Chinese restaurant syndrome is an outdated term coined in the 1960s. It refers to a group of symptoms some people experience after eating food from a Chinese restaurant. Today, it’s known as MSG symptom complex. These symptoms often include headache, skin flushing, and sweating.

A food additive called monosodium glutamate (MSG) is often blamed for these symptoms. However, despite the countless testimonials and the warning from Dr. Russell Blaylock, a neurosurgeon and author of “Excitotoxins: The Taste That Kills,” there’s minimal scientific evidence showing a link between MSG and these symptoms in humans.

The U.S. Food and Drug Administration (FDA) considers MSG safe. Most people can eat foods that contain MSG without experiencing any problems. However, a small percentage of people have short-term, adverse reactions to this food additive. Due to this controversy, many restaurants advertise that they don’t add MSG to their foods.

MSG is a food additive used to improve the taste of food. It has become an important additive for the food industry because it doesn’t compromise flavor if lower quality or less fresh ingredients are used.

MSG is made up mostly of free glutamic acid, or glutamate, an amino acid found naturally in most foods. It’s produced by fermenting molasses, starch, or sugar cane. This fermentation process is like the process used to make wine and yogurt.

The FDA categorizes MSG as “generally recognized as safe” (GRAS). The FDA also categorizes salt and sugar as GRAS. However, there’s controversy over the lack of oversight the FDA has in the introduction and use of additives by the food industry. According to the Center for Science in the Public Interest (CSPI), many GRAS foods don’t go through the rigorous testing required for this safety claim.

Trans fats were once identified as GRAS until enough research forced the FDA to change the classification. Aside from being used in some Chinese food, MSG is added to many processed foods, including hot dogs and potato chips.

The FDA does require companies that add MSG to their foods to include the additive on the list of ingredients on the packaging. This is because some people identify themselves as sensitive to MSG. However, some ingredients naturally contain MSG, and food manufacturers may choose to use these ingredients to avoid disclosing the name MSG on the ingredient list. If you intend to steer clear of MSG, exclude these main ingredients: autolyzed yeast, textured vegetable protein, yeast extract, glutamic acid, gelatin, soy protein isolate, and soy extracts.

People may experience symptoms within two hours after eating foods that contain MSG. Symptoms can last a few hours to a couple of days. Common symptoms include:

Less commonly, people can experience severe, life-threatening symptoms like those experienced during allergic reactions. Severe symptoms may include:

Minor symptoms don’t require treatment. But you should go to an emergency room or call 911 right away if you experience severe symptoms.

People think MSG is linked to the symptoms previously listed. But this hasn’t been proven.

You may be sensitive to MSG if you become ill after eating Chinese food or other foods that contain it. It’s also possible to be sensitive to foods that naturally contain high amounts of glutamate.

Your doctor will evaluate your symptoms and dietary intake to determine if you’re sensitive to MSG. If you’re experiencing severe symptoms, such as chest pain or difficulty breathing, your doctor may check your heart rate, perform an electrocardiogram to analyze your heart rhythm, and check your airway to see if it’s blocked.

Treatment may vary depending on the type and severity of your symptoms.

Treatment for common symptoms

Mild symptoms usually don’t require treatment. Taking over-the-counter (OCT) pain relievers may ease your headache. Drinking several glasses of water may help flush the MSG out of your system and shorten the duration of your symptoms.

Treatment for severe symptoms

Your doctor may prescribe antihistamine medications to relieve any severe symptoms like difficulty breathing, swelling of the throat, or rapid heartbeat.

A 2008 study in Obesity linked MSG intake with weight gain, so it’s likely best to minimize your overall intake. Ask your doctor if any amount is safe for you. You may need to avoid foods that contain MSG if you’ve experienced severe symptoms after eating foods that contain it. So, read the list of ingredients on food packages. When you eat at a restaurant, ask if they add MSG to their foods if they don’t identify foods on their menu as being MSG-free. Also, if you think you’re sensitive to foods that contain high amounts of glutamate, talk to your doctor or dietitian about eating a special diet that eliminates foods containing a lot of it.

If your symptoms were minor, you don’t necessarily have to stop eating the foods you enjoy. You may be able to reduce your symptoms by eating only small amounts of foods that contain MSG.