Magnesium and the Brain

Some interesting new research is coming out about one of the most common nutrient deficiencies and brain health. It’s estimated that about half of adults in the U.S. don’t get the recommended amount of magnesium in their diets and that may be having significant adverse effects on the structure and function of their brains.

Magnesium has long bee known as a major player in cardiovascular and muscular function, but it appears that it also plays a large role in the health of the brain. It used to be thought that magnesium did not cross the blood-brain barrier to a significant extent, and it is true that some forms of magnesium supplementation travel into the brain tissue more easily than others. But recent research shows that it not only enters the brain when sufficient levels are present in the blood, but magnesium plays a vital role in supporting brain tissue and in promoting connections between brain cells.

One recent study showed dramatically increased axon production in the brain in individuals with higher magnesium levels. Axons are the “wires” that connect brain cells and generally the more connections, the better.

What this means in terms of brain function is still controversial, but it appears that normal magnesium levels in the brain improves cognitive function and may help prevent dementia and other neurodegenerative disorders.

That said, it’s important to note that some research has shown that too much magnesium may also cause an increased risk of dementia. This is not an uncommon issue with various nutrients and various aspects of health, and it highlights the fact that while our bodies need these nutrients, mega-dosing with supplements can create abnormal biochemical and physiological effects, so moderation is important.

Excess magnesium also tends to cause loose stools for many people, so again, moderation is advised.

So, how much magnesium is recommended? The RDA for magnesium for adult men is 400 mg per day and for adult women, 320 mg per day. The RDA is kind of a mixed bag, with some daily intake recommendations probably being way too low, but for magnesium, those suggested dosages are probably pretty good for most people. Again, some research indicates risks from excess magnesium intake, so a moderate dose is probably best for getting good benefits without significant risks.

While there are several foods that are good sources of magnesium, including whole grains, leafy greens, legumes, and nuts, many people fail to get adequate magnesium from diet alone and supplementation is recommended unless you eat a really good well-balanced diet.

If your diet does consistently include some of the food sources listed above, you don’t need to supplement heavily, but maybe shoot for 50% to 75% of the RDA with supplements.

It’s important to note that the RDAs mentioned previously are for elemental magnesium. Different supplement forms will vary somewhat in the amount that elemental magnesium contributes to the total milligrams of the supplement. For example, 2000 mg of magnesium threonate only contains 144 mg of elemental magnesium, because the threonate portion of the molecule is fairly large.

For the brain specifically, the magnesium threonate form appears to be the best for actually crossing the blood-brain barrier and actually reaching the brain tissue. In addition to improved cognitive function, magnesium threonate is an effective sleep aid for many people as well. Unfortunately, this form is not as effective for cardiovascular and muscular effects and it somewhat more expensive than other forms. From a practicality standpoint (and to minimize the number of supplements to take), most people probably don’t need to use the threonate form, unless they find it helpful for sleep.

For general supplementation, I suggest going with one of the less expensive and more commonly available forms of magnesium (aspartate, glycinate, etc.) to help you reach the RDA. For most people, this will probably be sufficient for brain health as well as cardiovascular and muscular function.

Until next time…

George F. Best, D.C.