What’s the Difference Between Glutamic Acid and Glutamine?

Both glutamic acid and glutamine are amino acids. And while their names sound similar and they both come from the same family of amino acids known as the glutamates, they are different. Glutamic acid is best known as a component of monosodium glutamate (MSG), while glutamine is often used in supplement form by athletes to help improve immunity and recovery.

Here is how glutamic acid and glutamine function in the body:

Glutamic Acid

Glutamic acid is considered a nonessential amino acid, which means your body is able to produce it on its own and you don’t need to get it from the food you eat, according to MedlinePlus. It is an important brain neurotransmitter that’s needed for learning, memory, and general brain function. Glutamic acid is also being studied for its ability to decrease or prevent nerve damage caused by anticancer drugs, according to the National Cancer Institute.

Glutamic acid is found either as a free amino acid or as part of a protein in food. L-glutamic acid is found in animal proteins; plant proteins contain it in higher amounts, according to a 2022 review. It’s also the primary component in the flavor enhancer monosodium glutamate, so it’s found in certain processed foods as well.

MSG occurs naturally in umami-rich foods like tomatoes, anchovies, mushrooms, and Parmesan cheese, according to Harvard Health Publishing. It can also be made by fermenting starch, sugar beets, sugar cane, or molasses into an odorless white powder that can be sprinkled into your food like table salt.

While most people can eat a meal with MSG without a problem, less than 1 percent of them may be sensitive to MSG and experience symptoms, including headaches, skin flushing, sweating, nausea, numbness, and fatigue within a couple of hours of ingesting it.

Glutamine

Glutamine is the most abundant amino acid in your body. Your body makes it, and it is also present in meat, dairy, red cabbage, nuts, and tofu, according to the Cleveland Clinic.

Glutamine supports your immune system; white blood cells use glutamine to fight infections. This amino acid also plays a key role in repairing damaged tissue, helps maintain a healthy gut by strengthening the cell barrier that prevents your intestines from becoming damaged, and helps transport nitrogen (a key element that’s important for many different functions) around your body.

While your body can make glutamine, it is considered a “conditionally essential amino acid,” according to the Cleveland Clinic. Your needs go up when your body is stressed, such as during illness, when dealing with digestive problems, and after intense exercise. At these times you may need to supplement with glutamine. (It is common for athletes to take glutamine supplements.)

As with any dietary supplement, consult your doctor before taking.