MSG intolerance — What foods to avoid?

Dear Reader,

Chinese delivery on its way? Just opened that can of soup? Better call it a night. Monosodium glutamate (MSG) is commonly used to enhance flavors in Asian food, as well as processed meats, canned vegetables, and soups. The U.S. Food and Drug Administration (FDA) requires that food with added MSG be labeled as containing "monosodium glutamate" on food labels (typically found at the bottom of the ingredients list) and on restaurant menus. Nevertheless, as you pointed out, it may be difficult to work out what exactly is okay to eat.

MSG is the sodium salt of L-glutamic acid, an amino acid that is synthesized by the body and has a critical role in human metabolism. Some individuals may experience what is known as MSG symptom complex after eating foods with MSG. According to the FDA, this adverse reaction occurs when individuals consume large quantities of MSG (three grams or more), especially on an empty stomach. People who have severe or poorly controlled asthma may also be more sensitive to MSG. The following are signs of MSG symptom complex (some people may have more severe reactions):

• Headache
• Flushing
• Sweating
• Facial pressure or tightness
• Numbness, tingling, or burning near or in the mouth
• Rapid, fluttering heartbeats
• Chest pain
• Shortness of breath
• Nausea
• Weakness
  Adapted from Monosodium glutamate (MSG): Is it harmful? by the Mayo Clinic.

In addition to avoiding foods with added MSG, individuals who have MSG intolerance/allergy may also choose to avoid foods containing free glutamate, which is formed when proteins are broken down. This is because free glutamate may combine with free sodium to create MSG. Food that contains naturally occurring free glutamate does not have to be labeled, but includes:

• Tomatoes and tomato juice
• Grapes and grape juice
• Other fruit juices
• Potatoes
• Peas
• Cheeses such as Parmesean and Rocquefort
• Mushroooms

It may also make sense to avoid foods that contain autolyzed yeast extract, sodium caseinate, hydrolyzed plant protein, and hydrolyzed vegetable protein (HVP). Fortunately, hydrolyzed protein must be listed on food ingredient labels.

You may also want to consider discussing this with a healthcare provider, who may make a referral for a registered dietician.

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