L- glutamine is an amino acid. It’s also probably my most favorite supplement of all time, one I take pretty much all the time. No, L-glutamine is not sexy. You won’t find it commanding full-page ads in your favorite health & fitness or body building magazines. And nobody talks about it much.
But really, it is an amazing supplement that anyone — the dieter, the fitness fanatic and body builder, the chronically ill, cancer patients, and those recovering from surgery should be taking regularly.
Amino acids like l-glutamine are the “building blocks” of protein, and they are classified as “essential” (meaning the body cannot synthesize them itself and must obtain them from the diet), or “non-essential” (meaning the body can make them from various raw materials).
Glutamine is considered “conditionally-essential” meaning normally the body can make enough to meet its own needs. However, in times of stress or trauma the body can run low on l-glutamine, and needs to obtain extra from an outside source.
Glutamine is also the most abundant amino in the human body, and is is involved in more metabolic processes than any other amino acid. Its functions are many and its role is critical.
Normally glutamine is marketed to body builders because it has been shown to enhance muscle recovery, display anti-catabolic behavior, increase protein synthesis, and muscle hydration — all important stuff, you’ll agree.
Contrary to popular belief, glutamine does not seem to improve performance. In fact, there are plenty of clinical studies that indicate glutamine has no positive effect on muscular performance whatsoever even at the appropriate high dosage. (See J Strength Cond Res. 2002 Feb;16(1):157-60, Sports Med. 2003;33(5):323-45).
Of course, glutamine works indirectly to make you stronger — by improving glucose regulation, immune function, protein synthesis and promoting a positive nitrogen balance (see Can J Appl Physiol. 1999 Feb;24(1):1-14, JPEN J Parenter Enteral Nutr. 1990 Jul-Aug;14(4 Suppl):40S-44S).
Therefore, it is still a vitally important supplement that should be used by every training athlete.
However, lately I’ve become convinced that glutamine shows great promise for dieters, diabetics, and anyone trying to lose weight or battle fluctuating blood sugar levels. In my experience, glutamine is an amazing “craving killer.” Although glutamine’s “diet” usage is not new, it is not commonly used to reduce craving for sweets.
Those of you familiar with the Atkins’ diet know Dr Atkins recommends supplementing with it during his diet’s initial period of extreme carbohydrate restriction to protect lean muscle mass. L-glutamine can also be metabolized into glucose for fuel if necessary — again, making it a critical supplement for low carbers as well.
However, new studies are examining the link between glutamine and glucose management in both the gut (where glutamine plays a huge role) and the kidneys and other tissues (see Kidney Int. 1999 Mar;55(3):778-92, Curr Opin Clin Nutr Metab Care. 2001 Jul;4(4):267-71, Curr Opin Clin Nutr Metab Care. 2005 Jul;8(4):445-9, Braz J Med Biol Res. 2003 Feb;36(2):153-63. Epub 2003 Jan 29).
My own experience with glutamine (which does not constitute real evidence, of course) appears to bear out its glucose regulating effects.
I’ve found that glutamine supplementation has been amazingly effective at absolutely eliminating late night junk food cravings.
My normal solution for cravings such as these has been to take 300 mg of alpha lipoic acid prior to my meals. Lately however, even this had proved to be ineffective.
Glutamine, on the other hand, worked absolute miracles for me! (I am taking approximately 30 grams of glutamine per day in two divided doses. I found it took about a week to realize the effects, but once I did… wow!).
As such, l-glutamine has now become my #1 recommended supplement as a craving killer!
Despite its low profile, even l-glutamine has been touted as a miracle weight loss supplement by a few “less than scrupulous” marketers.
A recent study published by The American Journal of Clinical Nutrition has shown that oral supplementation with as little as 2 grams (about half a teaspoon) of glutamine significantly elevated circulating growth hormone levels! Because HGH (human growth hormone) has powerful anabolic (muscle building) and fat burning powers, various supplement makers have tossed a few grains of l-glutamine into their compilations so as to “validate” their outrageous claims.
The biggest contributors to this problem are the makers of the “lose weight while you sleep” products. Some add a tiny bit of glutamine into a product’s formulation, and claim the powerful fat burning powers of HGH will burn the weight off you while you sleep.
Here’s the first problem with that claim…
In order to get the benefits of this amino, you need to supplement in significant amounts — anywhere between 2-5 grams per serving. Why? Well, one of the largest consumers of l-glutamine in the body is the small intestine — and you must take in significant amounts in order to get any past this glutton and into your bloodstream. Most of the “miracle products” contain only trace amounts of l-glutamine; not enough for you to obtain ANY benefit.
In addition, glutamine is relatively unstable in solution form.
Yes, growth hormone has both anabolic and fat burning powers, but it has yet to be demonstrated that relatively brief periods of increased serum growth hormone has any significant effect on weight loss. Again, it’s a case of putting the cart before the horse for the sake of a few dollars. It’s a shame, because glutamine is a very worthwhile supplement — especially for dieters.
Glutamine’s Other Benefits
So far, I’ve discussed glutamine’s benefits mostly as they pertain to dieters or athletes. However, numerous studies show it has a myriad of benefits…
- Promotes gastrointestinal health
- Speeds the healing of wounds, and is of great use as a “surgical recovery” supplement
- Boosts the immune system (in dosages of 20-40 grams daily)
- Protects the liver from damaging effects of chemotherapy
- Curbs the desire to consume alcohol
- As a building block of several important neurotransmitters supplementation may contribute to enhanced brain function
… As well as all the other benefits discussed here, of course.
Supplementing With Glutamine
L-glutamine is a tasteless, odorless white powder. It can be mixed with water, juice, or diet pop, as long as it is consumed immediately (I recommend mixing with juice, otherwise it tastes like “chalk-water”). To get the greatest benefits from L-glutamine, I recommend taking 10 -15 grams (2-3 teaspoons) twice daily — on an empty stomach before bed and immediately upon rising.
Bodybuilders (especially those on “cutting phases”) and those on the severe carbohydrate restriction period of the Atkins diet may wish to double this, and add two more divided doses. If you’re looking to use glutamine as a craving killer, give it a week before you expect to see any results.
Any way you want to slice it, glutamine is a winner. Two thumbs up, highly recommended!
You can buy glutamine just about anywhere online, But I recommend BodyBuilding.com. Don’t buy capsules — you’ll need to take too many for that to be cost effective or practical. Buying 2.2 lbs. or 1 kilogram worth of glutamine is your best bet — at 30 grams per day, that will last you about a month.