NOW Magtein Magnesium L-Threonate - 90 CapsulesMagnesium L Threonate Supports Memory and Learning Promotes Brain Health Magnesium (Mg) is an essential mineral best known for its role in bone and nervous system function.* Recent research has demonstrated that it is also critical for normal brain health and normal cognitive function by maintaining the density and stability of neuronal synapses.* However, most forms of Mg are not easily absorbed into the nervous system.* Magtein is a patented form of