Low Glutamate Diet

A low glutamate diet may be required by those who have a particular sensitivity to the substance. Understanding the different sources and types of food that contain glutamate can help sensitive individuals make the best food choices and avoid symptoms of glutamate sensitivity.

A woman is suffering from a headache. (Image: anyaberkut/iStock/Getty Images)

Glutamate As a Food Additive

Glutamate is actually an amino acid that forms part of the building blocks of protein found in all living things. It is essential for life, which means it is not only found circulating in the human body but also in a natural form in many foods commonly eaten. When glutamate is isolated from foods, it has flavor-enhancing properties in the mouth, imparting a savory flavor or "umami" to foods. Glutamate can also be produced artificially and, when combined with sodium to keep it stable, is known as the flavor-enhancer monosodium glutamate, or MSG. A glutamate sensitivity can manifest itself with headaches, nausea, gastric upset and asthma attacks; the onset of these symptoms can occur within hours of eating the food.

Found Naturally in Foods

An important consideration for those wishing to follow a low glutamate diet is that glutamate is found in many foods naturally and not just as an additive. High levels of natural glutamate are found in foods that have been matured, cured or preserved for some time, allowing the proteins to break down to release the glutamate amino acid. The highest concentrations are found in long, matured cheeses, such as Parmesan and Roquefort. Other foods to consider include cured meats, fish sauce condiments and soy sauce. Glutamate is also found in significant quantities in other foods that are not matured in any way. These include mushrooms, ripe tomatoes, broccoli, walnuts and peas. Food products containing these ingredients have a significant quantity of natural glutamate in them and must be avoided if a low glutamate diet is to be followed.

MSG in Processed Foods

Some processed foods contain the artificial additive MSG and these tend to be savory foods, such as stocks, sauces, savory snacks and instant meals. The primary role of MSG is to enhance the savory flavor of the food and make it taste more meaty. MSG is often found in cheaper meat products. To find out if a food contains MSG, look at the food label first. Legislation requires that if monosodium glutamate has been added to a food, the label must declare this in the ingredients listing. However, a food that naturally contains glutamate is not required by legislation to state this on the product label, so knowing what food sources contain MSG is key.

Strategy for a Low Glutamate Diet

If you suffer from glutamate sensititivy, eliminate as much natural and artificial glutamate as possible from your diet and any symptoms should subside. Gradually introduce some of the natural sources of glutamate back into your diet. Carefully note any patterns of symptoms that emerge. By continuing to build this up over a number of weeks, it will likely become obvious whether certain foods are trigger foods as well as how much of certain foods you can tolerate. Using this information, it may be possible to build up a low glutamate sensitive diet for the long term.