Both gamma-aminobutyric acid, or GABA, and zinc magnesium aspartate, or ZMA, can commonly be found as supplements. Consumers use both supplements for a variety of purposes, only a few of which actually work. While minerals and specific acids play a role in various functions within your body, using them in supplemental form requires knowledge of mineral deficiencies or problems following a proper diagnosis. Do not use any supplement before consulting a health care provider.
GABA is a neurotransmitter, which means it is a specific acid that affects the transmissions of impulses in your brain and nervous system. The functions of GABA are inhibitory, as it inhibits binding agents allowing greater flow of other elements, particularly chloride. This has the effect of increasing the stimulation of various aspects of your central nervous system and possibly your pituitary gland. Stimulation of the pituitary gland may lead to an increase in the production of growth hormone, according to a 2008 study published in "Medicine and Science in Sports and Exercise."
GABA may have a slight effect as a relaxant or in providing anti-anxiety effects, according to a study published in "Current Opinion in Pharmacology" in 2006. These effects in no way replace treatment by a licensed physician and should not be used in place of prescribed medication. Other reported uses of GABA abound, such as increased strength, use as a pre-workout stimulant and enhanced recovery from exercise. No evidence exists to support any of these claims.
Zinc Magnesium Aspartate
ZMA is a combination of two minerals, zinc and magnesium, and also contains vitamin B6. Most individuals consuming a balanced diet should get enough zinc and B6. Magnesium may or may not be lacking in your diet, depending on your dietary composition. A diet rich in leafy greens will provide magnesium, but those lacking greens in their diet may be deficient. None of the compounds in ZMA have any specific effects as neurotransmitters.
ZMA is commonly sold as a bodybuilding supplement, with the original developer claiming that it increased testosterone. In a study published in the "Journal of the International Society of Sports Nutrition" in 2004, ZMA supplementation showed no increase in testosterone. In a follow-up study published in the "European Journal of Clinical Nutrition" in 2007, ZMA once again showed no increases in testosterone of any kind among study participants. No evidence supports the use of ZMA as anything other than a mineral supplement.
- "Medicine and Science in Sports and Exercise"; Growth Hormone Isoform Responses to Gaba Ingestion at Rest and After Exercise; M.E. Powers, et al.; January 2008
- "Current Opinion in Pharmacology"; Glutamate- and GABA-Based CNS Therapeutics"; A.C. Foster, et al.; February 2006
- "Textbook of Biochemistry with Clinical Correlations"; Thomas M. Devlin; 2010
- "Journal of the International Society of Sports Nutrition"; "Effects of Zinc Magnesium Aspartate (ZMA) Supplementation on Training Adaptations and Markers of Anabolism and Catabolism"; C.D. Wilborn, et al.; December 2004
- "European Journal of Clinical Nutrition"; Serum Testosterone and Urinary Excretion of Steroid Hormone Metabolites After Administration of a High-dose Zinc Supplement; K. Koehler, et al.; September 2007