Preemptive apology: I know discussing MSG is tired and overdone, and I'm not trying to rehash the old arguments. Instead, I want to see if anyone can help me solve a dilemma that I'm very motivated to solve by figuring out how my understanding is incomplete/wrong. I have a few hypotheses that might explain how I might be mistaken, and I am hoping some of you will help me weed out the sense from the nonsense. Of course, it would be sweet if my current understanding is correct, because then I have an argument to include MSG in the paleo diet. Which would be sweet.
The dilemma: Virtually all research studies have shown that MSG in normal concentrations has no effect on the overwhelming majority of people, BUT a small but significant percentage of people (who I respect and believe) are very adamant about its negative effects. This contradiction really bothers me.
The Motivation: I really, really enjoy that savory MSG deliciousness (I keep it on the table in a third shaker...unless we have company and my wife hides it), and it would be so cool if was no more dangerous than table salt. It would be even cooler if it was paleo.
My understanding: The best argument I can think of against the dangers of MSG is basic protein digestion and the presence of glutamate in most animal protein. Protein digestion begins in the stomach and is completed in the first section of the small intestine (duodenum), after which the resulting amino acids are absorbed into the blood stream as they travel further down the small intestine. Of course there are all sorts of specific enzymes and other details we could look at, but the relevant point (I could quote numerous textbooks on this) is that nearly all proteins are completely broken up into their constituent amino acids and that only individual amino acids are actually absorbed.**
The glutamate molecule found in monosodium glutamate is exactly identical to a very common amino acid found in the vast majority of animal proteins.**^ Breaking down these proteins releases the identical molecule that is supposed to be so nasty in MSG. Because of this, I can't understand why those affected by MSG don't get the exact same symptoms from eating proteins containing glutamate. Even very small portions of nearly any animal protein contain many times more glutamate than is found in even the heaviest MSG seasoning. See why MSG is paleo (hopeful tone? If it's in all animal meat, what's wrong with adding a negligible amount in predigested form to our diet? How is MSG production any different than cooking meat (which partially predigests the protein) and adding salt? ...Or maybe I'm wrong for one of the following reasons.
Certain flavors have been shown to produce systemic effects independent of their actual consumption, e.g. sweet flavor and an insulin response. The umami flavor might produce analogous effects and some part of the resulting physiological cascade could be responsible for negative symptoms in a small percentage of people.
If proteins are not always completely hydrolyzed into their constituent amino acids, then it is possible that a high percentage of glutamate from digested protein might be absorbed in the form of small peptides.
Proteins aren???t completely broken down until the duodenum, so maybe free glutamate is absorbed earlier and differently. (I was taught that proteins were only absorbed in the small intestine, but it might be possible that the stomach lining contains amino acid transport proteins--at least substantial levels of mRNA coding for the LAT2 subunit have been measured: http://jp.physoc.org/content/558/2/597.full.pdf.)
The supposed effects of MSG might be caused by differences between the commercial protein hydrolysis used to manufacture MSG and the digestive hydrolysis of humans and not by glutamate at all.
Any thoughts? Should I invest in selling shakers by the trio?
*I have seen attempts by supplement companies to defend protein supplementation by refuting this. For example, claims that the angiogenic inhibiting proteins found in shark cartilage (http://www.encognitive.com/node/12668 ???study performed by supplement company) are absorbed in polypeptide form, but I am unaware of any study to that effect in a reputable journal.
** In fact, the inability to completely break down certain proteins (e.g. gluten, casein) results in disease (e.g. celiac disease, cystic fibrosis) because of the intestine???s inability to absorb the resulting incompletely digested protein fragments.
**^Some people mistakenly distinguish between glutamate and glutamic acid, but they really are the same molecule plus or minus a hydrogen ion depending on the pH of their environment. When glutamate enters acidic environments of low pH, it forms a bond with a hydrogen ion becoming glutamic acid. Glutamic acid loses that same hydrogen in alkaline environments with a high pH.-
asked byDan_9 (122)
Get FREE instant access to our Paleo For Beginners Guide & 15 FREE Recipes!
on March 02, 2012
at 11:50 AM
Why would you want to voluntarily chase a known excito-toxin? Why would you voluntarily eat something which the crap-in-a-box food-like-industrial-product industry uses to get you addicted to their product?
Certainly, in limited amounts, the naturally occurring versions of glutamate, i.e. in mushrooms, or certain cheeses isn't going to be too terrible as long as it's balanced by GABA, but in free from, or large quantities, it's pure evil.
Would you, for example, chase aspertame, something which breaks down into formaldahyde, and is a suspected carcinogen, and destroys brain cells via excitation? MSG's just it's less powerful, slightly less brawny brother.
on May 24, 2011
at 12:33 AM
MSG and excitotoxins(another term for it because of the effects it has on brain neurons) is a very complex subject. You're going to need to read some more scientific literature to completely understand it but I hope this post from truthinlabeling will shed some insight for you.
If you still need to understand it more I urge you to read the book "Excitotoxins: The Taste that Kills" by Russell Blaylock MD. It's a great read and this book while shocking really helps you understand what we're dealing with here. Those in the know want to get this information out but there is plenty of money being spent to keep people silent about it so people keep consuming this addicting crap we call "MSG" or "factory processed L glutamate". It's NOT natural and here's why:
Glutamic acid is an amino acid found in abundance in both plant and animal protein. In humans it is a non-essential amino acid, i.e., the body is capable of producing its own glutamic acid, and is not dependent upon getting glutamic acid from ingested food.
Glutamate is glutamic acid to which a mineral ion has been attached. (Researchers call this mineral ion a ???salt???.) If the mineral ion is sodium, the glutamic acid becomes sodium glutamate. If the mineral ion is potassium, the glutamic acid becomes potassium glutamate.
In addition to its role as a building block of protein, glutamic acid serves as a neurotransmitter vital to the transmission of nerve impulses in many parts of the central nervous system. Under certain circumstances, glutamic acid becomes a neurotoxin, causing neuron degeneration and cell death which may be followed by neuroendocrine disorders.
When protein is digested, the glutamic acid in that protein is released for use in the body. If there is need, additional glutamic acid can be synthesized from other amino acids contained in ingested protein. If an individual never ingested protein with glutamic acid in it, that individual could synthesize all the glutamic acid needed for body function from other amino acids. The human brain is also capable of synthesizing glutamic acid according to its metabolic needs, from endogenous materials. Glutamic acid is referred to as a non-essential amino acid because a healthy human can manufacture/synthesize all the glutamic acid needed for normal body function from other amino acids.
What is MSG?
MSG is glutamic acid that has been produced outside of the human (or animal) body. But when glutamic acid is produced or created in this way (outside of the human body), it differs significantly from the glutamic acid found in unadulterated, unprocessed, unfermented protein or released from unadulterated, unprocessed, unfermented protein during digestion. Glutamic acid found normally in the human body (and in all higher organisms) is glutamic acid in the L form, i.e., L-glutamic acid. Glutamic acid that is produced outside of the human body is made up of L-glutamic acid and an array of unwanted by-products often referred to as impurities. L-glutamic acid produced outside of the human body is always accompanied by impurities such as D-glutamic acid and pyroglutamic acid; and when L-glutamic acid is produced by way of acid hydrolysis, carcinogenic mono and dichloro propanols inevitably accompany it.
All manufactured free amino acids are accompanied by impurities. The fact that glutamate produced outside of the human body is categorized as food grade or pharmaceutical grade (99% pure) attests to the fact that impurities always accompany amino acids produced outside the body.
MSG fed to the very young has been shown to cause brain damage and subsequent learning, behavior, and endocrine disorders such as reproductive disorders and gross obesity. Ingestion of MSG by people of all ages will cause adverse reactions when people ingest amounts that exceed their individual tolerance levels. Eating protein (which will contain bound glutamic acid that is L-glutamic acid, only) does not cause either brain damage or adverse reactions.
on March 02, 2012
at 12:04 PM
Little known fun fact- When Rome was an empire, the Romans loved a nasty sauce made from fermented fish, and it turns out one of the products of the processing was that it made MSG. And yes, they kept it in a jar on the table...
on March 02, 2012
at 10:40 AM
The research is nonsense, often is! MSG is a big "no." Its bad for the thyroid.
on May 23, 2011
at 11:37 PM
I can't tell you the science but my wife will get a migraine if she eats any amount of MSG. 100% consistent - within about 15-20 minutes of consuming it she starts to feel it. She has no such ill effects from any meat (with or without added salt).