Gamma Aminobutyric Acid (GABA) is found in high concentration in the eyes and brain as a non-essential amino acid. The brain is able to produce GABA, but because of environmental or health reasons, levels can drop. The result is insomnia, irritability or anxiety. Depression has also been seen to be associated with low GABA levels. GABA is the most important inhibitory neurotransmitter. Because it helps to prevent the transmission of cell-to-cell messages, GABA may assist your ability to deal with stress and anxiety. It can also encourage sleep and relaxation. GABA has also been known to stimulate the pituitary gland, helping it to release more Human Growth Hormone (HGH). This powerful substance limits fat cell development and helps muscles to grow. In some studies, GABA helped participants lose fat. In people over the age of 40, HGH levels may drop, resulting in sleep difficulties. GABA’s ability to boost HGH levels may lead to better sleep.