As usual it takes a couple cases back to back to throw me into writing an overdue blog. In this case, some mysterious atypical migraines for which the patient could not figure out any trigger.
There is a lot of confusion about MSG and the reactions that people can get from it.
First, probably helpful to review what MSG actually is and what it does. MSG stands for monosodium glutamate. It's both a naturally occurring substance of food aging and fermenting, as well as a strong chemical additive that is added to a large variety of foods to enhance taste, palatability, and the desire to eat more processed foods. The glutamate part is also an excitatory neurotransmitter, which when combined to the monosodium bit makes it very more apt to cross the blood brain barrier and dump into your central nervous system where it will act as a strong stimulus to brain cell electrical firing.
Patients can have varying degrees of sensitivity to MSG. For some people, they might not know the difference if they have a small amount and have no particular sensitivity. For other patients, there reaction ranges from mild to severe. Patients who are more likely to have a severe reaction to MSG are people who have blood brain barrier weakness, such as patients with previous concussion, certain medications, and certain type of chronic infections and autoimmune tendencies. For those people, the MSG can cross the blood brain barrier, create a sort of electrical storm in the brain that drains the battery of brain cells, and lead to widespread random brain activities that can manifest as migraine headaches, with a lot of other unusual symptoms such as pain, tingling in their body, and a lot of autonomic symptoms such as nausea and G.I. upset. For some people the MSG induced symptoms can last a few days.
MSG actually does occur in very small amounts in natural foods that have been aged and fermented in particular. However that is rarely the culprit. MSG used as a food additive occurs in much larger amounts than what people would typically see in unaltered foods.
Where the real problem comes in is that MSG is often not labeled as MSG in food. Below is a good reference website that lists all the names under which MSG can be labeled, making it a real challenge for patients to pinpoint MSG as 1 of the triggers to their headaches. I have several patients who have printed the list in a wallet size cards that they carry with them when they shop. To give you an example of common MSG additives:
• Autolyzed yeast
• Autolyzed yeast protein
• Carrageenan
• Pectin
• Sodium caseinate
• Soy isolate
• Soy sauce
• Textured protein
• Vegetable extract
• Yeast extract
• Yeast food
https://www.prevention.com/food-nutrition/a20472934/other-names-for-msg/
