Cognitive Supplement Spotlight: Magnesium Threonate


This is the first in a regular series on supplements which have been shown, through research and/or traditional use, to support cognitive function.  These supplements, along with prescription medications and other substances, are called nootropics.  As more and more Americans age and face challenges with memory and mental processing, we are looking for “magic pills” to build up our brainpower and help us keep sharp.


While no one pill can solve aging and reverse cognitive decline, many have been shown to help.  I hope to provide commonsense, realistic recommendations for the products I will be reviewing.


Please note that none of these recommendations is meant to replace my basic recommendation of regular exercise (5 times a week, minimum of 30 minutes aerobic plus 15 minutes’ strength training three times a week) and a brain-friendly diet (Ketoflex 12/3 is ideal – contact the office for more info on this), in addition to the ultimate nootropic, sleep.


Magnesium Threonate — Labeled as:  Neuro-Mag, Magtein. 

What is it?



Developed by MIT researchers, this version of magnesium has been shown to cross the blood brain barrier more effectively than any other.  By combining magnesium with threonine, an essential amino acid, these scientists solved the problem of getting magnesium from the blood into the brain.  Previously, the only remotely effective way was through intravenous delivery.


Why is magnesium important for the brain?

           Magnesium is essential for activating enzymes, regulating calcium levels in the cell, forming synapses, breaking down amyloid plaque, and other activities.  Studies have shown that people with Alzheimer’s disease have lower cerebrospinal levels of magnesium.


Magnesium helps to sensitize cells to the effect of insulin, cutting down on sugar in the blood and reducing inflammation.  Magnesium help us relax, supporting healthy sleep and reducing stress.  All of these effects help keep our brains healthier.






What is the evidence for Magnesium Threonate?


The early research on this product showed that it increased the number of synapses in the brain, repaired damaged synapses, raised brain magnesium levels more effectively than other forms of magnesium, improved function in the hippocampus (the memory area) and, most importantly, improved short-term memory (Li et al. Molecular Brain 2014, 7:65).


More recent research has shown improvement in brain circulation and cognitive testing in a small sample of people taking the supplement for 12 weeks (Innovation in Aging, Volume 1, Issue suppl_1, 1 July 2017, Pages 170).


What are the side-effects and dosage?

             Too much magnesium will cause loose stools.  For most of us, that is over 200 mg a day.  Some people can tolerate over 500 mg of supplemental magnesium with no problems.  The recommended dose of Mag Threonate is 144 mg of elemental (pure) magnesium a day, delivered in three capsules of Mag Threonate.  You can take two in the morning, and one at night.

Some people get a little drowsy in the beginning, others notice an increased sensation of blood flow in the head, while others may get mild headaches.  T


Can/Should I take this with my other magnesium supplements?

                       If you are taking magnesium for constipation, you may want to try continuing your current dose while adding the Mg Threonate.  If you develop loose stools, cut back on your previous form of Mg.


How long before I notice any benefit?

             Wait at least a month.  I would give it 8 weeks.


Does Dr. Goodman have a preferred brand or form that he offers?

             All the commercial brands use the patented Magtein form. is the manufacturer’s site and sells directly to the consumer. Make sure the label indicates it is Magtein.