Monosodium glutamate, otherwise known as MSG, is a controversial food additive designed to enhance flavour.
There are two kinds of MSG. Natural MSG, otherwise known as L-glutamic acid, is derived from a range of plant and animal-based foods found in the diet of most people. It is a harmless amino acid when it is bound with proteins, which allows your body to absorb it slowly and naturally. Manufactured and processed MSG is another story.
Man-made MSG is free glutamic acid, which does not have any protein component to slow down its absorption, which is then mixed with salt. After salt-and-pepper, MSG is now the third most common flavour enhancer. It works by tricking your brain into believing the food you eat tastes good, and this is used by the food industry to make substandard ingredients taste better.
The danger lies in the fact that glutamate is also used as part of your central nervous system as a neurotransmitter in the brain. It helps to regulate the central nervous system and is required for normal brain and organ function. Glutamate is believed to play a role in memory and learning.
By consuming man-made MSG, we are able to flood our bodies with glutamate, which, whilst triggering a “better” taste in our food, also risks interfering with our natural neurological processes.
A spike of MSG can overstimulate brain neurons, leading to both physical and psychological problems. Some people are more sensitive to the effects than others, due to their age, levels of stress or perhaps existing disease, but symptoms of too much MSG include migraines, an asthma attack, stuffy nose, throat swelling, diarrhoea, skin rash, irregular heartbeats or even the mimic of a stroke or heart attack. Tests have shown that a high enough dose of MSG can make everyone experience an immediate reaction.
Long-term exposure of MSG has been implicated in a wide range of conditions (including cancer), such as mood swings, depression, infertility, paranoia, Parkinson’s disease, Alzheimer’s disease, memory loss, obesity, birth defects, retinal damage, learning disabilities and more.
Animal studies in 2006 showed that MSG damages blood vessels, through the action of free radicals, which can lead to weakened arteries and blood clots.
With regard to cancer, the primary concern is that many cancers have been shown to have glutamate receptors. MSG is able to bind to these glutamate receptors, stimulating the growth of the cancer cells.
A paper published in Oxford Journals / International Immunology showed that cancer patients typically have high glutamate levels. They also showed that lung cancer patients with the lowest glutamate levels had the highest survival rates. High glutamate levels also appear to reduce your cells’ ability to absorb another amino acid called cystine.
Cystine is used to make glutathione as well as taurine, which are naturally occurring water-soluble antioxidants that help to detoxify your cells and protect against the damage caused by free radicals.
Glutathione has shown to have excellent anti-cancer properties both in terms of prevention and inhibiting cancer cell growth. Excellent sources of glutathione include asparagus, Brazil nuts and whey protein. Glutathione is also contained in potatoes, carrots, onions, avocados, spinach, tomatoes, broccoli, peppers, oranges, apples, bananas and grapefruit.
The general consensus of the Oxford Journals’ published research is that reducing your glutamate levels should increase your body’s cancer fighting ability.
Supporting this, a study published by the National Academy of Sciences showed that glutamate antagonists (which counteract glutamate) limited the tumour growth in colon cancer, breast cancer, brain cancer and lung cancer cells. Glutamate antagonists also decreased the motility and invasive growth of tumour cells.
In addition, not only can the glutamate itself cause a problem, but two out of the five types of MSG manufacturing process also create low levels of carcinogenic impurities. Manufacturing MSG via acid hydrolysis creates small amounts of carcinogenic mono and dichloro propanols and MSG produced via a Maillard reaction, always contains traces of carcinogenic heterocyclic amines. Heterocyclic amines are the same carcinogens you get in charred or burnt food.
Despite MSG being classified by the FDA as “GRAS”, (generally recognised as safe), the FDA persistently receive complaints of negative side-effects from this product.
Worse still, if you want to cut this additive out of your diet, food manufacturers have become increasingly crafty about how they label it. If it isn’t labelled as MSG or monosodium glutamate, it may be disguised as textured protein, sodium caseinate, hydrolysed vegetable protein and soy protein isolate. Sometimes, it may not even be listed. For example when it is added to some raw fruits and vegetables in the preservative wax coating.
The only way to truly avoid it altogether, is to prepare your own foods from fresh ingredients. Anyone considering avoiding monosodium glutamate should also avoid aspartame, because it breaks down into glutamate, phenylalanine and methanol.