European Journal of Clinical Nutrition (2005), 1–7& 2005 Nature Publishing Group All rights reserved 0954-3007/05 $30.00
Obesity, voracity, and short stature: the impact ofglutamate on the regulation of appetite
M Hermanussen1, AP Garcı´a2, M Sunder3, M Voigt4, V Salazar2 and JAF Tresguerres2
1Aschauhof, Altenhof, Germany; 2Department of Physiology Medical School, Universidad Complutense, Madrid, Spain;3Volkswirtschaftliches Institute, Ludwig-Maximilian University, Munich, Germany and 4Department Neonatology and PaediatricIntensive Care, Ernst-Moritz-Arndt-University, Zentrum fu¨r Kinder- und Jugendmedizin, Greifswald, Germany
Background: World-wide obesity has risen to alarming levels. We present experimental support for a new and very challenginghypothesis linking obesity, voracity, and growth hormone (GH) deficiency, to the consumption of elevated amounts of theamino-acid glutamate (GLU). Supraphysiological doses of GLU are toxic for neuronal cells. Methods: Human data were obtained from 807 592 German conscripts born between 1974 and 1978, and from 1 432 368women of the German birth statistics (deutsche Perinatalerhebung) 1995–1997. The effects of orally administered monosodiumglutamate (MSG) were investigated in 30 pregnant Wistar rats and their offspring. Pregnant animals either received no extraMSG, or 2.5 g MSG, or 5 g MSG per day, up to the end of the weaning period. In all, 2.5 g, respectively 5 g, MSG accounted forsome 10%, respectively 20%, of dry weight of the average daily food ration. After weaning, MSG feeding was continued in theoffspring. Findings: Morbid obesity associates with short stature. Average stature of conscripts progressively declines when body massindex increases above 38 kg/m2. Also morbidly obese young women are shorter than average though to a lesser extent thanconscripts. Oral administration of MSG to pregnant rats affects birth weight of the offspring. Maternal feeding with 5 g MSG perday results in severe birth weight reduction (Po0.01). Weight increments remain subnormal when MSG feeding to the mothersis maintained during weaning (Po0.01). GH serum levels are affected in animals that received MSG during prenatal life viamaternal feeding. Animals that are kept on high MSG diet (5 g MSG per day) continue to show serum GH levels that are as lowor even lower than those of MSG injected animals (Po0.05), both at day 30 and at day 90 of life. Animals that were kept onmedium MSG diet (2.5 g MSG per day) showed low serum GH levels at day 30 of life (Po0.01), but seemed to partially recoverbefore day 90. Almost identical results were observed in IGF-1 serum levels. Oral MSG resulted in dose dependent voracity. Theanimals fed 5 g MSG per day increased water uptake by threefold (Po0.01), and food uptake by almost two-fold (Po0.01). Theinfluence of MSG is in general more marked in males than in females. Interpretation: GLU is a widely used nutritional substance that potentially exhibits significant neuronal toxicity. Voracity, andimpaired GH secretion are the two major characteristics of parenterally administered GLU-induced neuronal damage. GLUmaintains its toxicity in animals even when administered orally. Males appear to be more sensitive than females. The presentstudy for the first time demonstrates, that a widely used nutritional monosubstance – the flavouring agent MSG – atconcentrations that only slightly surpass those found in everyday human food, exhibits significant potential for damaging thehypothalamic regulation of appetite, and thereby determines the propensity of world-wide obesity. We suggest to reconsiderthe recommended daily allowances of amino acids and nutritional protein, and to abstain from the popular protein-rich diets,and particularly from adding the flavouring agents MSG. European Journal of Clinical Nutrition advance online publication, 31 August 2005; doi:10.1038/sj.ejcn.1602263
Keywords: obesity; voracity; short stature; glutamate; arcuate nucleus
Correspondence: Professor M Hermanussen, Aschauhof 3, 24340 Altenhof,Germany. E-mail: hermanussen.aschauhof@t-online.de
World-wide obesity has risen to alarming levels (McLellan,
Guarantors: M Hermanussen and JAF Tresguerres.
2002). The average weight of German conscripts now
Contributors: MS is responsible for conscript data; MV for women’s data; APG,
increases by almost 400 g/year. Similar data were obtained
VS and JAFT for animal data; and MH for idea, coordination and writing. Received 20 December 2004; revised 31 May 2005; accepted 7 July 2005
in Austria, Norway, and the UK. Obesity is not a separate
problem of only the obese people but appears to be a
levels and activation of GLU-receptors after neonatal s.c.
characteristic feature of modern populations as a whole
administration of MSG at doses of 4 mg/g body weight and
an increase in glial cell reactivity and important changes in
Much effort has been spent to understand the patho-
NMDA-R molecular composition, with signs of neuronal
physiology of obesity. Apart from the rare monogenic causes
damage. Kaufhold et al. (2002) were able to prevent the
for severe disturbances of the eating regulation – genetic
adverse effects of neonatal MSG treatment by concurrent
alterations of the ob gene (leptin) (Zhang et al., 1996; Strobel
administration of a selective and highly potent noncompe-
et al., 1998), the leptin receptor (Clement et al., 1998), a
mutation of the melanocortin 4 receptor (MC4R) gene
Administering GLU to newborn rodents not only destroys
(Farooqi et al., 2000), and mutations in the pro-opiomelano-
arcuate nucleus neurones, it also damages other hypotha-
cortin (POMC) gene (Krude et al., 1998) – obesity appears to
lamic areas. Bloch et al. (1984) showed that MSG treatment
show a multifactorial aetiopathogenesis. Disadvantageous
results in the complete loss of growth hormone releasing
dietary habits, such as overconsumption of fat-rich diets,
factor (GRF)-immunoreactive cell bodies within this nucleus
excessive use of modern media, in particular television
and provokes a selective disappearance of GRF-immuno-
viewing (Robinson, 2001), a sedentary lifestyle (Votruba
reactive fibres in the median eminence of rats. This
et al., 2000), and many other exogenous factors, have been
technique has routinely been practised to produce function-
made responsible for the development of obesity already in
ally hypopituitary animals (Lima et al., 1993) for studies of
early childhood. And recently, a new and very challenging
short-term growth (Hermanussen et al., 1996).
hypothesis has been added linking obesity, voracity, and
That is, GLU-induced neuronal damage results in voracity
growth hormone (GH) deficiency to the consumption of
and subsequent excessive weight gain, and impaired GH
elevated amounts of the amino-acid glutamate (GLU)
secretion, the two major characteristics of human obesity.
(Hermanussen and Tresguerres, 2003a, b). Supraphysiological
The present study was undertaken to further investigate
doses of GLU are toxic for neuronal cells.
the links between obesity, voracity, and GH deficiency. We
The arcuate nucleus is the major site of GLU-induced
present novel human data supporting evidence that morbid
neuronal damage in the hypothalamus. It is situated close to
obesity not only associates with GH secretory dysfunction,
the bottom of the third ventricle, and is a potent site of
but also with short stature, and animal data supporting
leptin action. Leptin is produced in the adipose tissue,
evidence that GLU toxicity is not limited to parenteral
crosses the blood-brain barrier by active transport systems,
administration of this amino acid, but that oral administra-
and stimulates a specific signalling cascade (Jequier, 2002): it
tion of GLU also causes voracity and GH deficiency. The
downregulates the orexigenic neuropeptides NPY, agouti
similarity between clinical findings in human obesity, and
gene-related protein, melanin-concentrating hormone, and
effects of oral administration of MSG in laboratory animals
orexins, and upregulates POMC and cocaine- and ampheta-
strongly support the view that supraphysiological oral loads
mine-regulated transcript (CART) mRNA (Elmquist, 2001).
of the amino-acid GLU play a key role in human obesity.
POMC and its post-translational product, alpha-MSH, stimu-late melanocortin receptors (MC3R, MC4R), and therebydownregulate appetite. Arcuate nucleus damage disrupts the
signalling cascade of leptin action, thereby impairs theregulation of appetite, and causes voracity (Fan et al., 1997;
Body height and body mass index (BMI) were obtained from
GLU toxicity is mediated either by inhibiting cystine
807 592 German conscripts born between 1974 and 1978,
uptake (Murphy et al., 1990) or receptor-mediated. The
aged 19–20 years. BMI ranged between 14 and 48 kg/m2. In
N-methyl-D-aspartate receptor (NMDA-R) is fully functional
all, 4.7% of the young men were obese with BMI X30 kg/m2,
in the rat early in embryogenesis. Xue et al. (1997) found
and some 20% overweight with BMI X25 kg/m2. The data
that GLU- and aspartate-immunoreactive neurones were
were given to us by courtesy of the Institut fu
completely absent in the monosodium glutamate (MSG)-
zinalstatistik und Berichtswesen, Remagen, Germany. All
lesioned arcuate nucleus as well as the ventromedial nucleus
conscripts had either completed high school (A–level,
lateral to the arcuate nucleus, in mice treated neonatally
German: Gymnasium), secondary school (O-level, German:
with MSG. Similarly, NMDA-R1-immunoreactive neurones
were mostly absent in the MSG-lesioned arcuate nucleus but
Hauptschule). We excluded persons who were chronically
remained intact in the ventromedial nucleus. There was also
ill, or lived under the care of a guardian, and conscripts who
a substantial loss of NMDA-R2 immunoreactivity within the
did not complete school education (less than 10%). This was
arcuate nucleus. Beas-Zarate et al. (2001) measured changes
performed on purpose in order to exclude mentally handi-
in gene expression of the NMDA-R subunits: NMDA-R1,
capped subjects suffering from Down’s Syndrome, Prader-
NMDA-R 2A, and NMDA-R 2B in the cerebral cortex,
Willi-Syndrome, and other syndromes with short stature and
striatum and hippocampus in the brains of rats treated
obesity. We assumed that very obese young men had also
neonatally with MSG. The authors showed increases in GLU
been obese during the final period of adolescent growth.
Obesity, voracity, and short statureM Hermanussen et al
Maternal data on body height and weight at the beginning
registered daily. Offspring was killed half at day 30 and the
of pregnancy from 1 432 368 women were obtained from the
German birth statistics (deutsche Perinatalerhebung) 1995–1997 (Voigt et al., 2001). BMI ranged between 12 and 59 kg/m2. A 10.4% of the young women were obese with BMI X30 kg/
m2, and some 35% overweight with BMI X25 kg/m2. We
Half of the animals were killed by decapitation at day 30 and
rejected adolescent mothers (o18 years of age), in order to
the other half at the end of the observation period at day 90.
exclude those who had not yet reached final height, and
Anterior pituitaries were removed, and trunk blood was
restricted the sample to persons below the age of 30 years.
collected. Serum samples and anterior pituitaries after being
We assumed that very obese young women had also been
weighted were kept at À801C, for hormonal determinations
obese during the final period of adolescent growth. We are
by specific radioimmunoassays (RIA). Pituitary homogenates
aware that data obtained from birth statistics are not
were obtained by manual glass homogenisers, and processed
representative for women in general. Pregnancy provides
in saline after thawing in the moment of the measurement.
evidence for unimpaired hypothalamic-pituitary-gonadalfunction. However, large samples of unselected youngwomen are not available in Germany.
Plasma GH levels and pituitary GH content were determined
by RIA as previously described (Lima et al., 1993). Pituitary
The effects of oral administration of GLU were investigated
homogenates were diluted 1:5000 for determination. Reagents
in 32 pregnant rats and their offspring up to day 90 of life, in
were kindly provided by the National Institute of Diabetes,
the animal facilities of the Department of Physiology,
Digestive, and Kidney Diseases (NIDDK). The standard used
Medical School, Universidad Complutense, Madrid, Spain.
was rat GH RP2. The sensitivity of the curve was 2 ng/ml and
The study was conducted in accordance with the principles
the Intraassay coefficient of variation was 5.7%.
and procedures outlined in the NIH Guide for the Care and
Plasma IGF I concentrations were measured using a
Use of Laboratory Animals. Pregnant Wistar rats were kept
commercially available rat RIA kit (DSL-2900, Diagnostic
under controlled conditions of light (12 h light/12 h
Systems Laboratories, Inc.). The sensitivity of the assay was
darkness) and temperature (2172C1), and were fed with
20 ng/ml, and the intraassay coefficients of variation for
tap water and rat chow (Panlab, Barcelona, Spain) ad libitum.
mean serum concentrations of 323, 772, and 1604 ng/ml
At day 14 of pregnancy, the animals were divided into four
were 5.9, 6.1, and 3.8%, respectively.
groups (n ¼ 8), and either received no extra MSG (control,
Leptin levels were determined by RIA using a commercial kit
group 1), or 2.5 g MSG (group 2) or 5 g MSG per day (group
(RL-83 K, LINCO RESEARCH), with a sensitivity of 0.5 ng/ml,
3), up to the end of the weaning period. 2.5 g, respectively,
and intra-assay coefficients of variation of 2.4% (1.6 ng/ml),
5 g MSG accounted for some 10%, respectively, 20% of dry
4.1% (3.3 ng/ml), 2% (6.8 ng/ml), and 4.6% (11.6 ng/ml).
weight of the average daily food ration. After weaning andgender separation, MSG feeding was continued in theoffspring at the same concentrations.
Group 4 was not given MSG with the chow, and thus
Values are expressed as mean7s.e.m. In some cases data were
exactly resembled the control group 1, but their offspring
subject to log transformation since variances showed a log-
was injected with MSG 4 mg/g body weight s.c., on alternate
normal distribution. To determine differences in final weight
days from day 1 to day 10 of life. Injecting MSG 4 mg/g body
or hormonal levels a two-way ANOVA test was performed.
weight s.c. at neonatal age, is known to deplete the arcuate
Differences among groups were subjected to a post hoc
nucleus of GHRH neurons (Bloch et al., 1984) thus leading to
comparison by using Tukey HSD for unequal N-test. Statistics
GH deficiency. Also, our group had previous experience with
were executed using Statistica program. The significance
this model when investigating the growth process in GH
deficient animals (Hermanussen et al., 1996). Four mg/gcorrespond to 1 g in a 250 g rat, That is, the s.c. dose was kepta little lower than the dose range of the orally treated groups.
The bioavailability of s.c. administered MSG might behigher, and also different in terms of GLU/glutamine
conversion. The offspring of group 4 was important in order
Morbid obesity associates with short stature. Regardless of
to compare the effects of s.c. vs orally administered MSG.
school education, average stature of conscripts progressively
Owing to the existence of two gender groups a total of
declines when BMI increases above 38 kg/m2. The same
eight experimental groups were obtained with n ¼ 6–9 for
applies for fertile women. Morbidly, obese young women are
each group of females and males. All litter was weighed at
shorter than average (Figure 1) though to a lesser extent than
weekly intervals, and the amount of food consumed was
with 2.5 g MSG per day (group 2) results in no birth weight
Oral administration of MSG to pregnant Wistar rats affects
modification as compared to controls, whereas maternal
birth weight of the offspring (Figure 2a). Maternal feeding
feeding with 5 g MSG per day (group 3) results in severe birthweight reduction (Po0.01). Weight increments remainsubnormal when MSG feeding to the mothers is maintainedduring weaning (Figure 2b) (Po0.01).
Figure 3a, b shows GH plasma levels of the offspring.
As expected, GH plasma levels were low in animals that
were neonatally injected with MSG, both at day 30 and atday 90 of life (Po0.05). However, GH serum levels were also
affected in animals that had received MSG during prenatal
life via maternal feeding. Figure 3b illustrates that animalskept on high MSG diet (5 g MSG per day) show serum GH
levels that are as low or even lower than those of MSG
injected animals (Po0.05), both at day 30 and at day 90 of
life. The influence of MSG is in general more marked inmales than in females.
Animals that were kept on medium MSG diet (2.5 g MSG
per day) showed low-serum GH levels at day 30 of life
(Po0.01), but seemed to partially recover before day 90.
Almost identical results were observed in IGF-1 serum levels(Figure 4a, b).
Average body height of 807 592 German conscripts
born between 1974 and 1978, aged 19 years, and 1 432 368young German women at the beginning of pregnancy (deutschePerinatalerhebung) 1995–1997 (Voigt et al., 2001), vs BMI. Plasma GH Log (ng/ml) Weigth (g) FEMALES AND MALES FEMALES AND MALES Plasma GH Log (ng/ml) Weigth (g) 15 FEMALES AND MALES
Mean (7 s.e.m.) plasma concentration of GH at 30 days
Mean (7 s.e.m.) birth weight (a) and weaning body
(a), and at 90 days (b) of life in normal rats (control), neonatally
weight (b) in normal rats (control), neonatally MSG-treated rats
MSG-treated rats (injection) and 2.5 g (2.5 g MSG) and 5 g (5 g
(injection) and 2.5 g (2.5 g MSG) and 5 g (5 g MSG) MSG oral
MSG) MSG oral administered rats (n ¼ 12–18 (a), n ¼ 6–9 (b)). Each
administered rats (n ¼ 12–18). Each group includes male and female
group includes male and female data since statistical analysis showed
data since statistical analysis showed no gender differences.
no gender differences. **Po0.01 vs CONTROL group and *Po0.05
**Po0.01 vs other groups (a), **Po0.01 vs CONTROL þ INJECTION
vs CONTROL group (a), *Po0.05 vs CONTROL þ 2.5 g MSG and
groups and #Po0.05 vs 2.5 g MSG group (b).
##Po0.01 vs the corresponding FEMALE group (b).
Obesity, voracity, and short statureM Hermanussen et al
PlasmaI GF-1 Log (ng/ml) Water uptake (ml) FEMALES AND MALES PlasmaI GF-1 Log (ng/ml) Food uptake (g) FEMALES AND MALES
Mean (7 s.e.m.) water (a) and food (b) uptake at 90 days
Mean (7 s.e.m.) IGF-1 plasma concentration at 30 days
of life in normal rats (control), neonatally MSG-treated rats
(a) and at 90 days (b) of life in normal rats (control), neonatally
(injection) and 2.5 g (2.5 g MSG) and 5 g (5 g MSG) MSG oral
MSG-treated rats (injection) and 2.5 g (2.5 g MSG) and 5 g (5 g
administered rats (n ¼ 6–9). **Po0.05 vs CONTROL þ INJECTION
MSG) MSG oral administered rats (n ¼ 12–18 (a), n ¼ 6–9 (b)). Each
groups; wPo0.05 vs INJECTION group; zzPo0.01 vs 2.5 g MSG
group includes male and female data since statistical analysis showed
group and ##Po0.01 vs the corresponding FEMALE group (a),
no gender differences. **Po0.01 vs CONTROL group (a), **Po0.01
**Po0.01 vs CONTROL þ INJECTION group (b).
vs CONTROL þ 2.5 g MSG and ##Po0.01 vs the correspondingFEMALE group (b).
Figure 5a, b shows the influence of MSG on appetite.
Whereas – in contrast to previous findings (Fan et al., 1997) –
Glutamic acid (GLU) is the most common amino acid in
MSG-injected animals of this investigation did not show
animal protein, and accounts for some 16% of meat protein,
significantly increased appetite compared to controls, the
and some 20% of milk protein weight. That is, infants who
animals kept on medium MSG diet (2.5 g MSG per day), and
daily consume up to 5 g/kg body weight of protein (Koletzko,
particularly those kept on high MSG diet (5 g MSG per day)
2002), consume as much as 1 g/kg body weight of GLU. GLU
demonstrated marked voracity. The animals fed 5 g MSG per
is also the physiological ligand of the taste receptor umami,
day increased water uptake by threefold (Po0.01), and food
the dominant taste of food containing L-GLU, like chicken
uptake by almost two-fold (Po0.01). Voracity seems to be MSG-
broth, meat extracts, ageing cheese. Umami is responsible
dose-dependent and the increase was identical in both genders.
for the immediate sensory effect of MSG on the palatability
Leptin values were significantly increased in animals that
of food. MSG is used as flavouring agent.
were neonatally injected with MSG, both at day 30 and at
However, it has long been known that MSG can also
day 90 of life (Po0.05), we found reduced leptin levels in the
intoxicate arcuate nucleus neurones. In 1969, Olney and
Sharpe reported on brain lesions, obesity, and other
Rats orally treated with MSG are smaller and have lower
disturbances in mice (Olney, 1969), and in an infant rhesus
body weight, than control animals. The gravity index
monkey (Olney and Sharpe, 1969) treated with MSG. In
(specific weight, measured in air and water) that provides a
1976, Holzwarth-McBride et al. (1976) investigated the
relative information about the fat content of animal
effect of the MSG induced lesion of the arcuate nucleus by
carcasses, however, indicated that MSG fed animals con-
measuring catecholamine content in this nucleus and the
tained significantly more body fat both at day 30 and at day
median eminence of the mouse hypothalamus. The two
major characteristics of MSG-induced arcuate nucleus
damage hitherto described, are voracity, and impaired GH
those found in everyday human food, exhibits significant
secretion. However, all of these studies focussed on parent-
potential for damaging the hypothalamic regulation of
erally administered MSG. We demonstrated that MSG
appetite. Although the experimental part of this study was
maintains its toxicity even when administered orally.
performed in rodents, and though it remains to be
The influence of MSG is in general more marked in males
elucidated whether rodents are more sensitive to MSG than
than in females. Since MSG has excitotoxic activities and
humans, uneasiness remains when considering that world-
implies oxidative stress, the gender difference may be
wide MSG production has increased from 200 000 (1969), to
explained by to the antioxidant activity of estrogens (Ruiz-
270 000 (1979), to 800 000 tons/year in 2001 (Schmid, 2002)
Larrea et al., 1997; Cuzzocrea et al., 2001). Estrogens have a
(Schmid, 2002, personal communication). First, clinical
very important neuroprotective activity (Azcoitia et al., 1999).
evidence in the treatment of very obese subjects further
The present investigation was performed in animals not
stresses the importance of GLU in the regulation of appetite:
older than 90 days. Although at this age, the animals are still
Blocking GLU action by antagonising GLU-gated Ca2 þ ion
too young to exhibit obvious signs of obesity, MSG fed
channels with memantine normalises binge-eating disorders
animals contain more body fat than controls, and show
within a few hours (Hermanussen and Tresguerres, 2005).
impaired glucose tolerance and insulin resistance (Hirata
Other questions remain: is obesity the disease that we are
et al., 1997). Macho et al. (2000) found a shift in glucose
interested in? Obesity results from a nutritional imbalance.
metabolism towards lipid synthesis in fat tissue, in 3-month-
That is, in view of the present findings, we rather have to
old rats treated with MSG during the postnatal period, and
consider if not voracity is the disease that needs to be
demonstrated an attenuation of insulin effect on glucose
addressed in the first place. It has been shown that obesity
transport due to a lower insulin binding and lower content
associates with GH secretory dysfunction. A 24 h integrated
of GLUT4 protein. They concluded that early postnatal
concentrations of GH were lower in young, obese subjects than
administration of MSG exerts an important effect on glucose
in young subjects who were lean (Meistas et al., 1982). Veldhuis
metabolism and insulin action in adipocytes of adult
et al. (1991) examined the mechanisms underlying the reduced
animals, indicating that apart from excitotoxic effects in
circulating GH concentrations in obese subjects. Obese men
the central nervous system, MSG treatment appears to also
had fewer GH secretory bursts, and both GH secretion rate and
GH burst frequency were negatively correlated with the degree
The present findings are alarming, and throw doubts upon
of obesity (Veldhuis et al., 1991). However, since obesity results
the unscrupulousness of current use of the flavouring agent
from a nutritional imbalance, that is, obesity results from
MSG. L-Glutamic acid was evaluated by the Joint FAO/WHO
voracity – we are now concerned that both the damage in the
Expert Committee on Food Additives (JECFA) in 1988. The
regulation of appetite, and the impaired GH secretion, result
JECFA allocated an ‘acceptable daily intake not specified’ to
from world-wide supraphysiological GLU consumption. The
glutamic acid and its salts with no additional risk to infants.
fact that large BMI associates with short stature, indicates
The Scientific Committee for Food (SCF) of the European
towards the possibility that both excessive appetite and growth
Commission reached a similar evaluation in 1991. The
conclusions of a subsequent review by the Federation of
If this be the case, many more questions arise: Do other
American Societies for Experimental Biology (FASEB) and the
amino acids metabolise into GLU, do other amino acids lead
Federal Drug Administration concurred with the safety
to similar toxic effects when fed at supraphysiological doses?
evaluation of JECFA and the SCF (Walker and Lupien,
Is GLU the only ligand that causes NMDA-R-mediated
2000). MSG can be added at concentrations of up to 10 g
neuronal damage, or do elevated levels of glycine produce
per kg food (European Parliament and Council Directive
similarly deleterious effects when binding to the glycine site
95/2/EC). Ca. 3 g MSG are added per kg potato chips (Greiff,
of the NMDA-R (the NMDA-R has a glycine-binding site
Bahlsen-Lorenz company, personal communication, 2002),
(Huggins and Grant, 2005))? Is the NMDA-R the only receptor
ca. 3–6 g are added per kg meat products (Kasch, Do
that mediates arcuate nucleus damages? Do oral loads of GLU
company, 2002, personal communication).
exhibit the same effects than parenteral loads of this amino
We used a medium (2.5 g per day per adult animal) and a
acid? Much work is still to be performed, but good reasons
high (5 g per day per adult animal) MSG diet, accounting for
have already been accumulated to reconsider the recom-
some 10%, respectively, some 20% of the daily amount of
mended daily allowances of amino acids and nutritional
food. Yet, rat chow is dried food. Assuming a water content
protein, and to abstain from the popular protein-rich diets,
of some 70% in an ordinary breakfast sausage, 6 g MSG per kg
and particularly from adding the flavouring agents MSG.
meat product equals some 2% MSG in the dry product. Thatis, the medium concentrations of GLU used in our animals,surpassed the concentration that is currently added to
modern industrial food, by only the factor five!
The present study for the first time demonstrates, that a
This work was supported by the Deutsche Gesellschaft fu
widely used nutritional monosubstance – the flavouring
agent MSG – at concentrations that only slightly surpass
and by the European project EURISKED (EVK1-CT2002 -00128).
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Director Development Shorts Networking Tactics For Directors Overview As a follow up to Director Development Short # 150, here are a litany of networking actions for Directors. Discussion Think of your networking efforts as weaving a giant net. Every contact you make, every interaction you have and everything you do serves to add a strand to that net, each making the net a li
Deutsch-Österreichische Empfehlungen zur HIV-Postexpositionsprophylaxe (Stand Januar 2008 – Kurzfassung) An die Möglichkeit einer medikamentösen HIV-Postexpositionsprophylaxe (HIV-PEP) sollte gedacht werden bei o Verletzung mit HIV-kontaminierten Instrumenten bzw. Injektionsbestecken, o Benetzung offener Wunden und Schleimhäute mit HIV-kontaminierten Flüssigkeiten, o ungeschütztem