In the food industry, great interest has been garnered over the use of a particular ingredient which has caused great controversy overtime. That ingredient is Monosodium Glutamate (MSG). It’s often used as a flavour enhancer. Although additives can improve the taste of many foods, it does carry a threat of causing allergies, food intolerance and even certain conditions among some individuals.
What exactly is MSG?
MSG is a crystallised water-soluble kind of sodium salt made up of the amino acid “glutamate”.
Glutamate is present in nature both in its free form and usually bound to peptides and proteins. The free form is used as additive and is responsible for the flavour enhancing properties. The bound form does not have any effect on taste and is considered an excitatory neurotransmitter (the ones that keep you alert and awake) as they mediate many signals in the brain and is involved in normal brain function such as cognition, memory and learning.
Commercially, MSG is made by fermenting molasses, sugarcane, corn sugar or starch. MSG can also be obtained from natural protein-rich foods such as seaweeds.
How does MSG work?
There are glutamate receptors present in many parts of our body like the brain, tongue and other peripheral tissues. The MSG used in food stimulates the glutamate receptors of the tongue to give a “meat-like” or “umami” taste to foods.
MSG – Chinese Restaurant Syndrome (CRS)
MSG consumption has been linked to the term “chinese restaurant syndrome” since 1968. This syndrome is caused due to body’s intolerance to MSG. Although the use of MSG in chinese food is well known, other cuisines, processed foods and many fast foods also contain it.
It is still considered as a common type of food intolerance that may possibly affect many individuals.
Who can be more susceptible to MSG Symptom complex?
- People with Respiratory problems like Asthma.
- People with known immunity problems with histamine that causes allergies to additives.
- People with intestinal problems like Coeliac disease.
- People with a sensitive stomach to additives.
Signs and Symptoms of CRS
The type of allergic reaction, severity and frequency of symptoms can vary from person to person. Sometimes multiple symptoms can occur at the same time.
- Neurological system: anxiety or panic attacks, blurred vision, depression, dizziness, excessive sweating, fatigue, hyperactivity, irritable, poor concentration, sleep disturbance, mild to severe headaches, migraines, tiredness and leg cramps, numbness of the upper body, head and neck.
- Skin problems: eczema, hives (urticaria), tissue swelling, tongue/ throat swelling, atopic dermatitis, facial flushing and burning, and angioedema (quick swelling of tissue under the skin).
- Gut related problems: bloating(gas trouble), burning mouth or tongue, constipation, diarrhoea, indigestion, mouth ulcers, nausea, vomiting, abdominal pain, cramping and irritable bowel syndrome.
- Respiratory symptoms: wheeze, cough, blocked nose and sinuses, hay fever, sneezing, rhinitis (inflammation of mucosal membrane inside the nose), unstable asthma, and laryngeal oedema.
When should you seek medical care?
Mild symptoms usually subside without treatment, however if symptoms are severe such as excessive swelling of the throat and tongue, difficulty in breathing and raised heart rate. It is best to immediately seek medical care to prevent the complication of allergic shock which is also known as “Anaphylaxis”. It is a potentially life-threatening allergic reaction with excessively severe symptoms associated with the MSG intolerance.
Diagnosis of MSG intolerance?
- Medical evaluation (clinical assessment) can determine if the symptoms are not due to some other identifiable cause or disease process.
- Heart rate and ECG-Electrocardiogram may be recorded to check the normal heart rhythm.
- Respiratory status will be checked for bronchospasm (narrowing of the airways).
- Skin prick tests (or RAST) are used as a standard way of detecting allergen-specific IgE (a type of antibody produced in the body).
Prevention and treatment of MSG intolerance
Drinking water: Water can help flush out any allergens from the body especially MSG. It can reduce the impact and delay the occurrence of the allergic reaction.
Elimination Diet: You can be put on a diet that excludes natural salicylates, amines and glutamate, as well as additives such as preservatives, colourings and MSG. This is to see if your symptoms improve with time.
Medication: Medical care can involve the use of prescribed medications that can help reduce the symptoms of allergic reaction.
Although, a reasonable amounts of such foods can be eaten among mild symptomatic individuals. It is best to avoid it as much as possible to prevent further complications.