Yes. I bought it as a sleep aid too, and it made me wanna jump out of my skin. Doesn't seem like it crosses the blood/brain barrier either, which would make it worthless as a growth hormone stimulator.
5g isn't too much, but might be overkill. 3g seems to have some positive results with GH
Strength athletes who take 3 g of the supplement GABA quadruple their growth hormone production during and after a training session. Sports scientists at Shenandoah University discovered this when they did an experiment with 11 men (average age 23), all of whom were regular weight trainers.
I'm going to go ahead call BS. It shouldn't work that way, it would need to reach the brain to illicit a response like endogenous GABA (GH secretion).
I would be more likely to believe the act of training itself spiked the GH, though I don't know about a 4 fold increase, but hormone levels fluctuate throughout the day so it isn't entirely unreasonable.
11 Men is a very small sample, as well. There's no reason to to use more on something that most would consider almost harmless. It leaves the study underpowered, at best.
When i take about 3g 30-45 minutes before bed, i sometimes get a really "oh my god, my skin is on fire" sort of feeling, and my heart seems to race for a few minutes...but then i relax and sleep great afterwards, but i dont know the cause behind it.
Anyone have any knowledge as to the systemic effects of GABA?
Just because it's primarily neurally active and doesn't cross the BBB doesn't make it worthless, it could act on another area of the body and send signalling compounds to the brain to induce effects vicariously.
GABA A receptors are acted on by benzodiazepines, for instance. GABA B receptors are acted on by GHB.
GABA A receptors increase conductance of Cl into the cell creating a larger negative barrier that must be overcome before threshold is reached and an action potential can be transmitted.
GABA B receptors hyperpolarize the cell by allowing K into the cell, preventing Na channels from opening and conducting the signal.
Most of the effects are primarily CNS related, though there are GABA receptors in the periphery I don't think they're there in any appreciable quantity or that supplementing with GABA would have any measurable effect.
I don't understand why everything I am reading shows that benzos will increase growth hormone, but alchohol will decrease it. One would expect that as a result of their similar effects and mechanism of action that they would have a similar effect on ones hormonal profile.