Magnesium L-threonate is the ONLY magnesium form with published evidence for increasing brain magnesium levels in animal models. Invented at MIT by Guosong Liu, the premise is that standard magnesium forms don't cross the blood-brain barrier efficiently, while L-threonate (a vitamin C metabolite) acts as a carrier that delivers Mg²⁺ specifically to the brain. A 2010 Neuron paper showed it enhanced learning, memory, and synaptic density in rats. The 2016 human trial (MATRIALS) showed improved cognitive abilities in older adults. However: only 144mg elemental magnesium per full dose — you need additional magnesium from other forms for systemic needs. This is a BRAIN-SPECIFIC magnesium, not a general magnesium replacement.
L-threonate (a metabolite of vitamin C) acts as a unique carrier molecule: (1) it increases the expression of the magnesium transporter protein in the BBB (specifically, L-threonate upregulates BBB Mg transporters); (2) the L-threonate-Mg complex crosses the BBB more efficiently than inorganic magnesium; (3) once in the brain, Mg²⁺ enhances NMDA receptor signaling at the NR2B subunit — this subunit is the "plasticity switch" that enables long-term potentiation (LTP, the cellular basis of memory); (4) brain Mg²⁺ increases presynaptic release probability while simultaneously increasing the number of functional synapses (higher synaptic density); (5) in the prefrontal cortex, elevated Mg²⁺ enhances fear memory extinction — the process by which learned fear responses are overwritten.
Based on independent third-party laboratory analysis
Category pass rate: ~80% of magnesium products passed independent laboratory testing. However, form accuracy is a MAJOR issue — some brands label one form but contain a different (cheaper) form.
Contamination risk: Low risk category. Heavy metals rarely an issue in mineral supplements at tested doses.
Reviewed by the Scan Dose Research Team and Clinical Advisory Board | Last updated:
Not medical advice. Based on published clinical research and systematic reviews.