MSG: Troublesome food additive or fantastic flavor enhancer?

1) Hi Alice,

What's the deal with monosodium glutamate (MSG)? What exactly is it, and how bad is it for you really?

2) Dear Alice,

I have recently been told I have a strong intolerance to MSG. But I am having trouble in working out what it is in. Is there any chance you could give me a list of items of food in which MSG is present in? I would be extremely grateful for any help.

Dear Readers,

Kudos to you both for looking to enhance your knowledge on this particular food additive. Monosodium glutamate (MSG) is a sodium salt derived from the amino acid, glutamic acid (also known as glutamate). Although some associate the substance with controversy, the U.S. Food and Drug Administration (FDA) has deemed that MSG is “generally recognized as safe.” While some foods have naturally occuring MSG, other foods have it added to enhance the flavor (more on this in a bit). Ready to learn more about where to find these flavors? Keep on reading!

MSG was discovered in 1908 by a Japanese professor named Kikunae Ikeda when he isolated the substance from seaweed broth and determined that it was behind the broth’s savory taste. Upon this discovery, it was patented and then commercially produced as a flavor enhancer. Many people are able to ingest MSG with no issue, while others may report experiencing adverse reactions after eating foods with the substance. These adverse reactions after eating foods containing MSG are known as MSG symptom complex. Reactions associated with the condition may include headaches, tingling, flushing, heart palpitations, drowsiness, or numbness, among others. Interestingly, while researchers do recognize that some people experience these symptoms, they have been unable to replicate them with any reliability in a lab setting (as compared to a placebo). The good news is that the symptoms are typically short-lived, mild, and don’t usually require treatment. Research has also found that adverse reactions tend to occur when individuals consume large quantities of MSG (three grams or more), which is generally uncommon as foods with MSG typically only have 0.5 grams or less of the additive in them.

Those with a sensitivity to MSG are advised to avoid it. To that end, identifying food products and restaurant menu items that contain MSG may be easiest, as they're required to be labeled as containing the substance. Still, determining exactly what is safe to put on your plate if you’re prone to MSG sensitivity can be a challenge. This is because not only can foods with added MSG trigger symptoms, but some foods with naturally occurring glutamate may also be of concern as well. Foods that contain naturally-occurring MSG include but aren't limited to:

  • Tomatoes
  • Cheeses
  • Autolyzed yeast extract
  • Soy extract
  • Protein isolate
  • Sodium caseinate
  • Hydrolyzed plant protein
  • Hydrolyzed vegetable protein (HVP)

List adapted from the FDA.

Given that the MSG within these foods and ingredients are naturally occuring, they don’t require labeling. However, they also can't be labeled as having “no MSG” or “no added MSG.” Being aware of this labeling distinction can help you avoid products with added MSG and products that contain naturally-occurring MSG.

Lastly, and specifically for Reader #2, you mention that you’ve been told that you have a strong intolerance to MSG. Have you been diagnosed by a medical professional? If not, you might consider speaking with a health care provider to determine if what you’re experiencing is due to MSG. If they do determine that you do have a sensitivity and you continue struggle to find foods that are tolerable, you might also consider a visit with a registered dietitian to help you find foods in the grocery store and while eating out.

Here's hoping that this response provides some food for thought,

Last updated Aug 12, 2022
Originally published Aug 09, 2002