Just bought some. Before I take it.. I need some imput. Do they work at all?
Is this the one that contains GABA and L-Theanine? If so the best way to take is is to drop each capsule into the toilet bowl and flush. You will achieve exactly the same result as swallowing it while avoiding the dangers of accidentally choking on it.
Orally taken GABA cannot pass through the blood-brain-barrier. L-Theanine is promoted as a GABA booster which is only partly true. Not that it matters since every reasonable healthy brain doesn't lack GABA. It is produced as a byproduct during the Kreb's (aka citric acid) cycle that converts glucose to adenosine triphosphate (ATP) the main fuel of the brain (and the body generally). The brain is awash with the stuff, so much so that the blood-brain-barrier contains billions of molecular pumps to suck GABA from the brain for disposal (Kakee A
, 2001). Some antidepressants also reduce GABA levels in areas of the brain associated with anxiety such as the amygdala and hippocampus, see for example (Reagan LP
The problem isn't a lack of GABA, but a lack of benzo-GABA complex receptors1
. Trying to correct this by increasing GABA levels in the brain is akin to fixing faulty sparkplugs by filling the gas tank to overflowing.
The Zen Life supplements website claims that GABA and L-Theanine promote production of serotonin. No they don't. Theanine actually reduces serotonin synthesis and speeds up its breakdown (Yokogoshi H, 1995 - PDF
, p3; Yokogoshi H
, 1998), which is a good thing because you don't want more serotonin in your brain. See: Serotonin: The 'chemical imbalance' myth
To end on a positive note, apart from the choking risk, this supplement shouldn't do any harm. The L-Theanine might do something positive if there is enough in every capsule (dose not specified) and provided the other ingredients don't get in the way. However, Omega-3s/fish oil supplements and exercise are likely to do you more good.
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