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MSG and Obesity: fat rats, brains and eyeballs

(Flavour enhancer 621) by Toni Reid

A certain substance, when injected into baby mice and rats, causes them to mature into unnaturally obese adults. In animal testing, this same substance has been shown to cause brain cell destruction and retinal deterioration. In fact, this stuff is so good at killing brain cells, that's what some experimental scientists use it for!

Unfortunately for us, it is also added to a wide range of foods available in our local supermarkets, and fast food outlets. It even finds its way into some medical products and is an ingredient in an agricultural spray. What is the purpose of this additive, you may want to know? Does it protect us from the horrors of food poisoning? Nope. The only reason it's there, is to make you eat more of that particular food. In that case, you say, I'll just avoid it. Well, good luck. This substance has pervaded many commonly consumed food products, including: flavoured potato chips and snack foods, savoury flavoured crackers, flavoured noodles, powdered soup, tinned soup, flavoured dried rice meals, powdered stock, powdered gravy or sauce mixes, salt replacers, soy sauce, tinned/bottled cooking sauces, salami, sausages, frankfurters, ham, bacon, vegetarian sausages/patties, powdered 'sports' shakes, weight loss shakes, and most disturbing of all, infant formula. It may also lurk in the frozen foods section, watch out for it in - burger patties, fish pieces, chicken nuggets, pizza, prepackaged meals and meat pies. In a cunning move, not all of these products list the presence of this additive plainly on their labels.

The name of this substance is probably familiar to you - Monosodium glutamate, or MSG for short. MSG is the sodium salt of the amino acid glutamic acid. It is classified as a flavour enhancer, which means it does not protect the food from spoiling or have any other technical use, except to make you want more of whatever food it is in. You may be shaking your head, and saying: Hasn't this been around for yonks? If there's a problem, why haven't we heard about it before? Actually, all the information is out there, freely available - in published scientific studies, in books and on web sites. Of course, unless you know there's a problem, you wouldn't be looking for it. And mostly, stories about MSG fail to make the major papers, magazines and television.

One explanation is that the companies whose products contain MSG, advertise in these various different forms of media, and could threaten to take their budgets elsewhere. Board of Directors members for television networks and printed media, may also have shares in food companies.

In 1991, American show Sixty Minutes aired an item on MSG. Producer Don Hewitt said he'd never experienced such pressure by industry to 'bury' a story, and since then they haven't gone near a story on MSG.

The New York Times, the Chicago Tribune and the Baltimore Sun have all refused to publish stories concerning MSG, most likely due to the ubiquitous presence of the Glutamate Industry.

Over here you may find the odd snippet tucked away in a health magazine, but not a whisper in the mainstream.

But thanks to the Internet, the information is slowly trickling down. A spot of Googling reveals that way back in1957, a study by opthamology residents Lucas and Newhouse found that a single injection of glutamic acid [MSG] caused severe retinal lesions in newborn mice. In 1968 a letter to the editor of the New England Journal of Medicine described the symptoms of headache/migraine and extreme thirst [known as 'Chinese Restaurant Syndrome'] that have come to be associated with the over consumption of MSG.

Then, in 1969 a study by Dr. John Olney showed that MSG caused brain lesions and obesity. Recent work by neurosurgeon Dr. Russell Blaylock, and the publication of his book 'Excitotoxins, the Taste that Kills' explains just what it is about MSG that you may want to avoid. Now we have to get a bit technical, because it's necessary to understand why MSG is so dangerous. Glutamic acid is a natural substance which is found in food, and used in the brain as a neurotransmitter, vital to the transmission of nerve impulses essential for cognition, memory, movement and sensation. The trouble with MSG, is that it contains what is known as free glutamic acid. Normally glutamic acid is bound to protein in your food, and the body controls the amount that is converted from the protein, only releasing what is needed. Free glutamic acid is not subject to this regulatory process, and excess of it in the brain causes damage by over-exciting the neurons, culminating in their death through exhaustion. Hence the name 'excitotoxin'.

Health professionals now believe that excitotoxins are implicated in the development of Parkinsons disease, Alzheimers disease and Amyotrophic Lateral Sclerosis [Motor Neuron disease]. In 1998 in Bethesda, Maryland, a medical conference was held solely to discuss the role of Glutamate in many central nervous system disorders.

Manufacturers of MSG generally counter this type of information highlighting the potentially harmful nature of their product, with their favourite fairy story: that MSG can't enter the brain because of the blood/brain barrier [a special capillary structure designed to exclude toxic substances from the brain.] Dr. Blaylock refutes this assumption. 'For example' he says, ' it is known that the brain, even in the adult, has several areas that normally do not have a barrier system, called the circumventricular organs.'

The phrase 'terminological inexactitude' must have been created for the food industry. To keep us in the dark concerning the amount of free glutamic acid in the products we buy, the food technicians devise numerous names for it to masquerade under- 'natural flavourings', 'seasonings', 'yeast extract','autolyzed yeast', 'textured protein', 'maltodextrin', 'malt extract', 'gelatin' , 'soy protein isolate', 'whey protein', 'carrageenan', 'sodium caseinate 'and 'calcium caseinate'.

Another vehicle for the delivery of free glutamic acid is 'hydrolysed vegetable protein'. This culinary delight is made by boiling vegetable scraps in a vat of sulphuric acid for several hours. The resultant powder is scraped up, and added to your food.

All of these additives need not be labelled as MSG, because they haven't actually added it to the product, but instead, created free glutamic acid during processing. Though it's all the same when you eat it.

Clear labelling is important if you are sensitive to MSG. Up to 25% of the population is sensitive to MSG, some may have violent reactions which can include: sudden asthma attacks, seizures, migraines, racing heart beat [tachycardia], hives, headaches and diarrhoea. A MSG sensitive Los Angeles man lunching at a local restaurant, passed out, suffered severe respiratory distress, which progressed to a full cardiac arrest, all due to his soup being made from a 'beef flavouring' base which unknowingly contained MSG.

For former investment banker, Jack Samuels, eliminating free glutamic acid from his diet was a godsend. Suffering from symptoms similar to Alzheimers disease, he and his wife Adrienne managed to effect an immediate cure after excluding all forms of MSG from his food. Highly sensitive to free glutamic acid, Jack has lost consciousness on thirty occasions due to MSG. Together, Jack and Adrienne head the 'Truth in Labelling Campaign', dedicated to revealing the hidden glutamic acid in food.

Yet those involved in the manufacture of MSG, still refuse to acknowledge the vital difference between free glutamic acid and glutamic acid. Their stance is: 'it occurs naturally, so therefore it is safe'. Since the active ingredient was isolated from seaweed in the early 1900's, the production of MSG has become a massive business. Now a cheaper microbial fermentation method utilizes bacteria which excrete glutamic acid into a liquid medium. Millions of tons of the stuff are used worldwide, every year. And millions of dollars of profit are at risk if this additive is proven to be hazardous.

With the publication of Dr. Olney's studies in 1969, the glutamate industry was faced with an assault on the safety, and therefore the marketability of their product. The major players in the glutamate industry decided they needed to counter with some good PR. This resulted in the formation of The International Glutamate Technical Committee [IGTC], which hands out financial assistance to researchers, designs and implements research protocols and then distributes the results of these studies to promote the use and safety of MSG.

The glutamate industry also have innocuous sounding nonprofit organisations to act as agents for them, such as The International Food Information Council [IFIC] and the International Life Sciences Institute [ILSI]. Their function with regard to MSG, is to deride any research or person who is critical of the safety of glutamates, and also to distribute glossy brochures encouraging the use of MSG to nutritionists, dietitians, allergists and the media. The IFIC web site contains glowing references from the FDA, the AMA et al, espousing the safety of MSG, along with indoctrination on the joys of irradiated and genetically engineered food. A visit to the web site of the ILSI confirms that Ajinomoto, a major producer of MSG, is a member and that they are “supported primarily by their industry members”.

Representatives of the glutamate industry have infiltrated organisations such as the FDA Food Advisory Committee, the Medical Advisory Board of the Food Allergy Network, and advised numerous other associations, committees and councils convened to ascertain the safety of food. So it was not surprising when in1998, a citizens petition with the aim of labelling all free glutamic acid content in food was defeated in court by the FDA. The petition was backed by researchers, physicians, the Truth in Labelling Campaign and MSG sensitive consumers.

According to Dr. Adrienne Samuels of the Truth in Labelling Campaign, animal studies commissioned by the glutamate industry have shown deliberate manipulation to assure the desired outcome. It's the old adage - he who pays the piper, calls the tune.

Perversions of testing protocol included

  • the elimination of subjects likely to react to MSG, to test for reactions to MSG.

  • limit reporting time for adverse effects to two hours after ingestion.

  • Placing aspartame, (another excitotoxin, used as an artificial sweetener, which causes similar symptoms to ingestion of MSG) in the placebo. This ensured equal reactions to both the placebo and the test substance.

  • Knowing that brain lesions could not be identified if examination of test animals brains were done 24 hours after the insult, they routinely did not analyse them until this time had elapsed.

When those scientists back in the sixties discovered that MSG causes obesity, they found it was a handy way to make rats and mice fat, so they could use them to study diabetes. Injecting the pups under the skin with MSG, led to them becoming overweight adults. In the newborn, monosodium glutamate destroys the arcuate nucleus of the hypothalamus, which effects the regions in the brain responsible for regulating food intake. Thousands of these creatures are created every year, to test possible cures and medications for diabetes.

The pertinent question is, can MSG effect humans in the same way as rats? After all, we use rats to assess safety of medicines and toxic substances, so could there be a connection between the epidemic of obesity, and our exposure to MSG?

The 2002 MOH Children's Nutrition Survey found that one third of New Zealand children between 5-14 years were overweight. Is obesity only caused by genetics, a poor diet and /or lack of physical activity? Perhaps there is some other factor here, that hasn't been taken into account?

In mid 2005, M. Hermanussen and JAF Tresguerres published a study titled 'Obesity, Voracity, and Short Stature: the Impact of Glutamate on the regulation of Appetite'. This presented experimental support for a hypothesis regarding the use of elevated amounts of glutamate in the diet. They found morbid obesity is associated with short stature, which in turn is associated with low levels of growth hormone. Growth hormone levels are lowered in newborn rats when injected with MSG, and in rats whose mothers received MSG whilst pregnant. They also observed rats kept on a high MSG diet demonstrated marked voracity. In conclusion, they felt there were good reasons to avoid MSG, at least until more studies could be carried out. Additionally, Hermanussen and Tresguerres have presented clinical evidence that the use of anti-glutamate drug Memantine, normalises binge eating disorders within hours by blocking the action of glutamate.

From the moment they are conceived, our kids are exposed to free glutamic acid, as it has no trouble crossing the placenta. After a child is born, it may be fed with a formula milk containing free glutamic acid in the form of hydrolysed protein or soy isolates. Next stop for exposure is immunisation. Both the Chicken Pox and MMR vaccines have monosodium glutamate listed as ingredients. A little later when the child moves onto solid foods, savoury snack foods may become a regular part of the diet. These are almost certain to contain MSG. As the child grows they will continue to be exposed to MSG if they eat meals made from tinned, packeted or frozen ingredients, or dine out at restaurants. To exclude it totally from their diet would require extreme vigilance.

Maybe it's a coincidence that the recent passing of the 'Personal Responsibility in Food Consumption' Act in America, protects food companies from litigation? This legislation protects the seller of food from civil liability, where it may be claimed that an individual's weight gain resulted from the long-term consumption of a certain food. Previously, I thought that people who sued fast food companies for making them fat were out of line. After reading about MSG treated mice, I'm not so sure.

The disadvantages of MSG in your diet extend further than damage to your mental faculties and obesity. A recent study at the Hirosaki University School of Medicine in Japan, investigated the effect of a diet high in glutamate on the eyes, again using rats to evaluate the damage. The results were startling. After six months on the diet, the retinal layers were noticeably thinner, up to 75% in some cases. The lead researcher Hiroshi Ohguro, speculates that this may have something to do with the high rate of normal tension glaucoma in eastern Asia.

Joseph Sowka, an Associate Professor at the College of Optometry, Nova Southeastern University also believes excitotoxins are a factor in the development of glaucoma, as he has observed a two fold increase in glutamate in the eyes of people suffering from the disease.

Findings presented at the Bethesda Glutamate Conference linked elevated retinal glutamate in diabetics to damaged neurons, eventually leading to loss of vision.

A study in 1996 by J C Blanks et al, found that sufferers of Alzheimer's disease have widespread destruction of their retinal ganglion cells. This is the same area mentioned by Lucas and Newhouse in their initial discovery of the excitoxic behaviour of MSG.

When we notice symptoms of Alzheimer's or Parkinson's, 80 to 90 percent of the neurons involved will already have died. This is because they don't die all at once, but deteriorate gradually over the years, with diagnosis only possible when the damage becomes apparent. Because of this, curing these diseases is presently not feasible, so most medications aim to slow the progression of the symptoms. At the moment there are 18 million people in the world living with Alzheimers. In the USA alone, 4.5million, have the condition, with a projected 13.2 million by 2050! In New Zealand we have about 21,000. Apart from the heartbreak Alzheimers inflicts on those closest to the sufferers, imagine the economic burden of keeping all those people in full time care for many years. Alzheimers may rob you of your memories and ability to look after yourself, but you can live for up to twenty years after being diagnosed.

In years gone by, it was only the elderly who were thought to be at risk of contracting these types of diseases. The discovery of early onset Alzheimers and Parkinsons, means you could come face to face with these disorders in middle age, or even younger. The pattern is the same for ALS, with the juvenile onset form having one known sufferer who is 25.

Apparently unaware of the possible link between neurodegenerative disorders and MSG, the American Dietetic Association recommends the addition of it to meals prepared for senior citizens to stimulate appetite. The recommendation appears in a fact sheet, supported by a grant from Ajinomoto.

Anti-glutamate drugs are currently the most promising avenue in the treatment of Alzheimer's, Parkinson's, glaucoma and ALS. Memantine, a glutamate receptor blocker for use by Alzheimer's patients, protects neurons from glutamate toxicity. A pilot study indicates that some complications of Parkinson's may be relieved by Talampanel, a compound that blocks the actions of glutamate. Riluzole, a treatment for ALS involves anti-glutamate drugs and Copaxone, a possible treatment for glaucoma, protects the optic nerve from the toxic effects of glutamates. While scientists work feverishly to concoct these drugs, ironically, at the same time the food industry is increasing the amount of glutamate in our food supply. Its hard to follow the logic, isn't it?

You would think that fresh fruit and veges would be a safe bet when it comes to avoiding MSG. But that may change with the debut of AuxiGro, a fungicide and growth enhancer, approved in America for use on various crops. AuxiGro contains almost 30% free glutamic acid, and may be used on most fruit, vegetables, nuts and berries and is also popular with growers of wine, table and raisin grapes as it boosts the sugar content. AuxiGro is touted as natural and non toxic by its manufacturer, and the EPA agrees, awarding it a exemption from tolerance on agricultural commodities. What is not yet known is whether Auxigro would contaminate ground water and soil, and how eating and cooking produce treated with Auxigro is likely to affect you. People with a sensitivity to free glutamic acid are understandably concerned about the consequence of inhaling spray drift. The Truth in Labelling Campaign has received reports of MSG- type reactions following ingestion of head lettuce, russet potatoes, broccoli, and strawberries since the use of AuxiGro began. Produce sprayed with AuxiGro has probably been imported for sale here, and it's only a matter of time before the spray itself is available in New Zealand.

It seems absurd that our MoH is giving serious consideration to subjecting herbs, vitamins and minerals to testing and licensing comparable with medicines, when these substances have good track records for safety. Allergens like bee products, peanuts, soya etc must have warnings included on labels, but for some reason free glutamic acid manages to sidestep all of these measures. Still, the MoH are the folks that place outdated mercury-laden amalgam fillings in your children's teeth as part of their free dental care programme. Oblivious to restrictions on the use of mercury based fillings in European countries, and a proposal to ban their use in California, our health boffins ignore research demonstrating links to disease and birth defects. No doubt their reaction to the dangers of MSG will be the predictable platitude- 'our experts haven't found any dangers.' As if we are a different species, and the results of overseas studies don't apply to us!

We delegate responsibility for food safety to various authorities, in the belief that they are acting in our best interests. Food Standards Australia New Zealand [FSANZ] have a tendency to forget their primary objectives, which are:

  • provision of adequate information relating to food to enable consumers to make informed choices,

  • protection of public health and safety

  • prevention of misleading or deceptive conduct.

This is evidenced by an application made to the FSANZ which would have notified customers if MSG was added to food consumed at restaurants and fast food outlets. The proposal was inundated with glutamate industry angst. Public concerns were overwhelmed by numerous submissions from glutamate manufacturers trotting out tired old industry generated data purporting to prove the safety of MSG. One wonders why companies from South East Asia, United States, Europe, South Africa, Japan and the UK and of course the ILSI and IGTC, are involved in deciding our food safety legislation? Why does an obscure little application in Australia and NZ attract so much interest from these overseas companies? Warning the public that MSG has a few nasty side effects, may set a dangerous precedent that could spread to other countries. The decision to reject the application left the NZ and Australian public unprotected, and uninformed, as the primary objectives of FSANZ are overridden in the face of industry pressure.

As I mentioned earlier on, MSG can be used as an ablative tool by experimental scientists. Initially, pharmaceutical grade L-Glutamic acid was used to selectively kill brain cells in test animals, until it was discovered that an inexpensive food additive did the job just as well. It seems there are not many scientists who are willing to openly question the wisdom of dishing up this same substance as part of the family dinner. Even if they won't convict MSG, reasonable doubt has been established, circumstantial evidence has been provided. The verdict is up to you, the consumer.

Will you feed it to your family?

First published in Uncensored Magazine, July Sept 2006


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