What Is an MSG Headache?

An MSG headache is a headache that occurs after eating foods containing the common food additive monosodium glutamate (MSG). This symptom is part of what's called MSG symptom complex, a broader set of symptoms that can occur with MSG consumption. These include sweating, facial pressure, and flushing.

This article reviews the symptoms of an MSG headache, why they may occur, how to treat them, and how to prevent them.

Symptoms of MSG Headache

Most people with an MSG-related headache describe a tightening or even burning head sensation. People will also commonly notice muscle tenderness around their skull.

In people with a history of migraines, MSG can be a trigger. In this instance, people usually report a classic throbbing or pulsating headache.

An MSG-induced headache typically develops within 1 hour of consuming MSG and resolves within 72 hours of MSG consumption. Also, an MSG-induced headache has at least one of the following five characteristics:

• Bilateral (i.e., both sides of the head)
• Mild to moderate intensity
• Pulsating quality (i.e., throbbing)—like a migraine
• Associated with other symptoms including facial flushing, chest and face pressure, burning feeling in the neck, shoulder, and/or chest, dizziness, and stomach discomfort.
• Aggravated by physical activity

Individuals with an intolerance to MSG may also experience a cluster of other symptoms that may include:

• Muscle pains
• Facial pressure
  
• Nausea
• Flushing
• Tingling
  

Why Does MSG Give You a Headache?

The mechanism behind why MSG may give you a headache is not fully understood and more research is needed. MSG is an excitatory amino acid that binds to MNDA receptions in the brain. This activation leads to the release of nitric oxide, which then leads to the dilation or widening of blood vessels around the skull.

A study published in the journal Cephalalgia also found that people who consumed a high amount of MSG—such as a sugar-free soda containing 150mg/kg of MSG—had an increase in their blood pressure, although this was temporary. Chronic daily intake of high doses of MSG may also cause fatigue.

Prevention

For people who are sensitive to MSG, the only treatment is to avoid foods containing MSG. Foods that commonly contain added MSG are soy sauce, canned vegetables, soups, and processed meats.

Though generally regarded as safe by the U.S. Food & Drug Administration, added MSG must be listed in the ingredients list on food packaging.

Look for these terms:

• Monosodium glutamate or MSG
• Hydrolyzed fat
• Hydrolyzed protein
• All-natural preservatives 
• Sodium or calcium caseinate
• Autolyzed yeast or yeast extract
• Textured protein
• Glutamic acid
• Monopotassium glutamate
• Gelatin
• Soy protein isolate
• Soy extracts

When dining out, ask if the restaurant uses MSG ingredients.

Treatment

MSG-induced symptoms are typically not severe and subside on their own entirely within 72 hours. However, if you have mild symptoms do not appear to resolve or continue worsening after 48 hours, speak to your healthcare provider, as it may be something more serious.

To help you get rid of an MSG headache faster, drink only water, and a lot of it—at least half of your body weight in ounces. For example, if you weigh 150 pounds, drink at least 75 ounces of water. Adequate hydration will help your kidneys to process MSG and flush it from your system.

In addition, limit sodium intake until symptoms dissipate. Sodium promotes water retention and will make it harder for your body to release the MSG through urination.

A Word From Verywell

If you suspect MSG is a headache or migraine trigger for you, avoiding it is probably your best bet. Unlike other food sensitivities, it is unlikely that you can build up a tolerance for MSG. The best way to avoid MSG is to read food labels and inquire at restaurants if MSG has been added to any foods.

Keeping a diary of your headache symptoms and possible triggers can help you and your healthcare provider to pinpoint the causes of your headaches and develop the right treatment plan for you.