Glutamine is an amino acid synthesized within the body from glutamic acid. Glutamine is a non-essential amino acid, although it can become depleted during illnesses, prolonged periods of stress and excessive exercise. As an amino acid, glutamine is a building block of proteins, which are essential to maintain and build muscle mass. Consequently, glutamine is important to bodybuilders and other athletes as a muscle-promoting nutrient. Glutamine is available as a supplement, although some foods naturally contain it and are good sources.
In addition to being a building block for proteins, glutamine is a primary source of fuel for the cells that line the gastrointestinal tract, especially the small intestine, according to “Biochemical, Physiological and Molecular Aspects of Human Nutrition." By nourishing these cells, glutamine promotes digestive health and immunity, as the lining of the gastrointestinal tract is the first line of defense against pathogenic microorganisms. Glutamine is the most abundant amino acid in the blood and muscle cells, where it also serves as a source of fuel. According to “Nutrition and Diagnosis-Related Care,” glutamine has been used to treat severe burns, Crohn’s disease, ulcerative colitis and to reduce recovery time from physical activity.
The flesh from animals and fish are an excellent source of protein, which can be broken down by the body to yield glutamine. Thus, beef, pork, chicken and all types of fish are rich sources of glutamine and other amino acids. Raw liver and fish, such as sushi, are the most bioavailable sources of glutamine.
Other excellent sources of protein and glutamine include dairy products derived from animals, such as milk, yogurt, eggs and cheese. Ricotta cheese and cottage cheese are especially good sources of glutamine, according to “American Dietetic Association Complete Food and Nutrition Guide."
All types of beans/legumes are protein-rich and good sources of glutamine, especially for vegetarians. Other vegetables that contain glutamine include cabbage, beets, spinach, kale, parsley, wheatgrass and wheat. In general, raw vegetables are richer sources of glutamine than cooked vegetables because proteins and amino acids can become denatured and unavailable to the body, according to “Advanced Nutrition: Macronutrients, Micronutrients and Metabolism."
Snack foods, such as protein bars, and energy drinks often contain glutamine and other amino acids. Protein bars can contain nuts, whey protein powder, soy-derived protein and milk-based protein, all of which are good sources of glutamine.
- “Biochemical, Physiological and Molecular Aspects of Human Nutrition”; Martha Stipanuk; 2006
- “Nutrition and Diagnosis-Related Care”; Sylvia Escott-Stump; 2008
- “American Dietetic Association Complete Food and Nutrition Guide”; American Dietetic Association; 2006
- “Advanced Nutrition: Macronutrients, Micronutrients and Metabolism”; Carolyn Berdanier; 2009
- female bodybuilder image by Steve Lovegrove from Fotolia.com
This article reflects the views of the writer and does not necessarily reflect the views of Jillian Michaels or JillianMichaels.com.