|The health impact of the vast gene pool in our guts has long been underrated.|
If you have been around "forever", you may yet also remember that there's one thing glutamine appears to do that no-one actually has on the radar, when he or she's browsing the storefronts of his or her favorite supplement vendor: Improvements in insulin sensitivity as those I've written about for the first time in 2010 and downstream anti-diabesity effects as they've been demonstrated more recently by Mansour et al. (2014) in a quite impressive 6 week study, in the course of which "3x30g/day Markedly Improved Cardiovascular Risk Factors & Body Comp in 6 Weeks" (reread the full article).
Now, back in the day, I was not really able to explain how "exactly", the most abundant amino acid in the body was able to induce significant decreases in body fat even though the subjects were not dieting. With the publication of the results of a recent study from the State University of Campinas in Brazil, however, the evidence that these benefits may be a consequence of the modulatory effects of glutamine on the (pro-inflammatory) microbiome of obese individiuals are accumulating.
In said pilot study, Alessandra Zanin Zambom de Souza and her colleagues aimed to "determine whether oral supplementation with L-glutamine (GLN) modifies the gut microbiota composition in overweight and obese adults" (de Souza. 2015).
"In this double-blind, 14-d study, participants [thirty-three overweight and obese adults, ages between 23 and 59 y and body mass index between 25.03 and 47.12 kg/m²] were randomly divided into two groups: glutamine (GLN) and alanine (ALA). We used alanine as control to give the volunteers the same amount of calories. Participants received a kit containing small packs with 15 g of amino acid (GLN or ALA) each, with varying artificial flavors, to be diluted in 200 mL of water at the time of intake. Participants were instructed to take two packs at any convenient time of the day, totaling 30 g/d of amino acid, while maintaining their usual diets and physical activities" (de Souza. 2015).After 14 d of supplementation, adults in the GLN group exhibited statistically significant differences in the Firmicutes and Actinobacteria phyla compared with those in the ALA group.
reread it) and the existing evidence suggesting that the ratio of Firmicutes to Bacteroidetes, a good biomarker for obesity (Ley. 2005 & 2006 | Ley et al. (2006), for example found a linear increase in bacteriode abundance with weight loss), the observed decrease in the F:B ratio from from 0.85 to 0.57 in the glutamine group may in fact provide a mechanistic explanation for the previously observed medium-term benefits of high-dose glutamine supplementation in the obese. Benefits that may be augmented by the recently proven and probably mechanistically related ability of glutamine to attenuate oxidative stress and the proinflammatory responses as they would occur, when endotoxins from the gut make it into your blood stream (Cruzat. 2014) - something you may, by the way, also expect to see if you are a green or black tea connoisseur of which Henning et al. have recently been able to show that it induces similarly positive changes in the firmicute to bacteroides ratio as glutamine (Henning. 2015).
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