Changes

I take magnesium for three reasons - migraines, endurance and bone health. Magnesium is vital to life, being part of every cell<ref name="a6"/>. It is even a critical part of energy supply, being needed for ATP usage. I believe it is a critical micronutrient for runners.

Only 32% of the US population gets their RDA of magnesium, and only 27% in NC [7]. <ref name="a7"/> Magnesium levels in the blood fall after a marathon, which suggests that runners are more at risk for magnesium deficiency than sedentary people. There is even some suggestion <ref name="a5"/> that magnesium deficiency is related to the death of a marathon runner due to mitral valve prolapse. [5]

There is some evidence for magnesium supplementation for improving athletic performance. "That means that athletes wouldn't be able to work or train as long as they would if they had better magnesium levels" [4]<ref name="a4"/>. There is evidence that magnesium deficiency can result in a significant reduction in exercise performance [9]<ref name="a9"/>. There is increased loss of magnesium in athletes [8] <ref name="a8"/> through sweat and urine. It seems a reasonable assumption to this author that the increased sweating that occurs in an NC summer would exacerbate this loss.

Magnesium is a critical component of bones, making up about 1% of the structure. Lower levels of magnesium produce, more brittle bones with larger bone crystals [1]<ref name="a1"/>. Inadequate magnesium results in lower blood calcium levels, resistance to hormone that control bone density and reduction of vitamin D effect; all result in reduced bone density [1]<ref name="a1"/>. There is some evidence that magnesium supplementation on its own will help bone density [10]<ref name="a10"/>. One study showed this in healthy older white subject, but not in black subjects [11]<ref name="a11"/>. Magnesium is also believed to be critical to calcium absorption [15]<ref name="a15"/>. (If you have concerns over bone density, don't forget to make sure you are getting enough Vitamin D.)

There is evidence for magnesium supplementation helping prevent migraines [2,3]<ref name="a2"/><ref name="a3"/>. Personally I have seen a reduction in my migraines, and an improvement in my low light vision. If you suffer from migraines, I would strongly recommend reading the reference articles.

There is some very tenuous evidence that magnesium can help with muscle cramps [12]<ref name="a12"/>. This is not a problem I suffer from, so I have no personal perspective.

There are studies that have linked magnesium deficiency with asthma, emphysema, Attention deficit/hyperactivity disorder (ADHD), Depression, type 2 diabetes, heart disease, high blood pressure in women, and several other problems. [1, 16]<ref name="a1"/><ref name="a16"/>

Magnesium, is absorbed at about 30-40% efficiency [13]<ref name="a13"/>. Good sources of magnesium in food include nuts, cereals, coffee, green leafy vegetables and especially chocolate [13]<ref name="a13"/>. Cheap supplements use magnesium oxide, which is very hard to absorb; I use magnesium orotate, though chelated forms are also supposed to work well. Avoid taking Magnesium sulfate as it is used to treat constipation [14]<ref name="a14"/>. Vitamin C can help absorption of minerals. Therefore I take magnesium with Vitamin C on an empty stomach. (Bathing in Epson Salts can also raise magnesium levels in the blood.)

I buy my Magnesium Orotate from Lucky Vitamin as they seem to have the best price I have found - [http://www.luckyvitamin.com/item/itemKey/55469. http://www.luckyvitamin.com/item/itemKey/55469.] I generally take one tablet (500mg) with Vitamin C on rising, and another post run.

== References - Magnesium ==[1] <references><ref name="a1"> Linus Pauling Institute - Magnesium[http:://lpi.oregonstate.edu/infocenter/minerals/magnesium/ http://lpi.oregonstate.edu/infocenter/minerals/magnesium/]</ref> [6]<ref name="a6">Magnesium deficiency (medicine)[http:://en.wikipedia.org/wiki/Magnesium_deficiency_%28medicine%29 http://en.wikipedia.org/wiki/Magnesium_deficiency_%28medicine%29]</ref> [7] <ref name="a7"> USDA intake figures for NC[http:://www.ars.usda.gov/Services/docs.htm?docid=11198 http://www.ars.usda.gov/Services/docs.htm?docid=11198]</ref> [13] <ref name="a13"> Magnesium in biology[http:://en.wikipedia.org/wiki/Magnesium_in_biology http://en.wikipedia.org/wiki/Magnesium_in_biology]</ref> [14] <ref name="a14"> Epsom Salts[http:://en.wikipedia.org/wiki/Epsom_salts http://en.wikipedia.org/wiki/Epsom_salts]</ref> [16]<ref name="a16">University of Maryland Medical Center - Magnesium[http:://www.umm.edu/altmed/articles/magnesium-000313.htm http://www.umm.edu/altmed/articles/magnesium-000313.htm]</ref> =<ref name= References - Magnesium and bones ==[10]"a10">Magnesium supplementation and osteoporosis[http:://www.ncbi.nlm.nih.gov/pubmed/7770187?dopt=Abstract http://www.ncbi.nlm.nih.gov/pubmed/7770187?dopt=Abstract]</ref> [11]<ref name="a11">Magnesium intake from food and supplements is associated with bone mineral density in healthy older white subjects.[http:://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=16274367 http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=16274367]</ref> [15] <ref name="a15"> Magnesium: A Key to Calcium Absorption[http:://www.mgwater.com/calmagab.shtml http://www.mgwater.com/calmagab.shtml] </ref><ref name== References - Magnesium and Migraines ==[2] "a2"> Magnesium Treatment for Migraines An Inexpensive but Equivocal Treatment[http:://neurologicalillness.suite101.com/article.cfm/magnesium_treatment_for_migraines http://neurologicalillness.suite101.com/article.cfm/magnesium_treatment_for_migraines]</ref> [3]<ref name="a3">Are Migraine Headaches a Symptom of a Magnesium Deficiency?[http:://www.ctds.info/magnesium-migraine.html http://www.ctds.info/magnesium-migraine.html] </ref><ref name== References - Magnesium and endurance ==[4] "a4"> Lack Energy? Maybe It's Your Magnesium Level[http:://www.ars.usda.gov/is/AR/archive/may04/energy0504.htm?pf=1 http://www.ars.usda.gov/is/AR/archive/may04/energy0504.htm?pf=1]</ref> [5] <ref name="a5"> The dangers of magnesium deficiency in endurance athletes [http:://findarticles.com/p/articles/mi_m0FDL/is_4_14/ai_n24940334/ http://findarticles.com/p/articles/mi_m0FDL/is_4_14/ai_n24940334/]</ref> [8]<ref name="a8">Micronutrients (magnesium, zinc, and copper): are mineral supplements needed for athletes?[http:://www.ncbi.nlm.nih.gov/pubmed/7550259 http://www.ncbi.nlm.nih.gov/pubmed/7550259]</ref> [9] <ref name="a9"> Iron, zinc and magnesium nutrition and athletic performance.[http:://grande.nal.usda.gov/ibids/index.php?mode2=detail&origin=ibids_references&therow=268068 http://grande.nal.usda.gov/ibids/index.php?mode2=detail&origin=ibids_references&therow=268068]</ref> =<ref name= References - Magnesium and cramps ==[12] "a12"> Exertional Heat Cramps: Recovery and Return to Play[http:://www.sanfordhealth.org/ClassLibrary/Page/Images/files/ExertionalHeatCramps.pdf http://www.sanfordhealth.org/ClassLibrary/Page/Images/files/ExertionalHeatCramps.pdf]</ref></references>