Editing Magnesium (section)

== Biological roles ==
{{Main|Magnesium in biology|Magnesium (medical use)}}

===Mechanism of action===
The important interaction between [[phosphate]] and magnesium ions makes magnesium essential to the basic [[nucleic acid]] chemistry of all cells of all known living organisms. More than 300 [[enzyme]]s require magnesium ions for their catalytic action, including all enzymes using or synthesizing [[Adenosine triphosphate|ATP]] and those that use other [[nucleotides]] to synthesize [[DNA]] and [[RNA]]. The ATP molecule is normally found in a [[Chelation|chelate]] with a magnesium ion.<ref>
{{cite book
| first1=Andrea, M.P.
| last1=Romani
| chapter=Magnesium in Health and Disease
|editor=Astrid Sigel
|editor2=Helmut Sigel
|editor3=Roland K. O. Sigel
|title=Interrelations between Essential Metal Ions and Human Diseases
|series=Metal Ions in Life Sciences
|volume=13
|date=2013
|publisher=Springer
|pages=49–79
|doi=10.1007/978-94-007-7500-8_3
| pmid=24470089
| isbn=978-94-007-7499-5
}}
</ref>

=== Nutrition ===
====Diet====
[[File:FoodSourcesOfMagnesium.jpg|thumb|alt=refer to caption; follow link for complete description|Examples of food sources of magnesium (clockwise from top left): bran muffins, pumpkin seeds, barley, buckwheat flour, low-fat vanilla yogurt, trail mix, halibut steaks, garbanzo beans, lima beans, soybeans, and spinach]] 
Spices, nuts, cereals, cocoa and vegetables are good sources of magnesium.<ref name="nih">{{cite web|url = http://ods.od.nih.gov/factsheets/magnesium/|title = Dietary Supplement Fact Sheet: Magnesium| publisher = Office of Dietary Supplements, US National Institutes of Health|date=11 February 2016|access-date=13 October 2016}}</ref> Green leafy vegetables such as spinach are also rich in magnesium.<ref name="mlp">{{cite web | url=https://medlineplus.gov/ency/article/002423.htm | title=Magnesium in diet | publisher=MedlinePlus, U.S. National Library of Medicine, National Institutes of Health | date=2 February 2016 | access-date=13 October 2016}}</ref>

====Dietary recommendations ====
In the [[United Kingdom|UK]], the recommended daily values by the [[Dietary Reference Intake]] for magnesium are {{val|300|u=mg}} for men and {{val|270|u=mg}} for women.<ref>{{cite web |url=http://www.nhs.uk/Conditions/vitamins-minerals/Pages/Other-vitamins-minerals.aspx |title=Vitamins and minerals – Others – NHS Choices |publisher=Nhs.uk |date=26 November 2012 |access-date=19 September 2013 |archive-date=7 April 2011 |archive-url=https://web.archive.org/web/20110407015806/http://www.nhs.uk/Conditions/vitamins-minerals/Pages/Other-vitamins-minerals.aspx |url-status=dead }}</ref> 

In the U.S. the [[Recommended Dietary Allowances]] (RDAs) are {{val|400|u=mg}} for men ages 19–30 and {{val|420|u=mg}} for older; for women {{val|310|u=mg}} for ages 19–30 and {{val|320|u=mg}} for older.<ref>{{cite book |chapter-url=https://www.ncbi.nlm.nih.gov/books/NBK109816/ |chapter=6, Magnesium |pages=190–249 |title=Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride |publisher=National Academy Press |year=1997}}</ref>

====Supplementation====
Numerous [[Magnesium (pharmaceutical preparation)|pharmaceutical preparations of magnesium]] and [[dietary supplement]]s are available. In two human trials magnesium oxide, one of the most common forms in magnesium dietary supplements because of its high magnesium content per weight, was less bioavailable than [[magnesium citrate]], chloride, lactate or aspartate.<ref name="Firoz2001">{{cite journal |author=Firoz M|author2=Graber M |title=Bioavailability of US commercial magnesium preparations |journal=Magnes Res |volume=14 |issue=4 |pages=257–262 |date=2001 |pmid=11794633}}</ref><ref name="Lindberg1990">{{cite journal |author=Lindberg JS|author2=Zobitz MM|author3=Poindexter JR|author4=Pak CY |title=Magnesium bioavailability from magnesium citrate and magnesium oxide |journal=J Am Coll Nutr |volume=9 |issue=1 |pages=48–55 |date=1990|pmid=2407766 |doi=10.1080/07315724.1990.10720349}}</ref>

===Metabolism===
An adult body contains {{val|22|–|26|u=grams}} of magnesium,<ref name="nih" /><ref>{{cite journal | pmid = 10727669 | volume=294 | title=Magnesium. An update on physiological, clinical and analytical aspects | date=April 2000 | pages=1–26 |issue=1–2 |vauthors=Saris NE, Mervaala E, Karppanen H, Khawaja JA, Lewenstam A |journal=Clin Chim Acta| doi=10.1016/S0009-8981(99)00258-2 }}</ref> with 60% in the [[skeleton]], 39% intracellular (20% in skeletal muscle), and 1% extracellular.<ref name="nih" /> Serum levels are typically {{val|0.7|–|1.0|u=mmol/L}} or {{val|1.8|–|2.4|u= [[Equivalent (chemistry)|mEq]]/L}}. Serum magnesium levels may be normal even when intracellular magnesium is deficient. The mechanisms for maintaining the magnesium level in the serum are varying [[Gastrointestinal tract|gastrointestinal]] absorption and [[renal]] excretion. Intracellular magnesium is correlated with intracellular [[potassium]]. Increased magnesium lowers [[calcium]]<ref name="ummedu">{{cite web|url=http://umm.edu/health/medical/altmed/supplement/magnesium|archive-url=https://web.archive.org/web/20170216071418/http://umm.edu/health/medical/altmed/supplement/magnesium|url-status=dead|archive-date=16 February 2017|title=Magnesium |publisher= University of Maryland Medical Center |website=Umm.edu |date=7 May 2013 |access-date=19 September 2013}}</ref> and can either prevent hypercalcemia or cause hypocalcemia depending on the initial level.<ref name="ummedu" /> Both low and high protein intake conditions inhibit magnesium absorption, as does the amount of [[phosphate]], [[phytate]], and [[fat]] in the gut. Unabsorbed dietary magnesium is excreted in feces; absorbed magnesium is excreted in urine and sweat.<ref name="Wester1987">{{cite journal |author=Wester PO |title=Magnesium |journal=Am. J. Clin. Nutr. |volume=45 |issue=5 Suppl |pages=1305–1312 |date=1987 |pmid=3578120|doi=10.1093/ajcn/45.5.1305 }}</ref>

=== Detection in serum and plasma ===
Magnesium status may be assessed by measuring serum and erythrocyte magnesium concentrations coupled with [[Urinary system|urinary]] and [[Feces|fecal]] magnesium content, but intravenous magnesium loading tests are more accurate and practical.<ref>{{cite journal |author=Arnaud MJ |title=Update on the assessment of magnesium status |journal=Br. J. Nutr. |volume=99 |pages=S24–S36 |date=2008|issue=Suppl 3 |pmid=18598586 |doi=10.1017/S000711450800682X |doi-access=free }}</ref> A retention of 20% or more of the injected amount indicates deficiency.<ref>{{cite journal |display-authors=6|author=Rob PM|author2=Dick K|author3=Bley N|author4=Seyfert T|author5=Brinckmann C|author6=Höllriegel V|author7=Friedrich HJ|author8=Dibbelt L|author9=Seelig MS|title=Can one really measure magnesium deficiency using the short-term magnesium loading test? |journal=J. Intern. Med. |volume=246 |issue=4 |pages=373–378 |date=1999 |pmid=10583708 |doi= 10.1046/j.1365-2796.1999.00580.x |s2cid=6734801|doi-access=free}}</ref> As of 2004, no [[biomarker]] has been established for magnesium.<ref>{{cite journal |author=Franz KB |title=A functional biological marker is needed for diagnosing magnesium deficiency |journal=J Am Coll Nutr |volume=23 |issue=6 |pages=738S–741S |date=2004|pmid=15637224 |doi=10.1080/07315724.2004.10719418|s2cid=37427458 }}</ref>

Magnesium concentrations in plasma or serum may be monitored for efficacy and safety in those receiving the drug [[Therapy|therapeutically]], to confirm the diagnosis in potential poisoning victims. The newborn children of mothers who received [[Parenteral nutrition|parenteral]] magnesium sulfate during labor may exhibit toxicity with normal serum magnesium levels.<ref>{{cite book |author=Baselt, R. |title=Disposition of Toxic Drugs and Chemicals in Man |publisher=Biomedical Publications |edition=8th |year=2008 |isbn=978-0962652370 |pages=875–877 }}</ref>

===Deficiency===
Low plasma magnesium ([[hypomagnesemia]]) is common: it is found in 2.5–15% of the general population.<ref name="Ayuk">{{cite journal |author1=Ayuk J. |author2=Gittoes N.J. | date = Mar 2014 | title = Contemporary view of the clinical relevance of magnesium homeostasis | journal = Annals of Clinical Biochemistry | volume = 51 | issue = 2| pages = 179–188 | doi = 10.1177/0004563213517628 |pmid=24402002 |s2cid=21441840 | doi-access = free }}</ref> From 2005 to 2006, 48 percent of the United States population consumed less magnesium than recommended in the [[Dietary Reference Intake]].<ref>{{cite journal |last1=Rosanoff |first1=Andrea |last2=Weaver |first2=Connie M |last3=Rude |first3=Robert K |title=Suboptimal magnesium status in the United States: are the health consequences underestimated? |journal=Nutrition Reviews |date=March 2012 |volume=70 |issue=3 |pages=153–164 |doi=10.1111/j.1753-4887.2011.00465.x |pmid=22364157 |url=http://www.nutritionalmagnesium.org/images/stories/pdf/Suboptimalmagnesium.pdf}}</ref> Other causes are increased renal or gastrointestinal loss, an increased intracellular shift, and proton-pump inhibitor antacid therapy. Most are asymptomatic, but symptoms referable to [[Neuromuscular medicine|neuromuscular]], [[Circulatory system|cardiovascular]], and metabolic dysfunction may occur.<ref name="Ayuk" /> [[Alcoholism]] is often associated with magnesium deficiency. Chronically low serum magnesium levels are associated with [[metabolic syndrome]], [[diabetes mellitus type 2]], [[fasciculation]], and hypertension.<ref name="Geiger2012">{{cite journal |author= Geiger H|author2= Wanner C |title= Magnesium in disease |journal= Clin Kidney J |volume=5 |issue= Suppl 1 |pages= i25–i38 |date=2012|doi= 10.1093/ndtplus/sfr165|pmid= 26069818 |pmc= 4455821 }}</ref>

===Therapy===
* Intravenous magnesium is recommended by the ACC/AHA/ESC 2006 Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death for patients with ventricular [[Heart arrhythmia|arrhythmia]] associated with [[torsades de pointes]] who present with [[long QT syndrome]]; and for the treatment of patients with digoxin induced arrhythmias.<ref name="Zipes2006">{{cite journal |author= Zipes DP|author2= Camm AJ|author3= Borggrefe M|display-authors= etal |title= ACC/AHA/ESC 2006 Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death: a report of the American College of Cardiology/American Heart Association Task Force and the European Society of Cardiology Committee for Practice Guidelines (writing committee to develop Guidelines for Management of Patients With Ventricular Arrhythmias and the Prevention of Sudden Cardiac Death): developed in collaboration with the European Heart Rhythm Association and the Heart Rhythm Society |journal= Circulation |volume=114 |pages= e385–e484|date=2012 |doi= 10.1161/CIRCULATIONAHA.106.178233 |issue= 10 |pmid=16935995|doi-access= free }}</ref>
* Intravenous magnesium sulfate is used for the management of [[pre-eclampsia]] and [[eclampsia]].<ref name="James2010">{{cite journal |author= James MF |title= Magnesium in obstetrics |journal= Best Pract Res Clin Obstet Gynaecol |volume=24 |pages=327–337|date=2010 |doi=10.1016/j.bpobgyn.2009.11.004 |pmid= 20005782 |issue= 3}}</ref><ref name="Euser2009">{{Cite journal | last1 = Euser | first1 = A. G. | last2 = Cipolla | first2 = M. J. | doi = 10.1161/STROKEAHA.108.527788 | title = Magnesium Sulfate for the Treatment of Eclampsia: A Brief Review | journal = Stroke | volume = 40 | issue = 4 | pages = 1169–1175 | year = 2009 | pmid = 19211496| pmc =2663594 }}</ref>
* Hypomagnesemia, including that caused by alcoholism, is reversible by oral or parenteral magnesium administration depending on the degree of deficiency.<ref>{{cite book|author=Giannini, A. J.|title=Drugs of Abuse|edition=Second|location=Los Angeles|publisher=Physicians Management Information Co.|date=1997|isbn=978-0874894998}}</ref>
* There is limited evidence that magnesium supplementation may play a role in the prevention and treatment of [[migraine]].<ref name="migraine">{{cite journal |vauthors=Teigen L, Boes CJ |title=An evidence-based review of oral magnesium supplementation in the preventive treatment of migraine |journal=Cephalalgia |volume= 35|issue= 10|pages= 912–922|year=2014 |pmid=25533715 |doi=10.1177/0333102414564891 |s2cid=25398410 |type=Review |quote=There is a strong body of evidence demonstrating a relationship between magnesium status and migraine. Magnesium likely plays a role in migraine development at a biochemical level, but the role of oral magnesium supplementation in migraine prophylaxis and treatment remains to be fully elucidated. The strength of evidence supporting oral magnesium supplementation is limited at this time. }}</ref>

====Other medical applications====

Sorted by type of magnesium salt, other therapeutic applications include:

* [[Magnesium sulfate]], as the [[hydrate|heptahydrate]], also known as [[epsom salts]] from its source mineral, is used as bath salts, a laxative, and a highly soluble fertilizer.<ref>{{cite book | url = https://books.google.com/books?id=GP1caeWDUWkC&pg=PA224 | page=224 | title = The Fertilizer Encyclopedia | isbn = 978-0470431764 | last1 = Gowariker | first1 = Vasant | last2 = Krishnamurthy |first2=V. P. |first3=Sudha |last3=Gowariker |first4=Manik |last4=Dhanorkar |first5=Kalyani |last5=Paranjape | date = 8 April 2009| publisher=John Wiley & Sons }}</ref>
* [[Magnesium hydroxide]], suspended in water, is used in [[milk of magnesia]] antacids and laxatives.
* [[Magnesium chloride]], [[magnesium oxide|oxide]], [[magnesium gluconate|gluconate]], [[magnesium malate|malate]], [[magnesium orotate|orotate]], [[Magnesium glycinate|glycinate]], [[magnesium ascorbate|ascorbate]] and [[magnesium citrate|citrate]] are all used as oral magnesium supplements. 
* Magnesium borate, [[magnesium salicylate|salicylate]], and [[magnesium sulfate|sulfate]] are used as [[antiseptic]]s.
* [[Magnesium stearate]] is a slightly flammable white powder with lubricating properties. In [[pharmacology|pharmaceutical]] technology, it is used in pharmacological manufacture to prevent [[Tablet (pharmacy)|tablets]] from sticking to the equipment while compressing the ingredients into tablet form.
* [[Magnesium carbonate]] powder is used by athletes such as gymnasts, weightlifters, and climbers to eliminate palm sweat, prevent sticking, and improve the grip on gymnastic apparatus, lifting bars, and climbing rocks.

===Overdose===
Overdose from dietary sources alone is unlikely because excess magnesium in the blood is promptly filtered by the [[kidney]]s. Overdose is more likely in the presence of impaired renal function.<ref name="Ayuk" />  Overdose is likely in cases of excessive intake of supplements. [[Megavitamin therapy]] has caused death in a child,<ref>{{cite journal |last1=McGuire |first1=John K. |last2=Kulkarni |first2=Mona Shah |last3=Baden |first3=Harris P. |title=Fatal Hypermagnesemia in a Child Treated with Megavitamin/Megamineral Therapy |journal=Pediatrics |date=1 February 2000 |volume=105 |issue=2 |pages=e18 |doi=10.1542/peds.105.2.e18 |pmid=10654978 }}</ref> and severe [[hypermagnesemia]] in a woman and a young girl who had healthy kidneys.<ref name="Kontani M, Hara A, Ohta S, Ikeda T 2005 448–452">{{cite journal |author=Kontani M|author2=Hara A|author3=Ohta S|author4= Ikeda T |title=Hypermagnesemia induced by massive cathartic ingestion in an elderly woman without pre-existing renal dysfunction |journal=Intern. Med. |volume=44 |issue=5 |pages=448–452 |date=2005 |pmid=15942092| doi = 10.2169/internalmedicine.44.448|doi-access=free |hdl=2297/16751 |hdl-access=free }}</ref><ref>{{cite journal|last1=Kutsal|first1=Ebru|last2=Aydemir|first2=Cumhur|last3=Eldes|first3=Nilufer|last4=Demirel|first4=Fatma|last5=Polat|first5=Recep|last6=Taspınar|first6=Ozan|last7=Kulah|first7=Eyup|title=Severe Hypermagnesemia as a Result of Excessive Cathartic Ingestion in a Child Without Renal Failure|journal=Pediatrics|date=February 2000|volume=205|issue=2|pages=570–572|doi=10.1097/PEC.0b013e31812eef1c|pmid=17726419}}</ref> The most common symptoms of overdose are nausea, vomiting, and diarrhea; other symptoms include [[hypotension]], confusion, slowed heart and [[Respiratory system|respiratory]] rates, deficiencies of other minerals, [[coma]], [[Cardiac arrhythmia/bradycardia|cardiac arrhythmia]], and death from [[cardiac arrest]].<ref name="ummedu" />

===Function in plants===
Plants require magnesium to synthesize [[chlorophyll]], essential for [[photosynthesis]].<ref>{{Cite web |title=Magnesium |url=https://www.tfi.org/sites/default/files/tfi-magnesium.pdf |access-date=14 July 2023 |publisher=The Fertilizer Institute |archive-date=18 March 2023 |archive-url=https://web.archive.org/web/20230318010641/https://www.tfi.org/sites/default/files/tfi-magnesium.pdf |url-status=dead }}</ref> Magnesium in the center of the [[porphyrin ring]] in chlorophyll functions in a manner similar to the iron in the center of the porphyrin ring in [[heme]]. [[Magnesium deficiency (plants)|Magnesium deficiency]] in plants causes late-season yellowing between leaf veins,<ref>{{Cite web |date=2023-06-12 |title=What Is the Connection between Chlorophyll and Magnesium? |url=http://www.allthingsnature.org/what-is-the-connection-between-chlorophyll-and-magnesium.htm |access-date=2023-07-14 |website=All Things Nature |language=en-US}}</ref> especially in older leaves, and can be corrected by either applying epsom salts (which is rapidly leached), or crushed dolomitic limestone, to the soil.