|GABA tea contains comparably low amounts of GABA (180mg/100g; Wang. 2006) and still or, as the results of the study at hand suggest, rather thus helps with sleep (Cheng. 2009).|
I don't care if everything or anything of what I wrote before is accurate. What I do care about, though, are the results Xie et al. present in their latest paper in the Journal of Animal Physiology and Animal Nutrition.
The name of the journal gives it away: We are - again - dealing with animal data, but there is no reason to assume that the effect the researchers observed in obese mice would be completely irrelevant for human beings. The previously cited beneficial effects on the pancreas of diabetic animals have after all been confirmed in in vitro studies with human cells, already.
|High amino acid levels in the blood of obese indiv. are not a result of their high protein intake, they're caused by low uptake and + high protein breakdown.|
Now, contrary to what some "anti protein" gurus are going to tell you, the increased amounts of amino acids are not of dietary origin. Rather than that they are released as a consequence of the increase in protein breakdown - specifically muscle protein breakdown - in obese and diabetic individuals.
Beware of high dose GABA (>3g) supplementation on empty! Those 100mg of GABA are very unlikely to have any negative effects on your health. With higher amounts, on the other hand, specifically if they are taken on empty and thus rapidly absorbed, side effect can occur. Anxiety, slowed breathing, weakness, they all are probably caused by peripheral effects (not in the brain), but this does not make them desirable, either. So practically speaking this means that you best stick to low / divided doses and if you take more, take it with food.Xie et al did now speculate that the previously cited ability fo gamma-aminobutyric acid (GABA) to reduce high-fat diet (HFD)-induced hyperglycaemia could be brought about by the effects GABA, the chief inhibitory neurotransmitter in the mammalian central nervous system exerts on peripheral organ tissue, like skeletal muscle.
|Figure 1: GABA ameliorates / reverses the HFD-induced increase in markers of ox. damage in skeletal muscle (Xie. 2014)|
- CONTROL: rodents on control diet
- HFD: rodents on high fat diet (high fat + high energy; HFD)
- GL: rodents on HFD supplied with 0.2%,
- GM: rodents on HFD supplied with 0.12%, and
- GH: rodents on HFD supplied with 0.2% GABA in drinking water
What else can GABA do for you? 80 mg of GABA reduce blood pressure in adults with mild hypertension (Matsubara. 2002). It can speed up the recovery of an alcohol intoxicated liver (Soh. 2003). And it will trigger an acute increase in growth hormone (with no proven benefit on muscle gains; Powers. 2013). The often-cited beneficial effects on sleep, on the other hand, are far from being confirmed - results of the study at hand suggest that this may be a result of the fact that you really have to hit the sweet spot to maximize specific effects and minimize the metabolism of GABA in the liver - taking high doses may thus trigger its excretion, while taking very low doses may not be enough get the GABA across the blood brain barrier (Kakee. 2001).During and after the trial, the scientists observed significant increases in muscular oxidative stress (see Figure 1), protein oxidation, hyperglycaemia, as well as the previously cited plasma free amino acid disorders that included an augmented level of GABA in the blood
|Figure 2: Body weight, rel. muscle weight and blood glucose expressed relative to control (Xie. 2014)|
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- Xie, et al. "Effect of GABA on oxidative stress in the skeletal muscles and plasma free amino acids in mice fed high-fat diet." Journal of Animal Physiology and Animal Nutrition (2014).