GABA (gamma aminobutyric acid/gamma amino-butyric acid) is an amino acid synthesized in the brain that acts as a neurotransmitter inhibitor and is associated with reducing the incidence of seizures and depression (Sources:
Advances in Experimental Medicines and Biology, 2004, volume 548, pages 92–103; and
Archives of General Psychiatry, July 2004, pages 705–713). Cosmetics companies include GABA in products and then claim that topical application relaxes muscles, thus sparing consumers from going through Botox injections. However, GABA has not been proven to relax muscles and reduce the appearance of wrinkles or expression lines when applied topically. Cosmetics companies are hoping that consumers will associate the topical application of products containing GABA with its internal function of controlling the manner in which nerve impulses fire. There is no substantiated research proving GABA works in this manner when applied topically, and if it did, it would be cause for alarm. Because if GABA worked as stated and you applied it to your entire face, what’s to stop it from affecting the muscles around your mouth, jaw, or neck? If it really relaxed muscles upon application, consumers would see more skin sagging, not to mention problems controlling the (relaxed) muscles in your fingers (assuming they come in contact with the product).
Lastly, the whole nonsense of using GABA in cosmetic products is refuted by the fact that GABA does not work alone to exert its effect internally on nerves. It requires many other substances (substances that are not present in the skin-care products containing GABA) for it to prevent nerves from being triggered and causing muscles to relax (Sources: www.emedicine.com; www.naturaldatabase.com).