flavour enhancer, food additive, chinese restaurant
syndrome
Introduction
Foods have two main functions, i.e.
they provide nutrition and an occasion for
pleasurable social events. Both functions
are fulfilled only if a food is actually
1
consumed . Food additives are substances
added to food to maintain or improve its
safety, fres hness, taste, texture, or
appearance. Their use has reached
alarming proportions and humans are daily
exposed to these chemical substances in
their foods without defining the exact safe
2
li mit . The Jo int FAO/W HO Expe rt
Committee on Food Additives (JECFA) is
the international body responsible for
evaluating the safety of food additives.
Mon o sod i um g luta m ate ( MSG)
(E-621), which is sodium salt of glutamic
acid and known as ajinomoto, is one of the
most widely used food additives in
commercial foods. In Asian countries, MSG
demand was i ncreased b ec au se of
changed dietary pattern s, increased
urbanization, improved living standards and
The Indian Journal of Nutrition and Dietetics, Vol.57 (1), January - March 2020
98

continuous development in food processing
industry. Its application has increased over
time and it is found in many different
ingredients and processed foods available
in every market or grocery store. MSG gives
a special aroma to processed foods which is
known as umami in Japanese language.
3
This taste sensation is also called “Savoury” .
In fact, it is found naturally in many protein
containing foods including Parmesan
cheese, milk, meat, fish and in a number of
different vegetables (tomatoes, potatoes,
mushrooms, etc.) and fruits.
MSG belongs to the larger group of
chemicals that are labelled “glutamate”.
Glutamate is one of the non-essential
amino-acids. Glutamate itself is regarded as
one of the most important components in
proteins. Glutamate is a key component in
enhancing the flavor of foods, when it is in its
free form not when it is bound with other
4
amino acids in proteins . The flavor
enhancing properties of MSG were first
discovered in 1908 by Professor Kikunae
Ikeda, a Japanese Chemist at Tokyo
Imperial University who had been working to
isolate the ingredient that gave a particular
taste in Ko mb u Laminaria japonica
5
(a Japanese seaweed) .
MSG a n d g l u t a m a t e a r e t h e
monosodium salts of the glutamic acid.
However, the totally dissociated form of
L (+)-glutamic acid merely exhibits umami
6
effect .
Glutamic acid is produced outside the
body (for use in food, drug, dietary
su pple men ts, cos meti cs, fer til izer s,
personal care products, etc.). It can cause
brain leisons, neuroendocrine disorders,
learning disabilities, neurodegenerative
diseases and many adverse reactions in
humans and animals. MSG consumed in
large quantities may have effects on cell
growth and then chromosomes may lead to
cancer.
Chemical properties of MSG
The compound of MSG is available as
white, crystalline monohydrate powder. It
dissociates into glutamate and sodium ions
in solution. The MSG compound contains
+
separate sodium cations Na and glutamate
−
anions in zwitter ionic form, OOC-CH
+ −7
(NH )-(CH ) -COO . MSG is insoluble in
3 2 2
common organic solvent like ether and it is
soluble in water. It is highly stable at food
8
processing conditions .
History of MSG
MSG was first isolated from seaweed
in Japan during 1908. Japanese chemist,
Ikeda Kikunae, was the first to isolate this
ingredient in sea kelp that had a distinctive,
almost meat-like taste. It was said to
contribute an 'umami' flavour tasty. By the
mid-20th century, MSG was an inevitable
food additive. In 1909 MSG entered the
L-glutamic acid monosodium
Figure 1
Ionic forms of glutamic acid
The Indian Journal of Nutrition and Dietetics, Vol.57 (1), January - March 2020 99
Monosodium Glutamate (MSG) - A Food Additive

market place as Aji-no-moto. Robert Ho
Man Kwok coined the term 'Chinese
restaurant syndrome'. It refers to a group of
symptoms some people experience after
eating food from a Chinese restaurant.
Kw ok did n't ident ify an y p articula r
component of his meal as causing this
effect, but, despite the scarcity of evidence,
MSG was quickly fingered as the culprit.
Production and manufacturing process of MSG
MSG and glu tami c a cid were
produced by extraction which was a slow
and costly method. It was first introduced in
the United States in the late 1940s. Later on
in 1956, large scale production of MSG and
glutamic acid was successfully achieved.
Since 1957, in the United States, MSG was
pr oduced b y bacter ial f erm entation
involving genetically modified bacteria
which secrete glutamic acid through their
cell walls. In 1960s, MSG had become a
9
household word .
MSG is made from corn starch,
sugarcane, sugar beets and molasses
through fermentation process. The bacteria
Corynebacterium glutamicum, previously
known as Micrococcus glutamicum is
mainly used for fermentation process. The
fermentation process is similar to beer, wine
and vinegar production. Once the glutamate
is produced after fermentation process,
the temperature is set to 33 degrees.
Throughout the process the temperature is
raised and lowered until Monosodium
Glutamate crystals is created. It is dried and
used for the further process.
Toxic effects of monosodium glutamate
Many studies have shown the toxic
effect of monosodium glutamate, however
the doses were not similar to human MSG
intake. High dose of MSG affects central
nervous system, liver, adipose tissue and
reproductive organs.
Glutam a t e a cts a s e x citatory
neurotransmitter which excites the nerve
cells in order to relay its signal. MSG leads
to excessive glutamate in the brain and
enhances the stimulation of nerve cells. The
excessive stimulation of neurotransmitters
causes excitotoxicity, a patholog ical
process by which nerve cells get damaged
10
or killed .
Raw materials
Fermentation
Glutamic acid extraction
Glutamic acid separation
Crystallization
Filtration
Drying
Sieving
Storage
Figure 2
Processing of MSG production
The Indian Journal of Nutrition and Dietetics, Vol.57 (1), January - March 2020
100
Naveen Kumar, R. et al.

Animal studies have shown that
neonatal administration of MSG provides a
model of obesity with impaired glucose
tolerance led to concerns of obesity in
humans using MSG in food. The major link
between MSG and obesity is the effect of
MSG on energy balance by increasing
palatability of food and by disrupting the
hypothalamic signalling cascade of leptin
11,12
action .
The potential link of liver alterations
with adipose tissue metabolism in non-
alcoholic steatohepatitis after dietary MSG
have been also shown at 32 weeks of age
C57BL/6J mice which mothers were fed by
low-dose dietary monosodium glutamate
(0.64 g/l; 97 mg/kg) throughout gestation
13
and were weaned onto the same diet . The
st udies o n MSG an d its l ink w ith
reproductive organs were limited to animal
studies. The administration of MSG (2mg/g)
in Swiss Albino Mice during the perinatal
period lead to increase in the number of
pachytene stage of primary spermatocyte
14
compared to controls . At the same time the
higher dose (4mg/g) of MSG in newborn rats
resulted in decreased weight of pituitary
glands and testes and lowered testosterone
level in 4 month old male rats.
Case studies
Case study 1: Monosodium glutamate:
15
Review on clinical reports
The research on 25 years data
revealed that MSG was associated with
increased hunger, food intake and obesity
Case study 2 : Association of Monosodium
Glutamate Intake With Overweight in
16
Chinese Adults: The INTERMAP Study
MSG intake may be associated with
increased risk of overweight
Case study 3: The Safety Evaluation of
17
Monosodium Glutamate
Central nervous system lesions
produced in several species after parenteral
administration of MSG. Comparative
studies indicated that the neonatal mouse
was most sensitive to neuronal injury; older
animals and other species were less so.
Case study 4: Obesity Induced by Neonatal
Monosodium Glutamate Treatment in
Spontaneously Hypertensive Rats: An
1
Animal Model of Multiple Risk Factors
The induction of hypothalamic obesity
through neonatal MSG treatment leads to
metabolic syndrome X
Case study 5: The Monosodium Glutamate
Symptom Complex: Assessment in a
Do uble -Bl ind , P lac ebo- Con tro lled ,
19
Randomized Study
Hea d a c h e , m u s c le t igh t n e s s ,
numbness/tingling, general weakness, and
flushing occurred more frequently after
MSG than placebo ingestion.
Case study 6: Monosodium Glutamate-
Induced Asthma: Study of the Potential
Risk of 30 Asthmatics and Review of the
20
literature
High dose of >2.5g of MSG caused
intrinsic asthma.
The Indian Journal of Nutrition and Dietetics, Vol.57 (1), January - March 2020 101
Monosodium Glutamate (MSG) - A Food Additive

Safety of MSG with recent evidence of science
There are many studies conducted on
effect of MSG with reference to human
health like overweight, hypertension,
asthma, serum estrogen and progesterone
levels, dylipidemia etc. Based on the review
of literature and evidence based scientific
databases high quality MSG is safe for all
life cycle stage. The researchers who are
working on MSG are advised to use
appropriate scientific methodology and
advised to consider glutamate metabolism
because food glutamate is completely
metabolized by gut cells as energy source
and serve as a substrate for other
21
metabolites in the liver . Majority of the
dietary glutamate is metabolized by the
22
gastrointestinal tract . A recent study
23
conducted by Kasozi et al indicated that
concentration below 5% MSG is safe in food
supplements. Similar kind of study on MSG
showed that MSG in the diet does not
lead to an increase in brain glutamate
concentrations, and thus does not produce
24
functional disruptions in brain . Another
study on review of extrapolation to the
alleged health effects of MSG summarized
that in most of the studies, several
methodological flaws and limited relevance
for dietary intake of MSG risk exposure,
excessive dosing that does not meet with
levels normally consumed in food products
25
was observed .
Indian standards from fssai
Bureau of Indian Standards New
Delhi, India has developed food standards
on “Macaroni, Spaghetti, Vermicelli and Egg
Noodles” during July 1993 with IS
1485/1993 which was reaffirmed during
2005 as second revision.
Essential ingredients are maida or
suji, egg and water. Optional ingredients are
milk powder (whole and skimmed), edible
casein, edible tapioca floor, edible oilseeds
floor, spices, gluten, soya floor, disodium
ph osp hat e, v ege tab le or v ege tab le
products and fruits or fruit products
(preserved, dehydrated or pulp).
Egg noodles
The materials should be in the form of
ribbons, and shall have not less than 5.5%
by mass of egg solids or egg yolk solids.
N o o d l e s s h o u l d b e o f g o o d
characteristic color, flavour and odour and
shall be free from rancidity, mustiness,
bitterness or any other any undesirable
taste or odour. It shall also be free from
impurities, any foreign matter, cracks, flaws,
mould, insect infestation or other spoilage.
The material shall retain its shape and show
no signs of disintegration and shall swell
appreciably when plunged into vigorously
boiling water and boiled for 10 min.
Pasta Products Regulation
Means the product obtained from one
or a combination of ingredients including
The Indian Journal of Nutrition and Dietetics, Vol.57 (1), January - March 2020
102
Naveen Kumar, R. et al.

suji, maida, rice flour, groundnut flour,
tapioca flour, edible soy flour or flour of any
other cereal referred to in sub-regulation 2.4
by kneading the dough and extending it or
by any other process.
It may contain one or more of the
following ingredients either singly or in
combination: Milk powder, fruit and
vegetables and products thereof or their
extracts; edible common salt, nutritive
sweeteners, meat and products thereof; fish
and products thereof; eggs and products
thereof; spices, condiments and herbs
including their extracts; vitamins and
minerals; edible fats and oils; yeast extract,
yeast and product thereof; hydrolysed plant
protein and soy sauce powder.
It may contain food additives specified
in Appendix A of FSSAI appended to these
regulations. It shall be free from dirt, insect's
larvae and impurities or any othe r
extraneous matter. Monosodium glutamate
(E-621) is a flavour enhancer. Every
advertisement for and/or a package of food
containing added Monosodium Glutamate
shall carry the following declaration,
namely:-
“THIS PACKAGE OF (Name of the food contains
added)............
MONOSODIUM GLUTAMATE
NOT RECOMMENDED FOR INFANTS
BELOW - 12 MONTHS”
Regulation 4.2.2: Flavouring Agents and Related
Substances
Use of Monosodium Glutamate
Monosodium Glutamate may be
added to foods as per the provisions
obtained in Appendix C, subject to Good
Manufacturing Practices (GMP) level and
under proper label declaration as provided
in Regulation 4.1.14 (21) of these
Regulations. It shall not be added to any
food for use by infant below twelve months
and in the following foods:-
(Li st o f f oods wher e M o noso dium
Glutamate is not allowed)
(I) Milk and milk products including
buttermilk
(ii) Fe rment ed and r ennet ed milk
products (plain) excluding dairy
based drink
(iii) Pasteurized cream
(iv) Sterilised, UHT, whipping or whipped
and reduced fat creams
(v) Fats and oils, food grains, pulses, oil
seeds and grounded / powdered food
grains
(vi) Butter and concentrated butter
(vii) Fresh fruit
(viii) Surface treated fruit
(ix) Peeled or cut fruit
(x) Fresh vegetables
(xi) Frozen vegetables
(xii) Whole, broken or flaked grains,
including rice
(xiii) Flours of cereals, pulses a nd
starches
(xiv) Pastas and noodles (only dried
products)
The Indian Journal of Nutrition and Dietetics, Vol.57 (1), January - March 2020 103
Monosodium Glutamate (MSG) - A Food Additive

(xv) Fresh meat, poultry and game,
whole pieces or cuts or comminuted
(xvi) Fresh fish and fish products,
including mollusks, crustaceans
and echinoderms
(xvii) Processed fish and fish products,
including mollusks, crustaceans
and echinoderms
(xviii) Fresh eggs, liquid egg products,
frozen egg products
(xix) Whi te a nd semi - whi t e s u gar
(sucrose and sacharose, fructose,
glucose (dextrose), xylose, sugar
solutions and syrups, also (partially)
inverted sugars, including molasses,
treacle and sugar toppings
(xx) Other sugars and syrups (e.g. brown
sugar and maple syrup)
(xxi) Honey
(xxii) Salt
(xxiii) Herbs, spices and condiments,
seasoning (including salt substitutes)
except seasoning for noodles and
pastas, meat tenderizers, onion salt,
garlic salt, oriental seasoning mix,
top pin g to s pri n kle on rice ,
fermented soyabean paste, yeast
(xxiv) Infant food and infant milk substitute
including infant formulae and follow-
on formulate
(xxv) Foods for young children (weaning
foods)
(xxvi) Natural m i n erals w a t e r and
packaged drinking water
(xxvii) Concentrates (liquid and solid) for
fruit juices
(xxviii) Canned or bottled (pasteurized)
fruit nectar
(xxix) Coffee and coffee substitutes, tea,
herbal infusions, and other cereal
beverages excluding cocoa
(xxx) Wines
(xxxi) Margarine
(xxxii) Fat spread
(xxxiii) Fruits and vegetables products
except those where monosodium
glutamate is permitted under these
regulations
(xxxiv) Carbonated water baking powder
(xxxv) Baking powder
(xxxvi) Arrowroot
(xXxxvii) Sago
(xxxviii) Plantation sugar, jaggery and bura
(xxxix) Ice-Candies
(xl) Ice cream and frozen desserts
(xli) Cocoa butter
(xlii) Saccharine
(xliii) Malted milk food and milk based
foods
(xliv) Bread
(xlv) Vinegar
(xlvi) Su gar conf ecti one r y, t off e e,
lozenges
(xlvii) Chocolate
(xlviii) Pan masala
(Xlix) Alcoholic beverages
Permissible maximum level in fish
products: 500 mg/kg
The Indian Journal of Nutrition and Dietetics, Vol.57 (1), January - March 2020
104
Naveen Kumar, R. et al.

Food standards in Australia and Newzealand on
MSG (Fsanz)
The technical report of FSANZ
concludes that there is no evidence that
MSG is a significant factor in causing
systemic reactions resulting in illness and
mortality. However the standards of
Australia and Newzealand specify that Food
Standards Code requires MSG to be
labelled in packaged foods. The label must
have the food-additive class name (e.g.
"flavour enhancer"), followed by the name of
the additive ("MSG") or its International
Numbering System (INS) number, 621
(FSAN).
CODEX (CCFAC)/JECFA standards on MSG
JECFA had set an ADI "not specified"
for MSG and had considered the question of
single high intakes in relation to intolerance
reactions. In addition JECFA no longer
made reference to the ADI not applying to
infants under 12 weeks of age. However, it
still maintained its general recommendation
regarding the use of food additives in foods
for infants. JECFA report will state that it
believes that the use of these substances
should be used in infant foods with caution.
Conclusion
In India the use of MSG is not
recommended and cannot be added to
foods meant for infants below 12 months, it
can be added as flavour enhancer in other
foods, but label should have advisory
indicating that is not recommended for
infants. There are no limits prescribed for its
use, as it is self limiting and used as per
GMP. The toxic effects of MSG on central
nervous system, liver, adipose tissue,
reproductive organs were shown in many
studies; however the used dose and method
of administration were not comparable with
human MSG intake. The conclusion is
intense research is required to explore
monosodium glutamate related molecular
and metabolic mechanisms.
Requirements for Macaroni, Spaghetti, Vermicelli and Egg Noodles as per FSSAI
1. Moisture, per cent by mass Max. 11
2. Total ash (on dry basis), per cent by mass Max. 0.7
3. Acid insoluble ash (on dry basis), per cent by mass Max. 0.05
4. Total protein (Nx5.7) (on dry basis), per cent by mass Min. 10
5. Cooking test: Total solids in gruel, (on dry basis), per cent by mass Max. 8
6. Free acidity (mL of 1 N NaOH solution per 100 g of product) Max. 4
Based on FSSAI decision, MSG may be added as per the provisions subjected to GMP.
The Indian Journal of Nutrition and Dietetics, Vol.57 (1), January - March 2020 105
Monosodium Glutamate (MSG) - A Food Additive

REFERENCES
1. Bera, T.K., Kar, S.K., Yadav, P.K., Mukherjee, P., Yadav, S. and Joshi, B. Effects of sodium
glutamate on human health: A systematic review. World J. Pharma. Sci., 2017, 5, 139-144.
2. Zia, M.S., Hanif, K.R. and Khalil, M. Effect of monosodium glutamate on the serum estrogen and
progesterone levels in female rat and prevention of this effect with diltiazem. J. Ayub. Med. Coll.
Abbollabad., 2014, 26, 18 -20.
3. Xiong, J.S., Branigan, D. and Lim. Peciphering the MSG Controversy. Int. J. Clin. Exp. Med.,
2009, 2, 329-336.
4. Singh, 2005. Fact or Fiction, The MSG Controversy. 2005 Retrieved from
http://nrs.harvard.edu.
5. Anonymous. History of Invention and use of MSG. n.d. 2016 Retrieved from
http://www.truthinlabelling.org.
6. Wijayasekara, K. and Wanaspal, J. Uses, effects and properties of monosodium glutamate
(MSG) on food and nutrition. Int. J. Fd. Sci. Nutr., 2017, 2, 132-143.
7. Win. C., ed. Principles of Biochemistry. Boston, MA: Brown Pub Co. 1995.
8. Yamaguchi, Shizuko, Tokyo University of Agriculture, Japan; Ninomiya, Kumiko, Technical
Committee, Umami Manufacturers Association of Japan. What is umami?. Fd. Rev. Int., 1998,
14, 123-138.
9. Kazmi, Z., Fathma, I., Perveen, S. and Malik, S.S. Monosodium glutamate: review on clinical
reports. Int. J. Fd. Proper., 2012, 1807-1815.
10. Husarova, V. and Ostatnikova, D. Monosodium glutamate toxic effects and their implications for
human intake: A review. JMED Res., 2013, 1-13.
11. He, K., Du, S., Xun, P., Sharma, S., Wang, H., Zhai, F. and Popkin, B. Consumption of
monosodium glutamate in relation to incidence of overweight in Chinese adults: China Health
and Nutrition Survey (CHNS), The Am. J. Clin. Nutr., 2011, 93, 1328-1336.
12. Hermanussen, M. and Tresguerres, J.A.F. Does high glutamate intake cause obesity?,
J. Pediat. Endocrinol.Metabol., 2003, 16, 965-968.
13. Collison, K.S., Makhoul, N.J., Inglis, A., Al-Johi, M., Zaidi, M.Z., Maqbool, Z., Saleh, S.M.,
Bakheet, R., Mondreal, R., Al-Rabiah, R., Shoukri, M., Milgram, N. W. and Al-Mohanna, F.A.
Dietary trans-fat combined with monosodium glutamate induces dyslipidemia and impairs
spatial memory. Physiol. Behavior., 2010, 99, 334-342.
14. Das, R.S. and Ghosh, S.K. Long term effects of monosodium glutamate on spermatogenesis
following neonatal exposure in albino mice- A histological study. Nepal Med. Coll. J., 2010, 12,
149-153.
15. Kazmi, Z., Fatima, I., Perveen, S. and Malik, S.S. Monosodium glutamate: review on clinical
reports. Int. J. Fd. Proper., 2017, 20, 1807-1815. Retrieved from
https://www.fssai.gov.in/home/fss-legislation/fss-regulations.html.
16. He, K., Zaho, L., Daviglus, M.L., Dyer, A.R., Horn, L.V., Garside, D., Zhu, L., Guo, D., Wu, Y.,
Zhou, B. and Stamler, J. Association of monosodium glutamate intake with overweight in
chinese adults: the INTERMAP study. Obesity, 2008, 16, 1875-1880.
The Indian Journal of Nutrition and Dietetics, Vol.57 (1), January - March 2020
106
Naveen Kumar, R. et al.

17. Walker, R. and Lupien, J.R. The safety evaluation of monosodium glutamate. The J. Nutr., 2000,
130, 1049-1052.
18. Iwase, M., Yamamoto, M., Lino, K., Ichikawa, K., Shinohara, N., Yoshinari, M. and Fujishima, M.
Obesity induced by neonatal monosodium glutamate treatment in spontaneously hypertensive
rats: an animal model of multiple risk factors. Hyperten. Res., 1998, 21, 1-6.
19. Yang, W.H., Drouin, M.A., Herbert, M., Mao, Y. and Karsh, J. The monosodium glutamate
symptom complex: assessment in a double-blind, placebo-controlled, randomized study. J.
Aller. Clini. Immunol., 1997, 99, 757-762.
20. Vautrin, M.D.A. Monosodium glutamate-induced asthma: study of the potential risk of 30
asthmatics and review of the literature. Allergie et Immunologie., 1987, 19, 29-35.
21. Henry-Unaeze, H. N. Update on food safety of monosodium I-glutamate (MSG). Pathophysiol.,
2017, 24, 243-249.
22. Wijayasekara, K. and Wansapala J. Uses, effects and properties of monosodium glutamate
(MSG) on food and nutrition. Int. J. Fd. Sci. Nut., 2017, 2, 132-143.
23. Kasozi, K.I., Namubiru, S, Kiconco, O., Kinyi, H.W., Ssempijja, F., Ezeonwumelu J.O.C.,
Ninsiima, H.I. and Okpanachi, A.O. Low concentrations of monosodium glutamate (MSG) are
safe in male Drosophila melanogaster. BMC Res. Notes, 2018, 11, 670.
24. Fernstrom, J.D. monosodium glutamate in the diet does not raise brain glutamate
concentrations or disrupt brain functions. Ann. Nutr. Metabol., 2018, 73, 43-52.
25. Zanfirescu, A., Ungurianu, A., Tsatsakis, A.M., Nitulescu, G.M., Kouretas, D., eskoukis, A.,
Tsoukalas, D., Engin, A.B., Aschner, M. and Margina, D. A review of the alleged health hazards
of monosodium glutamate. Compreh. Rev. Fd. Sci. Fd. Safety, 2019, 18, 1111-1134.
The Indian Journal of Nutrition and Dietetics, Vol.57 (1), January - March 2020 107
Monosodium Glutamate (MSG) - A Food Additive