MSG, or Monosodium Glutamate is a salt
of the amino acid - Glutamic Acid (glutamate). A salt is the chemical name for a
molecule held together by opposite charges. Basically one (mono) sodium atom is
"stuck" to the amino acid glutamate.
What is an amino acid?
Amino acids
are often called the building blocks of life because it takes many of them linked together
in a chain to create a protein. DNA tells the body how to make the chain and in what
order the amino acids must line up. Some amino acids must be eaten because the body
cannot make them (essential), some the body can make (non-essential), and yet others are
able to be made during some times, but not others (conditionally essential). The
life processes are all dependent on proteins which play critical roles in the body as
structure, messengers, enzymes, and hormones.
Proteins are globular and clumpy
because the amino acid chains fold in on themselves. This is how the immune system
recognizes proteins. They are large compared to single amino acids, and they are
uniquely shaped. The immune system does not recognize tiny MSG as an
allergen. However, trouble can begin because the body can attack the larger enzymes
like GAD, responsible for turning excess MSG into GABA.
What is an enzyme?
Enzymes are simply proteins with
interesting day jobs. Enzymes help make things happen by helping to create other proteins
and by helping break them down too. Enzymes are not straight chains, they are
globular and clumpy, because they are folded into intricate shapes like other
proteins. It is these shapes that help them create and break down other proteins and
compounds.
What is a hormone?
Hormones are extremely potent protein
based messengers that travel around the body connecting the lines of communication between
glands of the endocrine system. These glands direct important functions like
metabolism, growth, and sexual development. It has been found lately that smaller
amounts of hormones are more effective than larger amounts because the body has feedback
mechanisms that don't take kindly to overdoses of hormone. Things shut down because
it is considered a trouble signal if there is too much hormone present. By affecting
the part of the brain - the hypothalamus, that controls the master gland of the body
- the pituitary, MSG may affect hormone production in the body.
Glutamate - Protein
Building Block and Excitatory Neurotransmitter....
Glutamate is just one of many amino
acids used by the body and linked into the chains of protein in the body. However
some amino acids are free to float around by themselves as well as being found linked into
proteins because they serve vital functions - some are neurotransmitters
which carry nerve cell impulses throughout the body. Amino acid neurotransmitters
are like chemical messengers carrying news from nerve cell to nerve cell. Some
amino acid neurotransmitters like glutamate trigger nerve cells to fire, others like
taurine and gamma amino butyric acid tell those firing nerve cells to cease firing.
It is a delicate balance. An important balance. Researchers are finding out
just what happens when that balance tips. In patients who suffer a stroke, for
example, an excess of glutamate in the brain causes the nerve cells to die from
overstimulation. Glutamate blocking drugs are being used to prevent some of this
damage.
How does the body usually
deal with excess amino acids?
Most amino acids if not used right
away, are not stored as amino acids. The body has elaborate means of changing extra
amino acids into other amino acids, and removing nitrogen and changing amino acids into
fuel to be stored. There are processes such as "transamination"
and "deamination" which occur mostly in the liver. In patients with
compromised livers, however, they may have trouble transaminating cysteine, for example,
into taurine, the amino acid that acts counter to glutamate. Also, an excess of the
amino acid aspartate (found in Nutrasweet) may result in excess glutamate, since the body
can convert aspartate directly to glutamate. Aspartate and glutamate affect some of
the same receptors. In a different example, there is an enzyme that the body
uses to convert excess glutamate into another neurotransmitter called GABA. In many
patients with Type II Diabetes, their bodies view the enzyme responsible for turning MSG
into GABA as an enemy and create antibodies to attack it so that it cannot do its job.
This is a problem. The body is compromised in its job of getting rid of
excess glutamate. It again is a question of balance, and what tips it.
Is manufactured MSG a
problem?
According to some MSG opponents the
glutamate added to foods is "bad" and the natural glutamate in our bodies is
"good". MSG sellers argue that MSG is exactly like the glutamate in the
human body, therefore it must always be "good". It is not so simple.
There are contaminants in processed MSG. An anology that can be used is that there
are right-handed amino acids and left handed ones. They are like mirror images of
each other. Processed MSG contains not only the kind of amino acids the body is
used to handling, but mirror image ones too. This may cause problems because it is
like putting the wrong glove on your hand. It's not quite the same. We don't
exactly know what problems this may cause. On the other hand (so to speak) the fact
that glutamate the body is used to handling is also in MSG may present a problem because
an excess of naturally occurring glutamate is well known by neuroscientists to be a
problem in many disease states. Natural glutamate can cause problems we already know
about. The reason food processors "free" glutamate from its bound form, is
that it acts as a neurotransmitter in its free form. The food industry's claim that
free glutamate is as harmless as bound glutamate is disingenuous at best. If it was
exactly the same, they wouldn't need to hydrolyse vegetable protein (split the amino acids
apart).
How do they
make MSG or Free Glutamic Acid?
The
following links explain exactly how the food industry can make free glutamic
acid by hydrolyzing vegetable protein or by fermentation of glucose from
starchy foods. In essence, MSG manufacturers can not only free bound
glutamic acid from foods, but create it chemically.
Food Product Design article
Scientific paper on fermenation formation of MSG
Why do food companies
add MSG to foods?
There are several reasons: