There are many dietary supplements that do one thing well, such as support gains in lean body mass and strength like creatine monohydrate, or support restful sleep like melatonin. Glutamine is one of a few dietary supplements that can benefit the body in many different ways. We'll take a look at some of the benefits of this very important amino acid.
Glutamine is the most abundant amino acid in the body. It is a building block for almost everything in the body, and an energy source for many physiological processes. It is considered a "conditionally-essential amino acid." Under healthy, rested, unstressed circumstances, the body can produce enough glutamine to meet its daily needs. However, when the additional stress is added to the body, its need for glutamine may not be met by the body's production, and it becomes more critical to get glutamine through diet.
Research on glutamine has not always supported the need for its use through supplementation, especially when using research subjects that are healthy and under less stress. While the average healthy, sedentary individual may not benefit from the use of glutamine, most exercise enthusiasts understand the significance of this amino acid.
Glutamine and Immune Support
Generally, exercise is considered safe and healthy. However, exercise is still a stress to the body, and without supplying appropriate nutrients for recovery, successive exercise sessions can lead to overtraining and a suppression of the immune system. Most people have other stresses in their lives to contend with as well - financial stress, work stress, lack of sleep, sickness. All of these stresses can cause a decrease in the body's supply of glutamine which can suppress immune function. Endurance athletes may be more prone to glutamine deficiency from exercise than strength athletes, but both groups should pay attention to their recovery. Lack of rest and/or insufficient nutrition may lead to sickness. Avoiding immune system suppression may be an even greater benefit of glutamine use than its effect on muscle recovery. Being sidetracked with sickness can quickly throw an individual off their fitness program.
Glutamine and Digestive Health
Interestingly, the gastrointestinal (GI) tract is the body's greatest user of glutamine. It's actually used as an energy source by cells in the GI tract. It also supports the lining of the GI tract, which is important for preventing toxins and infections from entering the blood stream. Some believe a deficiency in glutamine can result in development of ulcerative colitis and Crohn's disease. More research is needed to show conclusive evidence of its ability to help reverse these conditions.
Regular users of nonsteroidal anti-inflammatory medications (NSAIDS) may develop inflammation or ulcers in the stomach. Glutamine has been shown to support healing of the stomach.
Glutamine and Exercise
Exercisers who do not allow sufficient time between workouts for recovery have a higher occurrence of depleted glutamine levels. It's common in these exercisers to have a higher occurrence of sickness and allergies. Because muscle tissue is the largest supplier of glutamine, not recovering between workouts may not allow sufficient time or nutrients to replenish glutamine stores. Lower glutamine levels are seen in endurance athletes and strength athletes alike, provided their training intensity is high enough. Low-intensity exercise does not usually lead to glutamine depletion. As an added bonus, glutamine can also support glycogen replenishment after exercise.
Other Benefits of Glutamine
Some additional ways glutamine may support the health of the body is to:
+ Help alleviate issues related to leaky gut syndrome
+ Support health of the liver
+ Help reduce muscle atrophy related to long-term anti-inflammatory steroids
+ Supply fuel to the heart
+ Support maintenance of lean body mass while dieting
+ Support healing of stomach ulcers
Glutamine is sometimes used to reduce muscle atrophy with various diseases, such as cancer as well.
Supplementing with Glutamine
The average American diet supplies 3.5-7.0 grams of glutamine per day. Glutamine can be found in beef, pork, poultry, milk, yogurt, ricotta cheese, cottage cheese, raw spinach, raw parsley and cabbage. The animal sources contain larger amounts because of their higher protein content. Whey protein is also an excellent supplemental source.
For sedentary individuals, the average daily amounts consumed are sufficient to meet the body's needs. For exercising individuals without significant health complications, 2-5 grams per day of additional supplemental glutamine is often recommended. Bodybuilders sometimes use dosages as high as 10 grams per day. Much higher doses, as high as 40 grams per day have been studied for therapeutic use, but those amounts are not necessary for generally healthy individuals.
As long as you are first taking in the basics for nutritional supplements, such as a high-quality multivitamin, fish oil, and getting enough protein, glutamine can be a great addition to a solid nutrition plan.
In health,
Tom Nikkola
References:
Miller A. Therapeutic Considerations of L-Glutamine: A Review of the Literature. Altern Med Rev 1999;5:239-248
Greenwell I. Glutamine: The Essential "Non-Essential" Amino Acid. LE Magazine. Sept. 1999
Walsh NP, Blannin AK, Robson PJ, Gleeson M. Glutamine, exercise and immune function. Links and possible mechanisms. Sports Med. 1998 Sep;26(3):177-91
University of Maryland Medical Center. Glutamine. http://www.umm.edu/altmed/articles/glutamine-000307.htm
Antonio J, Street C. Glutamine: a potentially useful supplement for athletes. Can J Appl Physiol. 1999 Feb;24(1):1-14
This article is not intended for the treatment or prevention of disease, nor as a substitute for medical treatment, nor as an alternative to medical advice. Use of recommendations in this and other articles is at the choice and risk of the reader.
