Monosodium glutamate (MSG) is a flavor additive, which was originally used in Japanese food and is now commonly added to processed and canned foods such as soups, meats, and frozen food items. Although glutamate is found naturally in fruits, MSG is something that was manufactured using dried kelp to add a extra long-lasting flavor to foods.
Since stored foods tend to lose flavor and taste, flavor enhancers such as MSG slowly started gaining popularity with American processed and stored foods.
What Are The Symptoms Of MSG Allergy?
Earlier known as the “Chinese Restaurant Syndrome,” reactions to MSG were soon given an umbrella term by the FDA: MSG symptom complex. This involves all the symptoms resulting after consuming MSG, such as the following:
1. Headache
This is one of the most common symptoms. People reportedly experience headache either immediately or a few hours after eating foods containing MSG. Such headaches are usually not that severe and require no treatment.
A review of multiple researches, spread over a duration of 40 years, on the effects of MSG showed no consistent data proving the relationship between the so-called cause and symptom.1 Another study was conducted with a high dose of MSG and an unpleasant tasting solution, with gastrointestinal comfort caused by the high doses. But these factors very likely played a bigger role than MSG in causing the headache.2
If the headache is unbearable, taking an antihistamine might help. However, waiting it out is a much better option. Drinking a lot of water will also help flush out the MSG from your body and help reduce headache, among other symptoms.
2. Chest Pain Or Difficulty Breathing
This is one of the more severe symptoms that usually occur within an hour of consuming MSG-added foods. It is common mostly when you consume foods with MSG on an empty stomach or in large doses.3 4
In most cases, however, asthmatics are the ones who have experience a difficulty in breathing after consuming these foods, although there is no substantial research proving this.5
These symptoms require immediate medical attention. And if the chest pain persists for a longer duration, you might need cardiac evaluation and ECG.6
3. Heart Palpitations
This is when you feel like your heart skipped a beat or a quick increase in heart rate. It can be caused by a high intake of sodium, which includes MSG; however, there’s no research proving this.7 8
The increase in heart rate might not be due to MSG but due to food sensitivity, so keep an eye out on what you eat and if your body can take it or not.
The best solution for this is to avoid consuming MSG in any form. Usually, the palpitations stop after a few seconds. If the condition persists, please visit a doctor immediately as it could be an indication of more severe cardiac issues.
5. Swollen Face, Tongue, And Throat
This is a typical allergic reaction in most food allergies and can be due to MSG as well. This usually goes down within around 3 hours after the incidence of the allergic reaction. But in severe cases, the swelling can cause difficulty in breathing. 9
If the symptoms persist, consult a doctor immediately. It might help to avoid drinking anything other than water to help expel MSG completely from your body.
4. Numbness, Tingling, Or Burning
These symptoms are usually seen in the face, neck, tip of the fingers, and other areas and the reactions are generally mild in nature. In severe cases, however, these might lead to swelling and consequently in troubled breathing. The severity mostly depends on the quantity of MSG consumed.10
Since the treatment depends on the cause of the numbness and tingling, you might be prescribed antihistamines.
5. Fatigue, Disorientation, And Weakness
These are common symptoms in sensitive people. You might feel a general weakness and drowsiness. These symptoms are usually not too severe and do not last longer than a few hours, if at all.11 Again, there is inadequate data proving that MSG can be the cause of these symptoms; you might just be too full to want to move!12
6. Obesity
Obesity has been seen as common in those who eat excess MSG. And this is not taking into consideration the amount of calorie intake.
One research observed that people who ate more MSG were likely to gain more weight. Although the cause for this was not obvious, the researchers were of the opinion that these people likely produced more leptin, which causes the body to not process the energy from the food properly.13
7. Nausea
Nausea, another common symptom, can also occur with abdominal pain. Some studies have seen it occurring within an hour of consuming MSG, while others have seen it to begin only after some hours and lasting more than a day.14 In the latter case, the symptoms are severe and require medical attention.
Consume lots of water and avoid eating anything that might trigger further allergic reaction, preferably for the whole day.
8. Flushing And Sweating
Allergic reactions to MSG include facial flushing, hot flashes, as well as excess sweating. This includes feeling redness of the skin or a burning sensation. These symptoms can last for 15 mins or up to a few hours, depending on the severity level.
9. Facial Pressure Or Tightness
This reaction has mostly been seen with the intake of large doses of MSG.15 It can also be seen along with a tightness of the chest. Depending on the severity level, you might need medical attention.
How To Recognize MSG In Foods
So far, the US Food and Drug Administration has reviewed and declared MSG as “Generally Recognized As Safe (GRAS)” three times and maintains this opinion.16 Although the FDA requires all food products to mention MSG in the product labels if used, manufacturers are not required to label substances that contain free glutamic acid, which is a chief ingredient in MSG.
And with the widespread paranoia related to MSG’s effects on health, food manufacturers usually do not mention MSG directly but rather use different names.
Some of the terms used instead of “MSG” are given here:17
- Glutamic Acid (E 620)2
- Glutamate (E 620)
- Yeast Extract
- Anything hydrolyzed
- Any hydrolyzed protein
- Calcium Caseinate
- Sodium Caseinate
- Yeast Food
- Yeast Nutrient
- Autolyzed Yeast
- Gelatin
- Textured Protein
- Soy Protein Isolate
- Whey Protein Isolate
- Anything protein
- Vetsin
- Ajinomoto
- Gourmet powder
- Natural Flavors
What Makes Recognizing This Allergy Tricky?
- Like all allergies, MSG allergy is subjective and works differently for each individual. While you might feel immediate reactions, your friend might not be affected at all or notice symptoms hours later.
- The allergic reaction can also be dose-dependent. You might be perfectly fine with consuming it in small amounts but witness symptoms with heavier doses.
In Conclusion
Researchers have found no conclusive evidence linking MSG and these symptoms. So some other food allergies or inherent health conditions might be causing your reactions. But some studies do accept that a small percentage of people may have short-term reactions to MSG, which is probably a food allergy like any other.18
It might be impossible to avoid MSG completely from your diet because of the use of fertilizers and pesticides, i.e., “growth enhancers,” which can leave a residue of MSG in crops that you unknowingly buy from markets.
So the best way to recognize this allergy is to observe your body’s reaction each time you consume MSG. Decide the right quantity and the frequency of including it in your food depending on what your body can handle, not based on claims of MSG’s side effects.
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