ZMA is a supplement formulation composed of zinc monomethionine aspartate, magnesium aspartate, and vitamin B6 that is claimed to increase testosterone levels. Supplementation with ZMA was first tested in humans by the supplement’s manufacturer, which found that ZMA raised testosterone levels and increased muscle strength and power in athletes. However, follow-up studies by independent groups have failed to replicate those initial results.
It is possible that ZMA can cause weird dreams, and the anecdotes support this; however, since this has not been directly investigated the best 'proof' that can be given is weak.
This claim has not been investigated much, but a pilot study[reference|url=http://www.ncbi.nlm.nih.gov/pubmed/11883552|title=Effects of pyridoxine on dreaming: a preliminary study|published=2002 Feb|authors=Ebben M, Lequerica A, Spielman A|journal=Percept Mot Skills] suggests that a dose of 250mg pyridoxine can alter dream perception in college aged men, through a hypothesized increased conversion of tryptophan to serotonin. This dose of B6, however, is much higher than that occurring in ZMA products; which tends to range in the 10-50mg range and usually at the lower end.
One other study has reported synergism between B6 and Magnesium in regards to anxiety reduction, when the subjects were women experiencing PMS;[reference|url=http://www.ncbi.nlm.nih.gov/pubmed/10746516|title=A synergistic effect of a daily supplement for 1 month of 200 mg magnesium plus 50 mg vitamin B6 for the relief of anxiety-related premenstrual symptoms: a randomized, double-blind, crossover study|published=2000 Mar|authors=De Souza MC, Walker AF, Robinson PA, Bolland K|journal=J Womens Health Gend Based Med] it is theoretically possible that the ZMA formulation enhances the actions of pyridoxine allowing the previous research's results to be relevant.
- ^Kerksick CM, Wilborn CD, Roberts MD, Smith-Ryan A, Kleiner SM, Jäger R, Collins R, Cooke M, Davis JN, Galvan E, Greenwood M, Lowery LM, Wildman R, Antonio J, Kreider RBISSN exercise & sports nutrition review update: research & recommendationsJ Int Soc Sports Nutr.(2018 Aug 1)
- ^Brilla et al.Effects of a Novel Zinc-Magnesium Formulation on Hormones and Strength.Journal of Exercise Physiology.(2020)
- ^Wilborn CD, Kerksick CM, Campbell BI, Taylor LW, Marcello BM, Rasmussen CJ, Greenwood MC, Almada A, Kreider RBEffects of Zinc Magnesium Aspartate (ZMA) Supplementation on Training Adaptations and Markers of Anabolism and CatabolismJ Int Soc Sports Nutr.(2004 Dec 31)
- ^Koehler K, Parr MK, Geyer H, Mester J, Schänzer WSerum testosterone and urinary excretion of steroid hormone metabolites after administration of a high-dose zinc supplementEur J Clin Nutr.(2009 Jan)