Glutamine, Worth the $$?

[NewlyDesigned]

Well I was just wondering if Glutamine was worth the money. I go to school right now and only have a part time job so any money i spend has to be spent wisely lol. Right now I am taking Creatine Mono and some Whey Protein and was wondering if the Glutamine would really make that much of a difference.If you think you knwo of something cheap that works could you please post the name and where ya got it. Also I was wondering if any of you knew of a store on the internet with cheap prices for suppliments and good products in Canada.

Thanks a lot to anyone who helps out, I appreciate it

[mario_ps2]

Of what I have read on this forums....Glutamine is basically a piece of garbage and a waste of money....

[RuhlFreak55]

Glutamine seriously? it's a building block one of the most important suppments. It's not even that expensive. Glutamine is the most plentiful amino acid in the body. I take between 10 and 15 grams a day.

[Giantz11]

Glutamine seriously? it's a building block one of the most important suppments. It's not even that expensive. Glutamine is the most plentiful amino acid in the body. I take between 10 and 15 grams a day.

Exactly, so why on earth supplement with it???

If you were getting really sick after working cause of depressed imune function then maybe take it IV. Other than that its worthless, it's also speculated that about 90% of orally ingested glutamine is rendered usless in the gut upon digestion.

[RuhlFreak55]

Exactly, so why on earth supplement with it???

If you were getting really sick after working cause of depressed imune function then maybe take it IV. Other than that its worthless, it's also speculated that about 90% of orally ingested glutamine is rendered usless in the gut upon digestion.

I"d like to know where that stat came from.....and i forgot to mentioni it's also the most important amino acid for building muscle

[Giantz11]

I"d like to know where that stat came from.....and i forgot to mentioni it's also the most important amino acid for building muscle

Really it is? You mean Leucine isn't?

[Giantz11]

Leucine regulates translation initiation of protein synthesis in skeletal muscle after exercise.

Norton LE, Layman DK.

Division of Nutritional Sciences, Department of Food Science and Human Nutrition, University of Illinois at Urbana-Champaign, Urbana, IL 61801.

High-performance physical activity and postexercise recovery lead to significant changes in amino acid and protein metabolism in skeletal muscle. Central to these changes is an increase in the metabolism of the BCAA leucine. During exercise, muscle protein synthesis decreases together with a net increase in protein degradation and stimulation of BCAA oxidation. The decrease in protein synthesis is associated with inhibition of translation initiation factors 4E and 4G and ribosomal protein S6 under regulatory controls of intracellular insulin sign****g and leucine concentrations. BCAA oxidation increases through activation of the branched-chain alpha-keto acid dehydrogenase (BCKDH). BCKDH activity increases with exercise, reducing plasma and intracellular leucine concentrations. After exercise, recovery of muscle protein synthesis requires dietary protein or BCAA to increase tissue levels of leucine in order to release the inhibition of the initiation factor 4 complex through activation of the protein kinase mammalian target of rapamycin (mTOR). Leucine's effect on mTOR is synergistic with insulin via the phosphoinositol 3-kinase sign****g pathway. Together, insulin and leucine allow skeletal muscle to coordinate protein synthesis with physiological state and dietary intake.

[Giantz11]

Essential amino acids and muscle protein recovery from resistance exercise.

Borsheim E, Tipton KD, Wolf SE, Wolfe RR.

Metabolism Unit, Department of Surgery, Shriners Hospital for Children/Galveston, University of Texas Medical Branch, Galveston, Texas 77550, USA.

This study tests the hypothesis that a dose of 6 g of orally administered essential amino acids (EAAs) stimulates net muscle protein balance in healthy volunteers when consumed 1 and 2 h after resistance exercise. Subjects received a primed constant infusion of L-[(2)H(5)]phenylalanine and L-[1-(13)C]leucine. Samples from femoral artery and vein and biopsies from vastus lateralis were obtained. Arterial EAA concentrations increased severalfold after drinks. Net muscle protein balance (NB) increased proportionally more than arterial AA concentrations in response to drinks, and it returned rapidly to basal values when AA concentrations decreased. Area under the curve for net phenylalanine uptake above basal value was similar for the first hour after each drink (67 +/- 17 vs. 77 +/- 20 mg/leg, respectively). Because the NB response was double the response to two doses of a mixture of 3 g of EAA + 3 g of nonessential AA (NEAA) (14), we conclude that NEAA are not necessary for stimulation of NB and that there is a dose-dependent effect of EAA ingestion on muscle protein synthesis.

[Giantz11]

Muscle glutamine depletion in the intensive care unit

Gianni Biolo, , Francesca Zorat, Raffaella Antonione and Beniamino Ciocchi

Department of Clinical, Morphological and Technological Sciences, University of Trieste, Trieste, Italy

Received 28 October 2004; revised 3 May 2005; accepted 4 May 2005. Available online 31 May 2005.




Abstract
Glutamine is primarily synthesized in skeletal muscle and enables transfer of nitrogen to splanchnic tissues, kidneys and immune system. Discrepancy between increasing rates of glutamine utilization at whole body level and relative impairment of de novo synthesis in skeletal muscle leads to systemic glutamine deficiency and characterizes critical illness. Glutamine depletion at whole body level may contribute to gut, liver and immune system disfunctions, whereas its intramuscular deficiency may directly contribute to lean body mass loss. Severe intramuscular glutamine depletion also develops because of outward transport system upregulation, which is not counteracted by increased de novo synthesis. The negative impact of systemic glutamine depletion on critically ill patients is suggested both by the association between a lower plasma glutamine concentration and poor outcome and by a clear clinical benefit after glutamine supplementation. Enteral glutamine administration preferentially increases glutamine disposal in splanchnic tissues, whereas parenteral supplementation provides glutamine to the whole organism. Nonetheless, systemic administration was ineffective in preventing muscle depletion, due to a relative inability of skeletal muscle to seize glutamine from the bloodstream. Intramuscular glutamine depletion could be potentially counteracted by promoting de novo glutamine synthesis with pharmacological or nutritional interventions.

[RuhlFreak55]

* This is the most abundant amino acid in muscle tissue. Scientific studies seem to support the theory that glutamine supplementation may be important to maximizing muscle growth. In one recent study, it was shown that just a two-gram dose of glutamine caused a rather significant increase in growth-hormone levels.


Leucine.......

* Metabolized in muscle tissue
* Promotes he****g of skin and broken bones.
* Lowers elevated blood sugar levels
* Should always be in well balanced proportion with L-V****e and L-Isoleucine.

I think i could be right........

[Giantz11]

Glutamine accounts for about 8–12% of total amino acid content of dietary proteins. The total oral intake and absorption of the free amino acid is, therefore, about 10 g per day, but this represents only 12% of the whole body glutamine appearance (Fig. 1). In addition, systemic availability of enteral glutamine is further reduced by first pass splanchnic metabolism. Studies involving oral ingestion of stable isotope-labelled glutamine indicate that 50–70% of enterally administered glutamine is taken up during first pass by splanchnic organs (gut and liver) (Matthews, Marano, & Campbell, 1993) where it is largely oxidized (Haisch, Fukagawa, & Matthews, 2000). Thus, kinetic data indicate that whole body glutamine availability largely depends on the rate of endogenous synthesis in skeletal muscle.

[RuhlFreak55]

ok obviously there's evidence either way

[Giantz11]

* This is the most abundant amino acid in muscle tissue. Scientific studies seem to support the theory that glutamine supplementation may be important to maximizing muscle growth. In one recent study, it was shown that just a two-gram dose of glutamine caused a rather significant increase in growth-hormone levels.


Leucine.......

* Metabolized in muscle tissue
* Promotes he****g of skin and broken bones.
* Lowers elevated blood sugar levels
* Should always be in well balanced proportion with L-V****e and L-Isoleucine.

I think i could be right........

I hope that's a joke bro, cause if its not you just plain don't know what the hell you're talking about.

[Giantz11]

ok obviously there's evidence either way

No, there's no evidence for Glutamine what so ever, that's the point. Its worthless, let it go.

[Giantz11]

Translational control of protein synthesis: implications for understanding changes in skeletal muscle mass.

Jefferson LS, Kimball SR.

Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey 17033, USA.

Gain or loss of skeletal muscle mass is due largely to the establishment of an imbalance between rates of protein synthesis and degradation. A key determinant of the rate of protein synthesis is translation initiation, a process regulated in part through binding of initiator methionyl-tRNA (met-tRNAi) and messenger RNA (mRNA) to a 40S ribosomal subunit. Either the met-tRNAi or mRNA binding step can become limiting for protein synthesis. Furthermore, the mRNA binding step can modulate translation of specific mRNAs with or without changes in the overall rate of protein synthesis. This report highlights molecular mechanisms involved in mediating control of the mRNA binding step in translation initiation. Particular attention is given to the effect of exercise on this step and to how the branched-chain amino acid leucine stimulates muscle protein synthesis after exercise. Potential mechanisms for exercise-induced increase in muscle mass are discussed.

[Giantz11]

Should I Spend my Hard-Earned Money on Glutamine or Hookers?

By John Berardi

Q: In a recent ***** article, glutamine was described as pretty much worthless if you're already taking care of protein and post-workout protein/carb/amino needs. What's your opinion? Is glutamine overrated?

A: Well, for starters, glutamine is the most abundant free amino acid…
Aww hell; I'm not going start my response off with the standard opening line that just about everyone uses to indirectly affix grandiose importance to this amino acid! Sure, it's conditionally essential (meaning that although it's not absolutely necessary in the diet, our requirements for glutamine can exceed our production of it in certain conditions).

Yes, it makes up 2/3 of the muscle's free amino acid pool (which is a pretty damn small part of the muscle's total amino acid content anyway) and sure, glutamine has been shown to have some pretty amazing benefits in wasting conditions, postoperative patients, and in TPN (total parenteral nutrition).

But as bodybuilding/fitness writers, it's about time we put aside this useless trivia and discuss the utility of glutamine supplementation for athletes, weight lifters, etc. A few years ago there were no data and therefore we could speculate all we wanted about the theoretical potential of glutamine supplementation. But nowadays, we've got the data and the data demonstrate that our theories may have been wrong.

To this end, I applaud my good friend David Barr on his excellent articles (Glutamine — Destroying the Dogma Part I and Part II) that revealed that despite all the conjecture about how glutamine supplementation may help increase muscle mass, muscle strength, and prevent overtraining, each and every research investigation examining the effects of glutamine supplementation on exercise performance, body composition, and protein degradation has shown that it offers no benefit. Because of the great job that Dave did in his literature review, I certainly don't have to provide a reference list — they're all right there at the end of his article.

To reiterate a few of the key points that Dave brought up in his article and that I brought up at the SWIS seminar:

• A high protein diet provides a big whack of glutamine as it is. In fact, if you follow standard bodybuilding protein recommendations, about 10% of your total dietary protein intake is composed of glutamine (milk proteins are composed of somewhere between 3 — 10% glutamine while meat is composed of about 15% glutamine). This means that a high protein diet (400g/day) already provides me with about 40g of glutamine.

• While the theorists still cling to the idea that since glutamine helps clinical stress, it might help with exercise stress, it’s important to note that exercise stress has got nothin’ on surgery, cancer, sepsis, burns, etc. For example, when compared with downhill running or weight lifting, urinary nitrogen loss is 15x (1400%) greater in minor surgery, 25x (2400%) greater in major surgery, and 33x (3200%) greater in sepsis. When it comes to the immune response, it’s about 9x (800%) greater with surgery. When it comes to metabolic increase, it’s 7x (600%) greater with burn injury, and when it comes to creatine kinase release; it’s about 2x (100%) greater with surgery. As I said, exercise has got nothin’ on real, clinical stress. It’s like trying to compare the damage inflicted by a peashooter and that inflicted by a rocket launcher.

• The major studies examining glutamine supplementation in otherwise healthy weightlifters have shown no effect. In the study by Candow et al (2001), 0.9g of supplemental glutamine/kg/day had no impact on muscle performance, body composition, and protein degradation. Folks, that's 90g per day for some lifters.

• The majority of the studies using glutamine supplementation in endurance athletes have shown little to no measurable benefit on performance or immune function.

• And with respect to glycogen replenishment in endurance athletes, it's interesting to note that the first study that looked at glycogen resynthesis using glutamine missed a couple of things. Basically, the study showed that after a few glycogen depleting hours of cycling at a high percentage of VO2 max interspersed with very intense cycle sprints that were supramaximal, a drink containing 8g of glutamine replenished glycogen to the same extent as a drink containing 61g of carbohydrate.

The problem was that during the recovery period, a constant IV infusion of labeled glucose was given (i.e., a little bit of glucose was given to both groups by IV infusion). While this isn't too big of a deal on its own since the infusion only provided a couple of grams of glucose, the other problem is that during glycogen depleting exercise, a lot of alanine, lactate, and other gluconeogenic precursors are released from the muscle.

What this means is that there's a good amount of glucose that will be formed after such exercise, glucose that will be made in the liver from the gluconeogenic precursors and that will travel to the muscle to replenish glycogen. Therefore, without a placebo group that receives no calories, carbohydrates, or glutamine, we have no idea of knowing whether or not the placebo would have generated the same amount of glycogen replenishment as the glutamine group or the glutamine plus carbohydrate group. To say it another way, perhaps there's a normal glycogen replenishment curve that was unaffected by any of the treatments.

• And finally, with respect to the claims that glutamine might increase cell swelling/volume (something I once believed was a reality), we decided to test this theory out in our lab using multifrequency bioelectric impedance analysis as well as magnetic resonance spectroscopy. The pilot data that's kicking around has demonstrated that glutamine supplementation has no effect on total body water, intracellular fluid volumes, or extracellular fluid volumes (as measured by mBIA) and has no effect on muscle volume (as measured by nMRS).

Therefore, at the present time, I think it's safe to conclude that glutamine supplementation probably offers little to no benefit with respect to athletic performance or body composition when given to well-fed, healthy athletes. But I don't want to totally burst anyone's little glutamine bubble. After all, I'm not saying that glutamine supplementation is totally worthless. As Dave Barr pointed out in his article, there may be some circumstances in which glutamine supplementation is of benefit. Here are some of them:

• Steroid users who are improperly coming off a cycle might need some. When coming off a steroid cycle, blood Testosterone concentrations are dismally low while cortisol levels become quite elevated. If said steroid user continues training (which he/she must to try to preserve their muscle mass), the catabolic stimulation might be significant. It still doesn't approach clinical catabolism but it may just become bad enough that some extra glutamine might help. This is just a guess, however.

• When trying to get really lean, many bodybuilders restrict energy intake and increase exercise volume and might need some glutamine. This type of energy deficit may signal the body to begin using protein as an energy source, cutting into valuable muscle resources. In addition this catabolic stimulus will be compounded by the exercise stress and may lead to excess catabolism. Perhaps glutamine may help out in these scenarios. Again, a guess.

• In elite endurance athletes training intensely 2 or 3 times in a given day, I might prescribe some. Although I rarely recommend glutamine to my clients, my elite cross country skiers are encouraged to take it mostly during their trips to altitude camp and for glacier training. These athletes train 2-3 times per day for a week or two at a time while living in tents on a glacier at altitude. Add on the fact that nutrition on such excursions is bare bones, so that's some stress that glutamine might help with.

• When injured and trying to prevent wasting or facilitate wound/soft tissue injury, take some. Williams et al (2002) demonstrated that daily supplementation with 3g of HMB, 14g of glutamine, and 14g of arginine can lead to increased wound he****g.

So when all is said and done, I pretty much agree with Dave's appraisal of the value of glutamine supplementation for well-fed weightlifters and bodybuilders. Considering how much protein most bodybuilders consume, additional glutamine supplementation are probably worthless. However, like any other question, there isn't a black and white answer. There do remain a few situations, as discussed above, that glutamine might be a supplement to consider. Personally, I only prescribe it to my skiers during altitude and glacier training, to steroid users coming "off," to bodybuilders during the last few weeks of competition dieting, and to people who are injured and trying hard to recover. And, of course, to those with legitimate wasting conditions. If you don't fall into any of these categories, spend your money on more groceries.

Toxic Schmoxic

Q: Everyone at the forefront of nutrition these days in recommending fish oil; however, they all quickly add that it's "toxic." What the heck is going on here?! Should I take fish oil or is the mercury going to kill me? Along those same lines, should I limit how much tuna I eat?

A: I've got a secret to tell you… Everything's "toxic!" That's right. Everything!
I'm not allowed to eat lean meat because it contains trace amounts of hormones; I'm not allowed to eat fish because it contains a small amount of mercury (we're talking about fractions of parts per million units, or 0.0000001 units, people!); I'm not allowed to eat fruits and vegetables because they are covered in small amounts of pesticides; I'm not allowed to have sex because the condoms I'm using may deliver a micro dose of environmental estrogens; I'm not allowed to cook my food because that renders the food indigestible; I'm not allowed to own a microwave because it sends off electromagnetic energy that will give me cancer in addition to destroying my food; I'm not allowed to drink tap water, distilled water, cold water, or even filtered water from non-glass containers because I'll be getting too much chloride, fluoride, the wrong ionization, impaired digestion, or chemicals leached from the plastic containers; and I'm not even allowed to type this freakin' article because my computer monitor is sending off both electromagnetic fields as well as toxic chemicals into the air, causing a slow erosion of my health.

I might as well go back to bed. If I stay there all day, I'll be safe — wont I?
I've gotta be honest with you. I really hate the way that the health paranoiacs brandish the word toxic as if it was a loaded gun. If I had a nickel for every person that told me that fish oil or tuna or one of a host of other foodstuffs was toxic, I'd be a wealthy man. After all, what exactly are those fear mongers saying when they use the word toxic? To me, it's nothing more than waving their magic paranoid wands over something and making it, from that day forward, synonymous with "bad." When they say fish oil is toxic, they're telling us nothing other than their opinion that it's bad. So rather than saying fish oil is bad, how about discussing what those toxins are and perhaps demystifying them?

Since fish are part of the food chain, they, like many other foods, are subject to contamination. To this end, the Canadian Food Inspection Agency, and agencies like it across the world (i.e. Britain's Food Standards Agency) take measures to quantify the level of contaminants, or "toxins" and determine whether or not the levels of these chemicals are enough to cause any serious health concern.

Remember, pretty much everything, especially every food, nowadays, has been linked to some type of cancer or malady. So don't get all worked up when I tell you that fish can contain some contaminants. After all, even if you don't get those contaminants directly from the fish, you'll be getting them from the livestock that eat the fish (fish meal and fish oil are very popular livestock feeds), or diluted in your water supply, or from the fruits and vegetables you eat. Yes, the state of affairs of our environment truly sucks. It sure sucks that our water, our air, and our food is all polluted. And I think it's important to do our own part in seeing that this state of affairs improves. But in the meantime, life must go on and we must make choices as to how to live it.

So now that we know everything we eat has some contaminants and could therefore technically be described as "toxic," and we know that this is because we have allowed our chemicals to muck up our environment, let's clarify that this description of "toxic" means that the foods contain some substances that can cause harm if consumed in high enough concentrations. With that said, let's discuss which toxins are found in fish and whether they're found in high enough concentrations to be of concern.
The contaminants usually associated with fish are dioxins and furans, PCB's, DDT, and mercury. To give you some clue of what these compounds are, here's a quick synopsis:

• Dioxins and furans are components in a group of substances (polychlorinated planar aromatic structures) which have similar physical and chemical properties and consist of 75 polychlorinated dibenzo-para-dioxins (PCDDs) and 135 polychlorinated dibenzofurans (PCDFs). Seventeen members of this group have been studied extensively and are considered "toxic".

• PCBs are also persistent pollutants, some of which resemble the chemical structure of "dioxin-like" compounds. PCBs differ from dioxins and furans in that they are manufactured for transformers, insulators, capacitors etc., while dioxins and furans are produced unintentionally, as unwanted by-products from various combustion and industrial processes and from natural events like forest fires and volcanic eruptions.

• DDT is a colorless chemical pesticide, dichlorodiphenyltrichloroethane, used to eradicate disease-carrying and crop-eating insects. Unfortunately, this chemical has been linked to the death of many other animal species, to reproductive abnormalities in wildlife, and even cancer in humans.

• Methyl mercury is a highly toxic substance; there are a number of adverse health effects associated with methyl mercury exposure. Most extensive are the data for neurotoxicity, particularly in developing organisms.
Now that's an ugly picture isn't it? Knowing that these substances are found in fish does make me a bit hesitant. But we've gotta put things into perspective here. Most of the studies I've seen indicate that many of the fish oils available on the market today as well as many of the fish meal products contain only small amounts of these 4 toxins, amounts well below the limits at which health concerns might arise. Now remember, just because a food might have some toxins in it, that doesn't mean that it will cause health problems. Just like most drugs have a minimum effective dose, so do toxins. We all know that 1mg of caffeine will do nothing to promote concentration or alertness. But take 200mg and all of a sudden, things start to happen.

Since you also asked about tuna, I'll address that as well. Yes, tuna contains some mercury. But the levels of mercury contained in tuna are about 1/3 as low as those in fish considered to present a health risk. In addition, canned tuna has much less mercury than fresh tuna, so this bodybuilding staple is probably just about as safe as the next food.
While it's easy to understand why the health paranoia proponents are cautioning us against this toxic fish or fish oil, we can't let them take the focus off what's important here. Thousands of studies have been done using fish oil (of all concentrations and "purities") and in each study the benefits of the fish oil have manifested in amazing ways. Talk about a panacea for our culture's syndrome x problems! And in the face of this overwhelming evidence in favor of fish oil, there's been very little reported in the way of negative effects.

But even if the research isn't enough to convince you, how about checking out the health histories of the people with the highest level of deep ocean fish consumption? You won't find a dramatically high incidence of "toxicity." In fact, these people are far healthier than North Americans are.
At this year's SWIS symposium, everyone recommended fish oil but most of these people also suggested that fish oil was toxic. Interesting that in the face of all of this toxicity, the studies have shown overwhelming benefits anyway, such that the experts are still recommending them.

Regardless, one thing I did take away from the SWIS symposium, something I've been championing for a long time now, was that you should be getting concentrated forms of EPA/DHA — especially if you're taking a whole lot of it. For example, Barry Sears recommended "pharmaceutical grade" fish oil, which is defined as containing > 60% EPA+DHA, isn't a bad idea. I'm also told that Biotest is coming out with a fish oil that will match or surpass that percentage of EPA +DHA.

In the end, I've heard all the arguments for and against using fish oil and my conclusion, at this point, is that even if there is potential toxicity (mercury or anything else), the benefits FAR outweigh the risks. So when health experts suggest avoiding fish oil, I think they're doing people a disservice. By creating a big toxin scare they're discouraging the use of the ultra-health promoting oils. They're "muddying the waters," so to speak, and people, in the absence of an expert consensus, do nothing proactive to take control of their health.

[NewlyDesigned]

Some great stuff there guys but that only two opinions, anymore people willing to share what they think would be great

[SVTMuscle*]

well your not gonna be having many other ppl post such good studies and opions so appreciate what you got! if you cant determine what to do with it now, then dont bother getting it

[210-6foot]

Glutamine, I know this guy that takes it everyday. He's a pretty huge dude... 270 pounds. He claims he dosen't take steroids, idk. He said he takes roughly around 540 grams of protein a day. I don't think it's great, but I was just making a comment.

[Papi93]

Of what I have read on this forums....Glutamine is basically a piece of garbage and a waste of money....

Agreed. I've used it before and I will stand by Giantz11 on this subject.

[Natron-Killer20]

i dont know much and i know glutamine is a must

[Giantz11]

i dont know much and i know glutamine is a must

That's quite clear now, thanks.

[Natron-Killer20]

[Act of God]

i've never noticed anything either way with it. I would tend to assume its not that important

[gmmvp42]

my 2cents,
took 10 grams with protein drink, w/o an hour+ later, felt great muscle pump, got stoked, went home, read that less than 10% of glutamine makes it thru your gut, repeated drink b4 next w/o, didn't feel agro pump, tried it again, no super pump, finished bottle, no more miracle pump. never used it again. This was probably 12 years ago ,most likely read the 10% thing from either Dan Duchaine/Bill Phillips/Muscle Media or ISSA's training material, somebody in that circle, I didn't have the internet then. My arms did feel huge(for me) that first time though....

[sooners04]

Just another view on this controversy.

L-Glutamine

TRADE NAMES
Glutamine Fuel Powder (Twinlab), Glutamine Fuel Mega (Twinlab), Glutamine Express (Genetic Evolutionary Nutrition), L-Glutamine Power (Champion Nutrition), Earthlink Science Glutamine Chews Chocolate (Amerifit).

DESCRIPTION
L-glutamine is a protein amino acid found in proteins of all life forms. It is classified as a semi-essential or conditionally essential amino acid. This means that under normal circumstances the body can synthesize sufficient L-glutamine to meet physiological demands. However, there are conditions where the body cannot do so. Recently, L-glutamine has come to be regarded as one of the most important of the amino acids when the body is subjected to such metabolic stress situations as trauma (including surgical trauma), cancer, sepsis and burns. Under such conditions, L-glutamine becomes an essential amino acid, and it is therefore very important to ensure adequate intakes of the amino acid in order to meet the increased physiological demands created by these situations.

L-glutamine is the most abundant amino acid in the body, and plasma glutamine levels are the highest of any amino acid. L-glutamine is predominantly synthesized and stored in skeletal muscle. The amino acid L-glutamate is metabolized to L-glutamine in a reaction catalyzed by the enzyme glutamine synthase, a reaction which, in addition to L-glutamate, requires ammonia, ATP and magnesium.

L-glutamine is a very versatile amino acid and participates in many reactions in the body. It is important in the regulation of acid-base balance. L-glutamine allows the kidneys to excrete an acid load, protecting the body against acidosis. This is accomplished by the production of ammonia, which binds hydrogen ions, to produce ammonium cations that are excreted in the urine along with chloride anions. Bicarbonate ions are simultaneously released into the bloodstream. L-glutamine helps protect the body against ammonia toxicity by transporting ammonia, in the form of L-glutamine's amide group, from peripheral tissues to visceral organs, where it can be excreted as ammonium by the kidneys or converted to urea by the liver.

The amide group can also participate in other metabolic activities, as can the amino group of L-glutamine. L-glutamine serves as the most important nitrogen shuttle, supplying nitrogen for metabolic purposes (from glutamine-producing tissues, such as skeletal muscle) to glutamine-consuming tissues.

L-glutamine participates in the formation of purine and pyrimidine nucleotides, amino sugars (such as glucosamine), L-glutamate and other amino acids, nicotinamide adenine dinucleotide and glutathione. It also participates in protein synthesis, energy production and, if necessary, the production of D-glucose and glycogen. Importantly, L-glutamine can serve as the primary respiratory substrate for the production of energy in enterocytes and lymphocytes. L-glutamine is considered an immunonutrient, and supplemental L-glutamine is used in medical foods for such stress situations as trauma, cancer, infections and burns.

The typical dietary intake of L-glutamine is 5 to 10 grams daily. Most dietary L-glutamine comes from animal and plant proteins. Small amounts of free L-glutamine are found in vegetable juices and fermented foods, such as miso and yogurt. L-glutamine is the amide of L-glutamic acid. Its molecular formula is C5H10N2O3, and its molecular weight is 146.15 daltons. The structural formula is:




L-glutamine


L-glutamine is also known as 2-aminoglutaramic acid, levoglutamide, (S)-2, 5-diamino-5-oxopentaenoic acid and glutamic acid 5-amide. Its one-letter abbreviation is Q, and it is also abbreviated as Gln. The terms L-glutamine and glutamine are used interchangeably. D-glutamine, the stereoisomer of L-glutamine, does not have, as far as is known, biological activity. L-glutamine is not very soluble in water, and aqueous solutions are unstable at temperatures of 22 to 24 degrees Celsius. For these reasons, the more soluble and more stable glutamine dipeptides are used as delivery forms of L-glutamine in total parenteral nutrition (TPN) solutions. See Glutamine Peptides.

ACTIONS AND PHARMACOLOGY
ACTIONS
Supplemental L-glutamine may have immunomodulatory, anticatabolic/anabolic and gastrointestinal mucosal-protective actions. It may also have antioxidant activity.

MECHANISM OF ACTION
Supplemental L-glutamine's possible immunomodulatory role may be accounted for in a number of ways. L-glutamine appears to play a major role in protecting the integrity of the gastrointestinal tract and, in particular, the large intestine. During catabolic states, the integrity of the intestinal mucosa may be compromised with consequent increased intestinal permeability and translocation of Gram-negative bacteria from the large intestine into the body. The demand for L-glutamine by the intestine, as well as by cells such as lymphocytes, appears to be much greater than that supplied by skeletal muscle, the major storage tissue for L-glutamine. L-glutamine is the preferred respiratory fuel for enterocytes, colonocytes and lymphocytes. Therefore, supplying supplemental L-glutamine under these conditions may do a number of things. For one, it may reverse the catabolic state by sparing skeletal muscle L-glutamine. It also may inhibit translocation of Gram-negative bacteria from the large intestine. L-glutamine helps maintain secretory IgA, which functions primarily by preventing the attachment of bacteria to mucosal cells.

L-glutamine appears to be required to support the proliferation of mitogen-stimulated lymphocytes, as well as the production of interleukin-2 (IL-2) and interferon-gamma (IFN-gamma). It is also required for the maintenance of lymphokine-activated killer cells (LAK). L-glutamine can enhance phagocytosis by neutrophils and monocytes. It can lead to an increased synthesis of glutathione in the intestine, which may also play a role in maintaining the integrity of the intestinal mucosa by ameliorating oxidative stress.

The exact mechanism of the possible immunomodulatory action of supplemental L-glutamine, however, remains unclear. It is conceivable that the major effect of L-glutamine occurs at the level of the intestine. Perhaps enteral L-glutamine acts directly on intestine-associated lymphoid tissue and stimulates overall immune function by that mechanism, without passing beyond the splanchnic bed.

The anticatabolic/anabolic activity of supplemental L-glutamine can be explained by its effect in sparing skeletal muscle L-glutamine stores.

PHARMACOKINETICS
Following ingestion, L-glutamine is absorbed from the lumen of the small intestine into the enterocytes. Absorption is efficient and occurs by an active transport mechanism. Some metabolism of the amino acid takes place in the enterocytes. L-glutamine that is not metabolized in the enterocytes enters the portal circulation from whence it is transported to the liver, where again some portion of the amino acid is metabolized. L-glutamine not metabolized in the liver enters the systemic circulation, where it is distributed to the various tissues of the body. L-glutamine participates in various metabolic activities, including the formation of L-glutamate catalyzed by the enzyme glutaminase. It also participates in the synthesis of proteins, glutathione, pyrimidine and purine nucleotides and amino sugars. The transport of L-glutamine into cells is via an active process. L-glutamine is eliminated by glomerular filtration and is almost completely reabsorbed by the renal tables.

INDICATIONS AND USAGE
Glutamine has been shown to be beneficial when administered in the form of glutamine peptides via TPN in some patients with varying forms of catabolic stress, e.g., some cancer, transplantation, intensive-care, surgical and immune-suppressed patients. Benefits from enteral glutamine supplementation are generally less pronounced, but preliminary significant results have been reported with the use of oral glutamine in very-low-birth-weight infants and in some major trauma patients in whom glutamine seems to strengthen immunity, particularly in the gastrointestinal tract. Glutamine may help protect against some of the side effects of cancer chemotherapy and radiotherapy.

There is little concurring evidence that glutamine is an effective ergogenic aid, but there is some suggestion that it might help protect against exercise-induced immune impairment. Some dated research suggesting that glutamine might help curb alcohol craving has not been followed up. Claims that it helps prevent neurodegenerative disorders or that it modulates mood have not been substantiated.

RESEARCH SUMMARY
Several well-designed studies have demonstrated that the addition of glutamine to TPN helps decrease intestinal permeability and mucosal and villous atrophy in the small intestine. Inhibition of intestinal permeability is believed to decrease microbial translocation and thus reduce infective opportunities in the gut. Increased intestinal permeability has been associated with a number of traumas, illnesses and some surgeries.

Studies have shown worthwhile reductions in length of hospital stay attributed to glutamine-supplemented TPN in bone-marrow transplantation patients and in those who had resection for colon or rectal cancer. In another study, mortality was significantly better in intensive-care patients who received TPN supplemented with glutamine than in those whose TPN did not include glutamine.

In addition, glutamine in TPN has been credited with improving nutritional status in some critically ill patients, including cancer patients. And it appears to allow for more aggressive radiotherapy and chemotherapy by protecting against some of the side effects of those treatments.

Enteral glutamine has also demonstrated positive results. In a recent placebo-controlled study, oral glutamine significantly decreased the severity and duration of painful oral mucositis (stomatitis) in autologous bone-marrow transplantation patients. It was similarly helpful in alleviating radiation-induced oral mucositis in a recent randomized pilot trial. Very-low-birth-weight infants orally supplemented with glutamine between days 3 and 30 of life had far less hospital-acquired sepsis than controls (11% versus 30%) and had better tolerance to enteral feedings.

In a placebo-controlled study examining infectious morbidity in multiple trauma patients, oral glutamine was credited with significantly reducing the incidence of pneumonia, sepsis and bacteremia. In another recent randomized study of critically ill patients, supplementation with oral glutamine was said to have significant hospital cost benefits, reducing cost per survivor by 30%.

While claims that glutamine is an effective ergogenic aid are poorly supported, there is some evidence that the substance can help protect against some of the immune impairment that is sometimes seen in exercise "overtraining." Lower resting levels of plasma glutamine have been observed in some athletes suffering from overtraining syndrome, characterized, in part, by transient immunosuppression. In a few preliminary studies, oral glutamine supplementation appears to improve some measures of immunity and to decrease post-exercise infection. Results are not consistent, however, and more research is needed.

Some dated research suggesting that oral glutamine might help curb alcohol craving has not been followed up. One study demonstrated a significant decrease in voluntary alcohol consumption in rats supplemented with glutamine. A subsequent small, uncontrolled study focused on a group of subjects with extensive history of alcoholism. Considerable improvement was noted. More research is needed.

CONTRAINDICATIONS, PRECAUTIONS, ADVERSE REACTIONS
CONTRAINDICATIONS
Supplemental L-glutamine is contraindicated in those hypersensitive to any component of a glutamine-containing product.

PRECAUTIONS
Pregnant women and nursing mothers should avoid supplemental L-glutamine unless prescribed by a physician.

Those with renal or hepatic failure should exercise caution in the use of supplemental L-glutamine.

ADVERSE REACTIONS
Doses of L-glutamine up to 21 grams daily appear to be well tolerated. Reported adverse reactions are mainly gastrointestinal and not common. They include constipation and bloating. There is one older report of two hypomanic patients whose manic symptoms were exacerbated following the use of 2 to 4 grams daily of L-glutamine. The symptoms resolved when the L-glutamine was stopped. These patients were not rechallenged, nor are there any other reports of this nature.

INTERACTIONS
DRUGS
i Human growth hormone: Concomitant use of L-glutamine and human growth hormone may enhance nutrient absorption in those with severe short bowel syndrome. L-glutamine has orphan drug status for this indication.

Indomethacin: Concomitant use of L-glutamine and indomethacin may ameliorate increased intestinal permeability caused by indomethacin. The reported dose used for L-glutamine was 21 grams daily taken in divided doses three times a day. Further, misoprostol is reported to have a synergistic effect with this combination in ameliorating intestinal permeability.

Methotrexate: There is one report that methotrexate may decrease the possible effectiveness of supplemental L-glutamine for chemotherapy-induced mucositis. In another report, nine patients with breast cancer were reported to have decreased symptoms of methotrexate-related toxicity when given supplemental L-glutamine at a dose of 0.5 gram/kilogram/day.

Paclitaxel: In one report, L-glutamine at a dose of 10 grams three times daily, given 24 hours after receiving paclitaxel, appeared to prevent the development of myalgia and arthralgia, adverse reactions of paclitaxel.

DOSAGE AND ADMINISTRATION
L-glutamine is available in capsules, tablets and powder form. It is also available in medical foods for oral and enteral nutrition use and in a dipeptide form for parenteral nutrition use. (See Glutamine Peptides.) Typical doses for those with cancer, AIDS, trauma, burns, infections and other stress-related conditions range from 4 to 21 grams daily. Those who take L-glutamine for these indications must be under medical supervision.

Those with chemotherapy- or radiation-induced stomatitis have taken doses of 2 to 4 grams twice daily or 2 grams four times daily. This was done by dissolving a given amount of L-glutamine in water or normal s****e — one gram dissolves in 20.8 ml of water at 30 degrees Celsius — and using it as a swish and swallow. Again, this must be performed under medical supervision. Since L-glutamine is unstable in water, fresh solutions should be prepared daily.

Those who use supplemental L-glutamine as a possible ergogenic aid use between 1.5 to 4.5 grams daily, taken between meals.

HOW SUPPLIED
Capsules — 500 mg, 750 mg

Powder

Tablets — 500 mg, 750 mg, 1000 mg

LITERATURE
Abcouwer SF, Souba WW. Glutamine and arginine. In: Shils ME, Olson JA, Shike M, Ross AC, eds. Modern Nutrition in Health and Disease. 9th ed. Baltimore, MD: Williams and Wilkins. 1999:559-569.

Anderson PM, Ramsay NK, Shu XO, et al. Effect of low-dose oral glutamine on painful stomatitis during bone marrow transplantation. Bone Marrow Transplant. 1998;22:339-344.

Anderson PM, Schroeder G, Skubitz KM. Oral glutamine reduces the duration and severity of stomatitis after cytotoxic cancer chemotherapy. Cancer. 1998;83:1433-1439.

Antonio J, Street C. Glutamine: a potentially useful supplement for athletes. Can J Appl Physiol. 1999;24:1-14.

Bulus N, Cersosimo E, Ghishan F, Abumrad NN. Physiologic importance of glutamine. Metabolism. 1989;38(Suppl1):1-5.

Byrne TA, Morrissey TB, Nattakom TV, et al. Growth hormone, glutamine, and a modified diet enhance nutrient absorption in patients with severe short bowel syndrome. J Parenter Enteral Nutr. 1995;19:296-302.

Cao Y, Feng Z, Hoos A, Klimberg VS. Glutamine enhances gut glutathione production. J Parenter Enteral Nutr. 1998;22:224-247.

Furukawa S, Saito H, Inoue T, et al. Supplemental glutamine augments phagocytosis and reactive oxygen intermediate production by neutrophils and monocytes from postoperative patients in vitro. Nutrition. 2000;16:323-329.

Furukawa S, Saito H, Ming-Tsan L, et al. Enteral administration of glutamine in purulent peritonitis. Nutrition. 1999;15:29-31.

Haub MD, Potteiger JA, Nau KL, et al. Acute L-glutamine ingestion does not improve maximal effort exercise. J Sports Med Phys Fitness. 1998;38:240-244.

Hond ED, Peeters M, Hiele M, et al. Effect of glutamine on the intestinal permeability changes induced by indomethacin in humans. Aliment Pharmacol Ther. 1999;13:679-685.

Houdijk, APJ, Rijnsburger ER, Jansen J, et al. Randomized trial of glutamine-enriched enteral nutrition on infectious morbidity in patients with multiple trauma. Lancet. 1998;352:772-776.

Huang EY, Leung SW, Wang CJ, et al. Oral glutamine to alleviate radiation-induced oral mucositis: a pilot randomized trial. Int J Rad Oncol Biol Phys. 2000;46:535-539.

Ito A, Higashiguchi T. Effects of glutamine administration on liver regeneration following hepatectomy. Nutrition. 1999;15:23-28.

Lacey JM, Wilmore DW. Is glutamine a conditionally essential amino acid? Nutr Rev. 1990;48:297-309.

Mebane AH. L-Glutamine and mania. Am J Psychiatry. 1984;141:1302-1303.

Neu J, Roig JC, Meetze WH, et al. Enteral glutamine supplementation for very low birth weight infants decreases mortality. J Pediatr. 1997;131:691-699.

Noyer CM, Simon D, Borczuk A, et al. A double-blind placebo-controlled pilot study of glutamine therapy for abnormal intestinal permeability in patients with AIDS. Am J Gastroenterol. 1998;93:972-975.

Rogers LL, Pelton RB, Williams RJ. Voluntary alcohol consumption of rats following administration of glutamine. J Biol Chem. 1955;214:503-506.

Rohde T, MacLean DA, Klarlund Pedersen B. Glutamine, lymphocyte proliferation and cytokine production. Scan J Immunol. 1996;44:648-650.

Rohde T, MacLean DA, Pedersen BK. Effect of glutamine supplementation on changes in the immune system induced by repeated exercise. Med Sci Sports Exerc. 1998;30:856-862.

Sacks GS. Glutamine supplementation in catabolic patients. Ann Pharmacother. 1999;33:348-354.

Wilmore DW, Schloerb PR, Ziegler TR. Glutamine in the support of patients following bone marrow transplantation. Curr Opin Clin Nutr Metab Care. 1999;2:323-327.

Windmueller HG, Spaeth AF. Identification of ketone bodies and glutamine as the major respiratory fuels in vivo for postabsorptive rat small intestine. J Biol Chem. 1978;253:69-76.

Ziegler TR, Benfell K, Smith RJ, et al. Safety and metabolic effects of L-glutamine administration in humans. J Parenter Enteral Nutr. 1990;14:137S-146S

[sonar1234]

Giantz11 thanks i have taken high amounts of glutamine in the past but did quit see any big difference.

I rather go with creatine, one inch on the arms in a week and around 7 pounds of solid water weight LOL

[SVTMuscle*]

some people swear by Glutamine, others have no desire for it. It's a matter of preference, myself personally will be going on Glutamine after this week when I up my cardio alot, which will be taken before my workout and throughout my workout to prevent a high level of catabolism

[MasterofIron]

Glutamine does work. I've been taking it for a while, but I only use the peptide version which is WAY better absorption. It's meant to increase the HGH levels, and I can't argue with that.. because I feel better on it, and grow faster.. (Besides muscles, it's worth noting that my beard grows around 3x faster on this stuff, must be the protein synthesis and HGH.)

I would not bother with the non-peptide crap, (which is about 90% of all glutamine supplements on the market).

[Squatman51]

personally i think glutamine is a good product i have recently tried taking 40-45g of glutamine pwo and my lifts have went up the past week more han usually and i feel better recovered...


Giantz11... i know you said 90% of glutamine gets destroyed in the stomach, is there any way to get more glutamine past the stomach or an ester maybe??

[LetsGetItOn]

It's different for everyone. I didn't really see it do anything for me, but Creatine on the other hand seems to help me out.

[Giants11]

personally i think glutamine is a good product i have recently tried taking 40-45g of glutamine pwo and my lifts have went up the past week more han usually and i feel better recovered...


Giantz11... i know you said 90% of glutamine gets destroyed in the stomach, is there any way to get more glutamine past the stomach or an ester maybe??

Perhaps, but I've seen no data to indicate so. You get plenty of glutamine by jsut eating. So I don't see the need to ever supplement with it unless you are sick or something.

[Vegas1973]

i guess i'll finish the tub of glutamine i got, and probably not buy it again. I thought it was better suited for recovery than actual muscle growth. After reading all this thread has, I guess its probably money better spent on other, more basic suppliments.

[tinyguy2]

ill go with beradi on this one cause he knows his stuff...all those studys supporting glutamine are from ages ago or bs.

I read beradis other articles saying that alot of companies put out slander aganist him using studies that had nothing to do with glutamine and body building.

eat some food and dont buy glutamine

[Alpha-Male]

you get plenty of EVERY amino acid from the massive amounts of protein you eat...all studies and articles aside, which should be enough but apparently aren't, pick up a basic A&P book (i'll lend you mine if ya need)...a normal, healthy, functioning body can only break down and make use of so much of any amino acid (among other nutrients)...the rest is WASTED...even too much protein has been shown to maximize in terms of nitrogen retention and synthesis...

and enough of this "i know this guy that's frikin' huge, and he uses it so it MUST work"....dude, c'mon, i promise you, that guy ain't gettin' huge from Glutamine...one day, see if you can get a complete list of his "supplementation", i think you'll find a better answer to the "mystery"...heh

alpha