Magnesiun-l-threonate consists of magnesium bonded to the organic acid, threonic acid, and is denoted by the chemical formula Mg(C4H7O5)2.
Magnesiun-l-threonate has high brain bioavailability. It is the only magnesium compound that has been shown to effectively raise the brain’s magnesium levels.
In pre-clinical models, L-threonate contained in Magnesiun-l-threonate boosted magnesium levels in spinal fluid by an impressive 15% compared to no increase with conventional magnesium. 
Research on Magnesiun-l-threonate has been led by the biopharmaceutical company Magceutics of Hayward, California. They tradmarked the product named Magtein(TM). They began testing Magtein,’s(TM) ability to boost magnesium ion (Mg2+) levels in the brain in 2012 and the results have been impressive. 
Gao Sheng-Li;Yang Xu-Wu;Chen San-Ping;Ju Zhan-Feng (2002). “Synthesis and Standard Enthalpy of Formation of Magnesium L-Threonate”. Acta Phys. -Chim. Sin. 18 (11): 994–997.
Magnesium Supplement Helps Boost Brainpower, Science Daily, Feb. 2, 2010
Inna Slutsky, Nashat Abumaria, Long-Jun Wu, Chao Huang, Ling Zhang, Bo Li, Xiang Zhao, Arvind Govindarajan, Ming-Gao Zhao, Min Zhuo, Susumu Tonegawa, and Guosong Liu (2010). “Enhancement of Learning and Memory by Elevating Brain Magnesium”. Neuron 65 (2): 165–177. doi: 10.1016/j.neuron.2009.12.026. PMID 20152124
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