Glutamine:
» metabolism:
Glutamine is considered a conditionally essential amino acid since it is essential during periods of excessive stress (injury, septicemia, acute burns, inflammatory bowel disease, etc.). It is the most abundant amino acid in the skeleton, muscle and blood. Glutamine is 10-15x more concentrated in the brain than in the blood. It is synthesized from glutamic acid.
» function:
Glutamine is essential and is the preferrred source of energy for enterocytes of the GI tract. With alanine it provides over 75% of the fuel for enterocytes during acute stress. It is also a preferred source of energy for the brain. It is involved as a neurotransmitter in the brain.
In athletes who overtrain, glutamine can become depleted. This results in increased infections, especially respiratory type infections.
Other cells which rapidly divide, including lymphocytes, macrophages, thymocytes, rely on glutamine as well. It is also involved with acid base balance in the body.
In the intestines it is critical for repair of tissue, especially in returning the tissues normal permeability characteristics.
Glutamine is essential for the synthesis of vitamin B-3, and is a cofactor in the metabolism of benzoates. It is essential in the metabolism of uric acid and arginine.
» requirements:
RDA: Glutamine is considered only conditionally essential
Average intake in the U.S.: 23 g per day
» food sources:
Best Sources of Glutamine:
Food Amount Mg
Yogurt 1 cup 930
Granola 1 cup 300
Duck 3oz 225
Oatmeal flakes 1 cup 200
Wheat germ toasted 1/4 cup 180
Cheese, cottage 1/2 cup 150
Cheese, ricotta 1/2 cup 120
Pork 3 oz 120
Turkey 3 oz 94
Cheese 3 oz 90
Chicken 3 oz 75
Egg 1 med 70
Wild game 114 cup 67
Sausage 3 pc 66
Meat, luncheon 3 oz 54
Milk, whole 1 cup 33
(USDA: Composition of Foods. USDA Handbook #8 Washington DC, ARS, USDA, 1976-1986)
» therapeutics:
Inflammatory bowel disease especially in extreme weight loss: 6-12 g per day Ideally, it can be added as a powder to drinks to help maintain weight and heal the gut mucosa.
Increased intestinal permeability
Peptic ulcers
Alcoholism: It has been used for years in the treatment of alcoholism. It may decrease cravings for alcohol. (Rogers, L.L., et al. Quar. J of Studies on Alcohol 18:4: 581-7, 1957)
Total Parenteral Nutrition treatment or starvation diet to prevent villus atrophy in the small intestine.
Enhancement of mental function in Alzheimers patients
Cancer: Glutamine may be an essential respiratory fuel for tumor cells. A drug glutaminase which breaks down glutamine is used to treat acute leukemia and lymphocytic malignant cells. Vegetarian diets have sometimes worked in the treatment of some cancers since glutamine is usually on the low side for vegetarian foods.
» toxicity:
Glutamine has very little toxicity.
» contraindications:
None known.
» interactions:
None known.
footnotes
Marz, Russell. Medical Nutrition From Marz. Second Edition. Portland, OR. 1997
Rogers, L.L., et al. Quar. J of Studies on Alcohol 18:4: 581-7, 1957. Abstract: In a double blind cross-over trial 7 men and 3 women with long histories of excess drinking took 5 caps/day divided through day of lactose placebo or 200mg of glutamine. After 6 wks on L-glutamine 9 of 10 subjects, as well as friends and relatives, stated that the glutamine diminished the desire to drink and decreased anxiety and improved sleep. 2 or 3 subjects continued to do well after placebo substitution, but no subjects responded to placebo unless they had first responded to glutamine.
USDA: Composition of Foods. USDA Handbook #8. Washington DC, ARS, USDA, 1976-1986
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