Magnesium plays a vital role in learning and memory in its involvement with N-methyl D-aspartate (NMDA) receptors, which are critical for spatial memory.  Clinical studies have shown magnesium to be a positive regulator of synaptic plasticity, which is crucial for effective communication between neurons. Increasing magnesium concentration in the extracellular fluid has been shown to permanently enhance synaptic plasticity in these areas of the brain.  Increasing brain levels of magnesium has been shown to treat cognitive impairment and prevent memory decline. 
Cognitive function declines with age, often as a result of brain atrophy and the loss of neurons, axons, synapses, and the reduction of synaptic plasticity. 
Pre-clinical studies show that levels of brain magnesium are a critical factor controlling synapse density and plasticity. Intracellular magnesium is critical for proper neuronal energy supply, and increased levels of magnesium are shown to enhance both functional synapse density and plasticity. 
Benefits of magnesium l-threonate
Supports memory function
Magnesium L-threonate’s superior bioavailability makes it one of the few magnesium compounds that can significantly increase magnesium concentrations in the brain. When taken consistently for several weeks or months, L-threonate can increase synaptic connections in the brain, improving learning capacity as well as short- and long-term memory, and working memory.
Supplementation with magnesium l-threonate can enhance both long and short-term memory and improve cognitive function and attention. It is also shown to support neuron cell health and regeneration while increasing neural plasticity.
Regenerates the aging brain
Unlike most forms of magnesium, magnesium L-threonate can cross the blood-brain barrier and effectively enhance brain magnesium concentration.
A study involving older adults found that six weeks of supplementation with magnesium L-threonate significantly improved executive function and working memory. After 12 weeks, the adults showed improvement in episodic memory.  A similar study published in the scientific journal Neuron reported that magnesium l-threonate supplementation over five years enhanced memory in both young and aging animals and prevented memory impairment. Behavioral tests showed that supplementation improves cognitive functioning as well as increasing synapses in the brain. 
May help alleviate stress
A low magnesium/calcium ratio can increase feelings of stress and anxiety due to the higher production of catecholamines in the brain. Magnesium deficiency
is also linked to increased anxiety, psychological stress, migraines
, and other associated symptoms. These symptoms of stress - particularly migraines - can be both prevented and relieved with high-dose magnesium. 
Magnesium supplementation appears to alleviate the stress response by inhibiting the release of various stress hormones. 
May support healthy mood
Magnesium supplementation increases the availability of the neurotransmitter gamma-aminobutyric acid (GABA), which has a calming effect on the mind. 
Supplementation with magnesium l-threonate may even provide an antidepressant effect by increasing brain-derived neurotrophic factor (BDNF) expression.  In addition, it has been found to support the serotonin system by acting as a cofactor for tryptophan hydroxylase, an enzyme involved in the synthesis of serotonin. 
Choosing a good supplement
Despite the ready availability of magnesium supplements, each product will vary substantially in terms of bioavailability and therefore its benefits.
Magnesium L-threonate is a chelated form of magnesium that has been clinically proven to cross the blood-brain barrier. Chelation refers to the bonding of the magnesium molecules to another molecule, enhancing stability, absorption, and bioavailability. This patented magnesium is clinically proven to increase magnesium levels in human brain cells, enhancing memory, attention span, and learning.
A clinical trial published in a peer-reviewed medical journal found that adults supplemented with Magtein showed significant improvements in four cognitive areas: memory, concentration, and anxiety.  It also reduced the participants’ biological brain age by around 9.4 years. Taking magnesium l-threonate for sleep
was also more effective than other forms of magnesium.
• Readily crosses the blood-brain barrier for efficient uptake in the brain
• Increases brain plasticity, supporting the ability of neural cells to grow and change, enhancing memory and learning 
• Increasing brain-derived neurotrophic factor (BDNF), a protein that stimulates the formation of new brain cells
• Prevents and restores short-term memory loss induced by nerve injury 
• Effectively increases brain levels of magnesium to treat cognitive impairment 
• Improves executive function, working memory, attention, and episodic memory 
• Helps to prevent memory decline 
No significant adverse effects have been reported from taking l-threonate. Its superior bioavailability in the gastrointestinal tract means that it is effective at lower doses than most magnesium products, which reduces the risk of digestive upset or bowel looseness.
However, as with any new supplement regime, it is important to first consult your health practitioner.
Magnesium l-threonate: When to take
For optimal cognitive benefits, the recommended dosage is 1,000 mg twice daily. This is best taken morning and night.
How long does it take for magnesium l-threonate to work?
Most people taking magnesium L-threonate can expect to see benefits within three to six weeks. These results will vary between individuals depending on their health status, magnesium levels, and other factors. In most cases, magnesium L-threonate should be taken consistently for at least 3-4 months in order to restore low levels and experience the full benefits.
Magnesium l-threonate has benefits for all ages, from seniors who are concerned about cognitive decline and/or memory loss to younger people who want to enhance their learning and memory. This powerful supplement may also benefit those who struggle with stress, depression, insomnia, and anxiety.