Magnesium is an essential dietary mineral, and the second most prevalent electrolyte in human cells. Magnesium has a diverse set of cognitive effects, including improvements in sleep, decreased stress, and increased attention.
Magnesium is essential for general health, as it helps to improve neural excitation, control blood pressure, and maintain glucose tolerance. Magnesium deficiencies are common in developed countries. Approximately 68% of adults in the US do not meet the recommended intake of magnesium, with 19% consuming less than half the recommended amount. Some degree of magnesium deficiency appears to affect a large percentage of adults. Magnesium deficiency is implicated in various disorders and diseases, namely attention deficit hyperactivity disorder.
Is it safe? Are there side effects?
Magnesium is classified as GRAS (generally regarded as safe) by the FDA.
There are no major side effects if magnesium is taken in safe quantities (less than 350mg per day). Certain cardiovascular effects such as heart block may occur due to magnesium toxicity. There is increased risk of bleeding especially in individuals predisposed to bleeding disorders (e.g. genetic conditions).1Additionally, there is a risk of pulmonary edema associated with abnormally high magnesium sulfate levels in pregnant women undergoing tocolysis.
Effects on Cognition
A study in 12 elderly people (aged 60-80) showed that taking 30 mmol Magnesium for 20 days, was effective in improving sleep. Those individuals that consumed the magnesium exhibited a significant increase in slow wave sleep. Cortisol, a marker for stress, decreased in those individuals as well.
A study on individuals ages 51 and older showed that supplementation of magnesium improved various markers of inflammatory stress, particular cortisol levels.
A study on 78 normal subjects aged 60 and over showed that magnesium pemoline administration did not result in changes in memory. Another study confirmed the same lack of facilitation with magnesium pemoline.
A study of female patients undergoing preterm labor, showed that magnesium sulfate had a positive effect on working memory as measured by the Paced Auditory Serial Addition Test.
A study in female patients undergoing preterm labor, showed that magnesium sulfate had a positive effect on attention as measured by the Paced Auditory Serial Addition Test.
A study on 78 normal subjects aged 60 and over showed that magnesium pemoline administration was associated with mildly increased depression rates.5
Effects on Medical Conditions
Studies in children with attention deficit hyperactivity disorder shed light on how we can improve cognitive function in normal humans.
A study on 116 children aged 9-12 years with ADHD showed that magnesium levels were lower than normal in over 95% of the ADHD patients. Thus, it is suggested that magnesium could be involved in treatment.
A study in 40 children with ADHD showed that administration of a magnesium-vitamin B6 hybrid supplement for 8 weeks was effective in decreasing the symptoms of ADHD. In particular, hyperactivity and hyperemotivity/aggressiveness were significantly ameliorated in children that took this supplement.
A study in ADD patients with concurrent cocaine abuse showed that administration of magnesium pemoline resulted in significantly decreased cocaine abuse.
It has been suggested in many studies that magnesium can lower the risk of various types of cancer.
Magnesium has been shown to decrease the risk of colon cancer. A study in Swedish women 55-69 years of age showed that supplementation of magnesium in the diet was correlated with lower rates of colon cancer in the future.
A retrospective study involving 161 patients showed that magnesium supplementation had been helpful in preventing the neurotoxicity normally associated with oxaliplatin, a chemotherapeutic drug for colorectal cancer. This finding was corroborated in a later study of 102 patients.
Structure & Synthesis
Magnesium can be obtained from various natural sources, including leafy green vegetables, nuts and seeds, fish, beans, lentils, avocados, bananas, fruits, and dark chocolate.
Magnesium bound to citrate appears to have a higher bioavailability at around 25-30%, probably due to its increased water solubility relative to oxide chelations.
Mechanisms of Action
Magnesium is used in the body primarily as an electrolyte and a mineral cofactor for over 300 enzymes. Most notably, it is involved in the enzyme systems for ATP and Adenyl Cyclase, and is required for the activation of creatine kinase and enzymes in the glycolysis pathway.
Magnesium is a modulator of glutaminergic neurotransmission associated with aging. This phenomenon has been documented in mouse studies, demonstrating a reduced reuptake of glutamate in aged animals compared to younger ones.
A large number of studies suggest that magnesium acts as an antagonist at NMDA receptors and an agonist at GABA receptors. Studies have observed that magnesium suppresses ACTH secretion nocturnally.