A recent paper published in the journal Neuron, entitled “Enhancement of Learning and Memory by Elevating Brain Magnesium,” shows that a new magnesium supplement substantially increases cognitive functioning in rats.
Magnesium, an essential element, is found in dark, leafy vegetables such as spinach and in some fruits. Those who get less than 400 milligrams daily are at risk for allergies, asthma and heart disease, among other conditions. In 2004, Guosong Liu and colleagues at MIT discovered that magnesium might have a positive influence on learning and memory. “Half the population of the industrialized countries has a magnesium deficit, which increases with aging. If normal or even higher levels of magnesium can be maintained, we may be able to significantly slow age-related loss of cognitive function and perhaps prevent or treat diseases that affect cognitive function,” Liu said.
The new form of magnesium is a salt of l-threonic acid, a metabolite of vitamin C. Magnesium L-Threonate (MgT) is able to cross the blood-brain barrier, and so is much more effective at directly increasing levels of magnesium in the brain.
“We found that elevation of brain magnesium led to significant enhancement of spatial and associative memory in both young and aged rats,” said Liu, now director of the Center for Learning and Memory at Tsinghua University. “If MgT is shown to be safe and effective in humans, these results may have a significant impact on public health.” Liu is cofounder of Magceutics, a California-based company developing drugs for prevention and treatment of age-dependent memory decline and Alzheimer’s disease.
To understand the molecular mechanisms underlying this MgT-induced memory enhancement, the researchers studied the changes induced in functional and structural properties of synapses. They found that in young and aged rats, MgT increased plasticity among synapses, the connections among neurons, and boosted the density of synapses in the hippocampus, a critical brain region for learning and memory.
Susumu Tonegawa at MIT’s Picower Institute for Learning and Memory helped carry out the initial behavioral experiments that showed that magnesium boosted memory in aged rats. Min Zhou’s laboratory at the University of Toronto helped demonstrate the enhancement of synaptic plasticity in magnesium-treated rats.
The researchers stress the importance of magnesium in the prevention and potential treatment of aging-related declines in memory and cognitive performance, but I'm thinking this new type of magnesium supplement may be a simple, safe, and effective nootropic for young and healthy people as well. Swanson Vitamins is already selling capsules of Magnesium L-Threonate that may be worth a try. They're expensive, though, at $30 for a 20-day supply.
Okay, forgive me for being dense when it comes to basic inorganic chemistry or the blood brain barrier, but I thought ionic compounds disassociated in solution? I can understand how the ionization state of the cation would be relevant. But why would the blood brain barrier's permeability to magnesium be impacted by the permeability of the threonate anion? Couldn't you have some kind of ion exchange through the BBB independant of the anions involved? Does magnesium threonate dissociate much more readily than other forms of ionic magnesium?
I'm all about magnesium supplementation. (And threonate supplementation now.) I just don't quite track what's special about this particular pairing.
Good question -- I'm not an expert on the topic either, but I'm imagining that normal magnesium supplementation results in the body binding the mag to its own preferred carrier, which may not make it through the BBB as often as MagT. Just a guess though.