Magnesium L-threonate (MgT) is a highly absorbable form of magnesium able to cross the blood-brain barrier and to easily force its way through cell membranes.
Unlike most dietary magnesium supplements, magnesium L-threonate is not generally used to overcome magnesium deficiencies but is used to support cognitive function. If you are only looking to address general magnesium deficiency you may wish to take magnesium citrate (typically at a dose of 200 to 400 mg).
Chelations with the vitamin C metabolite L-threonate (threonic acid) are known to enhance mineral bioavailability. In this case, it allows magnesium to be better delivered to the parts of the body, such as the brain, where it is required. It has been reported that the bioavailability of magnesium taken in the form of magnesium L-threonate is enhanced when dissolved in milk . The bioavailability in the brain is also much greater than seen with most other forms of magnesium tablets e.g. magnesium glycinate and magnesium oxalate .
With regards to the brain, learning and memory are fundamental functions that can be affected by both environment and diet. When taken orally, magnesium L-threonate has been shown to support memory (long and short term), enhance learning abilities, and improve working memory in rats .
In older rats there was also a positive effect on the maintenance of task completion ability. The same scientific research work also reported that a higher density of synaptophysin- (synaptic vesicle protein p38) and/or synaptobrevin-positive puncta occurred in certain subregions of the hippocampus strongly correlated with improved memory functions. The group also suggested that synaptic plasticity was enhanced in rats. Therefore using magnesium L-threonate to help promote levels of magnesium in the brain is likely to support synaptic facilitation, potentiation, memory, and learning in healthy individuals.
Further research has suggested that elevation of magnesium levels in the brain can help to support a healthy response to anxiety and other mental mechanisms . Elevated magnesium is thought to enhance plasticity in the hippocampus and the prefrontal cortex. The researchers demonstrated that increased magnesium levels resulted in an increase of signaling involving NMDA receptors and increased presynaptic puncta density in the prefrontal cortex in relation to fear memory in rats, these phenomena did not occur in the basolateral amygdala, suggesting that brain magnesium may act in a regional specific manner in the memory formation processes.
Magnesium (Mg2+) is an abundant mineral that is found in many foods. Despite this its intake levels in the general US population is lower than the RDA provided by the Food and Nutrition Board . Some of the foods that are naturally rich in magnesium include almonds, cashews, edamame beans, salmon, soymilk, broccoli, peas, and spinach.
Severe deficiency is rare and tends to occur in people with diseases, especially those related to the kidney (which plays a major role in magnesium homeostasis, with around 120 mg of Mg being excreted by urine per day).
An adult body typically contains around 25 grams of magnesium. The majority of which is stored in cells and in the bones (50 to 60%), where it has a major role in bone structure and remodeling. It is also needed for RNA and DNA synthesis, energy production, glycolysis, oxidative phosphorylation, and for use by the glutathione antioxidant. The levels of magnesium in blood serum are kept under strict control, and typically range from 0.75 and 0.95 mmol)/L .
Magnesium has been reported to support cardiovascular health , help support healthy blood sugar levels (most likely through its role in glucose metabolism), to influence osteoblast and osteoclast activity and concentrations of vitamin D during bone formation and removal , it is also associated with neurotransmitter release , so healthy levels of the mineral may help support a healthy response to headaches.
Research into the use of magnesium as a ‘brain booster’ in humans is currently being performed by Magceutics with the aim of better delivering and increasing levels of magnesium ions in the brain. Some of the research aspects of the Magtein supplement investigated included responses to anxiety and sleep quality.
Dr. Guosong Liu, a neuroscientist from Tsinghua University in Beijing, is leading this research. His team previously demonstrated the role of the NMDA receptor 2B (NR2B) in increasing memory in the brain of mice through the strengthening of synaptic connections . The group later went on to demonstrate the role of magnesium in supporting synaptic changes  and in promoting healthy memory .
Sleep quality has also been suggested to be enhanced in humans, in older people .
Further research at the Max Planck Institute of Psychiatry in Germany by Harald Murck strongly supports that intravenous magnesium may support cognitive function during sleep . As Magnesium L-threonate is able to deliver magnesium across the blood-brain barrier to areas where it is required by the brain it may support cognition in healthy individuals.
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