Your mother was right – eating your “greens” (which contain magnesium) is good for you. In fact, according to neuroscientists at MIT and Tsinghua University in Beijing, rats who were fed a new compound that increased their brain magnesium demonstrated enhanced learning abilities, working memory, and short- and long-term memory. The dietary supplement also boosted older rats’ ability to perform a variety of learning tests. Great, if it’s not hard enough getting rid of the rodents now, imagine trying to remove smarter rats!

Magnesium, an essential element, “hides” in dark, leafy vegetables such as spinach and some fruits. Health professionals say people who get less than 400mg a day are risking allergies, asthma and heart disease, and possibly other conditions. In 2004, Guosong Liu and colleagues at MIT discovered that magnesium might also have a positive influence on learning and memory. They developed a new magnesium compound — magnesium-L-threonate (MgT) — that they say is more effective than conventional oral supplements at boosting magnesium in the brain. They then tried it out on lab rats.

“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 a co-founder of California-based company, Magceutics, that develops drugs for prevention and treatment of age-dependent memory decline and Alzheimer’s disease.

“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 researchers found that MgT increased the plasticity in connections among neurons, called synapses, in young and old rats. They also found that after increased levels of MgT were introduced to the rats, the density of synapses increased in the hippocampus, a critical brain region for learning and memory.

This study not only highlights the importance of a diet with sufficient daily magnesium, but also suggests the usefulness of magnesium-based treatments for aging-associated memory decline, said Susumu Tonegawa at MIT’s Picower Institute for Learning and Memory, who helped carry out the initial behavioral experiments. Clinical studies in Beijing are now investigating the relationship between body magnesium status and cognitive functions in older humans and Alzheimer’s patients.