Glutamine: The benefits may surprise you!
Glutamine is a common supplement found in many supplement stores, gym bags, protein shakes and a plethora of other nutritional products. Yet, ironically it’s considered a non-essential amino acid…and in my opinion, the greatest benefits of glutamine rarely get recognized! This is a disservice to all of you, hence the goal of this article is not to change anyone’s opinion or sell you on a glutamine product. The goal is simply to teach you, to the best of my abilities, why glutamine is widely considered a staple in many training athletes supplement arsenal. As well as, why glutamine should have more universal appeal to those outside the “bodybuilding/fitness” arena.
What is Glutamine?
Glutamine is classified as a non-essential amino acid, since it can be readily synthesized by various tissues such as skeletal muscles, liver, and adipose tissue. glutamine is the most abundant single amino acid found in the bloodstream, which comprises 61% of the free intracellular amino acid pool (most abundant amino acid in skeletal muscle tissue), while Branched Chain Amino Acids (BCAA‘s) comprise 8.4% of the pool. Glutamine’s unique structure, containing two nitrogen side chains, consists of 19% nitrogen- making it the primary transporter of nitrogen into the muscle cells.
Over the years people begun to recognize the benefits of glutamine (each will be discussed further), such as:
1) Enhances the Immune System
2) Enhances glycogen storage
3) Improves Intestinal and Gastric health
4) Prevents Muscle Tissue breakdown (Catabolism)
5) Promotes Muscle Tissue growth and repair (Anabolism)
What Does Glutamine Do?
During exercise or other times of metabolic stress such as diet, severe injury, illness, etc. the demand for glutamine in your blood matrix (Plasma) markedly increases. For instance, various cells of the immune system such as lymphocytes and macrophages depend on glutamine as a primary fuel source, and thus the demand for glutamine increases when and immunological response is mounted. Macrophages and lymphocytes are the primary virus and bacteria fighter in your bloodstream. As glutamine travels through the body, the enterocytes of the small intestines are the largest consumers of glutamine accounting for about 40-50% of glutamine consumption. Also, glutamine is required for the synthesis of nucleotides. Thus, a sufficient supply of glutamine is particularly important for rapidly dividing cells such as enterocytes and the immune cells. Therefore, the synthesis of glutamine may be insufficient to meet the physiological demand during times of severe metabolic stress when the amount of free glutamine is rapidly depleted. Therefore, it may be beneficial for people who continuously place themselves in infectious areas or commonly get sick, to supplement with glutamine to aide virus and/or bacteria fighting cells.
Glutamine supplementation may also promote nitrogen retention (a positive nitrogen balance) and prevent the loss of muscle protein. A decreased ratio of testosterone to cortisol is believed to be directly responsible for losses in muscle mass since cortisol promotes the synthesis of glutamine. By maintaining intracellular concentrations of glutamine within the skeletal muscles, the synthesis of glutamine may prevent the loss of intracellular nitrogen.
Therefore, it may be beneficial for people who continuously place themselves through strenuous workouts to supplement with glutamine to aide when glutamine stores are depleted. Furthermore, by enhancing plasma concentrations of glutamine, the demand for free form glutamine by other tissues and cells (i.e., small intestines and immune cells) is attenuated and thus the release of glutamine from muscle tissues is reduced.
Why Does Your Body Need Glutamine?
To fully understand why glutamine is beneficial to the body, we must continue this biochemistry lesson. The body uses glutamine to shuttle ammonia around in the body, so blood levels of glutamine try to maintain constant. Glutamine is craved by the digestive tract and the immune system as fuel. Most people eat more than enough protein from the supermarket, but they do not get enough glutamine through the digestion of meats and other proteins. Under certain pathological circumstances the body’s tissues need more glutamine than the overall amount supplied by the diet and natural synthesis such as during a strenuous workout.
During catabolic stress, for instance, intracellular glutamine levels can drop more than 50% and plasma concentrations can fall by 30%. It’s under these circumstances that supplemental glutamine becomes necessary.
Skeletal muscle contains the greatest intracellular concentrations of glutamine, comprising up to 60% of total body glutamine stores, and is considered the primary storage depot of glutamine, and thus the primary exporter of glutamine to other tissues. In times of metabolic stress, glutamine is released into circulation, where it is transported to the tissue(s) in need. Intracellular skeletal muscle glutamine concentration is affected by various assaults including injury, sepsis, prolonged stress, and starvation. Besides skeletal muscle, the lungs are the next largest producer of glutamine.
Glutamine is especially useful post workout when nutrients are at a low until recovery. In this condition research shows glutamine levels are significantly reduced, taking up to one month (in extreme cases) to return to baseline. In athletes, glutamine has been used as a marker to indicate overtraining. This fall in glutamine is catabolic to muscle tissue. In a catabolic state, glutamine is the first amino acid used to correct that deficiency. Glutamine drives protein into the muscle cells where it is synthesized for growth This means that additional glutamine is necessary during periods of stress, resulting in bigger, stronger muscle cells.
In a recent study of glutamine’s role enhancing the immune system, glutamine demonstrated that increased levels of glutamine leads to greater amounts of virus and infection fighting cells, T and B Lymphocytes. Cells of the immune system including the macrophages and lymphocytes depend on glutamine as a primary fuel source. In addition, it has been hypothesized that a high rate of glutamine consumption by these rapidly proliferation cells is required for sufficient nucleotide synthesis.
Research indicates that low levels of glutamine within the body may result in the increased susceptibility to infections and illness due to a suppressed immune system. The ability to reproduce and the activity of immune cells in vitro have reportedly been suppressed in trials lacking glutamine. Tests also demonstrated that the increased rate of infection and illness (particularly infections of the upper respiratory tract) has been reported among athletes participating in intense, long duration sports (i.e., marathon racing).
It has been suggested that a decline in plasma glutamine concentrations may be one of the factors responsible for this increased rate of illness. Specifically, the activity of natural killer cells, a reduced number and proliferate ability of lymphocytes, and a reduced ratio of T-helper to T-suppressor cells may be the result of prolonged, exhaustive exercise.
Glutamine as a GDA (Glucose Disposal Agent)
In another study of glutamine’s role on glucose and glycogen formation, the importance of glutamine was also emphasized. The human carbon based skeleton of glutamine can serve as a gluconeogenic precursor and may regulate gluconeogenesis, which is basically the production of glycogen, independently of the insulin/glucagon ratios. Because glutamine may serve as a precursor to glucose independently of glucagon regulation, glutamine supplementation may also enhance glycogenolysis and thus increase muscle glycogen stores even when insulin levels are low. So basically glutamine helps regulate glycogen in your body when levels are low and may even increase them, which would result in better performance and growth.
Use of Glutamine
Glutamine and L-Glutamine can be purchased in powder or capsule form. Glutamine containing products are protein shakes, protein powders and protein drinks. Additional glutamine can be added to protein powders and shakes. However, glutamine is relatively unstable in solution, and thus glutamine powders must be consumed shortly after being mixed into solution.
Glutamine Side Effects
It is completely safe. There are no known side effects.
Hopefully this article has opened you up to the topic of glutamine supplementation. Supplementing with glutamine can result in measurable gains in strength, muscularity, and immune function. Taking glutamine before and during a workout will increase performance and delay fatigue. This amino acid is needed for the maintenance of muscle tissue during physical stress and intense exercise and plays a crucial role in the fight against sickness. From the perspective of athletes, glutamine functions as an anabolic/anti-catabolic agent, which allows the body to burn fat and not muscle. Therefore, glutamine is crucial in your quest to achieve Ultimate Human Performance!!