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Biological role

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Because of the important interaction between phosphate and magnesium ions, magnesium ions are essential to the basic nucleic acid chemistry of life, and thus are essential to all cells of all known living organisms. Over 300 enzymes require the presence of magnesium ions for their catalytic action, including all enzymes utilizing or synthesizing ATP, or those that use other nucleotides to synthesize DNA and RNA. ATP exists in cells normally as a chelate of ATP and a magnesium ion.

Plants have an additional use for magnesium in that chlorophylls are magnesium-centered porphyrins. Magnesium deficiency in plants causes late-season yellowing between leaf veins, especially in older leaves, and can be corrected by applying Epsom salts (which is rapidly leached), or else crushed dolomitic limestone to the soil.

Examples of food sources of magnesium

Magnesium is a vital component of a healthy human diet. Human magnesium deficiency (including conditions that show few overt symptoms) is relatively rare[1] although only 32% of the United States meet the RDA-DRI;[2] Link to recommended Magnesium intake low levels of magnesium in the body has been associated with the development of a number of human illnesses such as asthma, diabetes, and osteoporosis.[3] Taken in the proper amount magnesium also shows that plays a role in preventing both stroke and heart attack. The symptoms of people with fibromyalgia, migraines, and girls going through their premenstrual syndrome are less severe and in migraines magnesium can shorten the length of the migraine. Cite error: A <ref> tag is missing the closing </ref> (see the help page). Magnesium status may be assessed roughly through serum and erythrocyte Mg concentrations and urinary and fecal excretion, but intravenous magnesium loading tests are likely the most accurate and practical in most people.[4] In these tests, magnesium is injected intravenously; a retention of 20% or more indicates deficiency.[5] Other nutrient deficiencies are identified through biomarkers, but none are established for magnesium.[6]

Spices, nuts, cereals, coffee, cocoa, tea, and vegetables are rich sources of magnesium. Green leafy vegetables such as spinach are also rich in magnesium as they contain chlorophyll. Observations of reduced dietary magnesium intake in modern Western countries compared to earlier generations may be related to food refining and modern fertilizers that contain no magnesium.[7] Link to foods that are high in magnesium

Numerous magnesium dietary supplements are available. Magnesium oxide, one of the most common because it has high magnesium content per weight, has been reported to be the least bioavailable.[8][9] Magnesium citrate has been reported as more bioavailable than oxide or amino-acid chelate (glycinate) forms.[10]

Excess magnesium in the blood is freely filtered at the kidneys, and for this reason it is difficult to overdose on magnesium from dietary sources alone.[3] With supplements, overdose is possible, however, particularly in people with poor renal function; occasionally, with use of high cathartic doses of magnesium salts, severe hypermagnesemia has been reported to occur even without renal dysfunction.[11] Alcoholism can produce a magnesium deficiency, which is easily reversed by oral or parenteral administration, depending on the degree of deficiency.[12]

Detection in biological fluids

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Magnesium concentrations in plasma or serum may be measured to monitor for efficacy and safety in those receiving the drug therapeutically, to confirm the diagnosis in potential poisoning victims or to assist in the forensic investigation in a case of fatal overdosage. The newborn children of mothers who received parenteral magnesium sulfate during labor may exhibit toxicity at serum magnesium levels that were considered appropriate for the mothers.[13]

Magnesium in treatment-resistant depression (TRD)

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There has been some speculation that magnesium deficiency can lead to depression. Cerebral spinal fluid (CSF) magnesium has been found low in treatment-resistant suicidal depression and in patients that have attempted suicide. Brain magnesium has been found low in TRD using phosphorus nuclear magnetic resonance spectroscopy, an accurate means for measuring brain magnesium. Blood and CSF magnesium do not appear well-correlated with major depression.[14] Magnesium chloride in relatively small doses was found to be as effective in the treatment of depressed elderly type 2 diabetics with hypomagnesemia as imipramine 50 mg daily.[15]

  1. ^ "Magnesium". Ods.od.nih.gov. 2009-07-13. Retrieved 2011-11-04.
  2. ^ "Lack Energy? Maybe It's Your Magnesium Level". United States Department of Agriculture. Retrieved 2008-09-18. Last paragraph
  3. ^ a b University of Maryland Medical Center. Magnesium
  4. ^ Arnaud MJ (2008). "Update on the assessment of magnesium status". Br. J. Nutr. 99 Suppl 3: S24–36. doi:10.1017/S000711450800682X. PMID 18598586.
  5. ^ Rob PM; Dick K; Bley N; et al. (1999). "Can one really measure magnesium deficiency using the short-term magnesium loading test?". J. Intern. Med. 246 (4): 373–378. doi:10.1046/j.1365-2796.1999.00580.x. PMID 10583708. {{cite journal}}: Unknown parameter |author-separator= ignored (help)
  6. ^ Franz KB (2004). "A functional biological marker is needed for diagnosing magnesium deficiency". J Am Coll Nutr. 23 (6): 738S–41S. PMID 15637224.
  7. ^ Cite error: The named reference Wester1987 was invoked but never defined (see the help page).
  8. ^ Firoz M, Graber M (2001). "Bioavailability of US commercial magnesium preparations". Magnes Res. 14 (4): 257–62. PMID 11794633.
  9. ^ Lindberg JS, Zobitz MM, Poindexter JR, Pak CY (1990). "Magnesium bioavailability from magnesium citrate and magnesium oxide". J Am Coll Nutr. 9 (1): 48–55. PMID 2407766.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  10. ^ Walker AF, Marakis G, Christie S, Byng M (2003). "Mg citrate found more bioavailable than other Mg preparations in a randomised, double-blind study". Magnes Res. 16 (3): 183–91. PMID 14596323.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  11. ^ Kontani M, Hara A, Ohta S, Ikeda T (2005). "Hypermagnesemia induced by massive cathartic ingestion in an elderly woman without pre-existing renal dysfunction". Intern. Med. 44 (5): 448–452. doi:10.2169/internalmedicine.44.448. PMID 15942092.{{cite journal}}: CS1 maint: multiple names: authors list (link)
  12. ^ Giannini, A. J. (1997). Drugs of Abuse (Second ed.). Los Angeles: Physicians Management Information Co. ISBN 0874894999.
  13. ^ R. Baselt, Disposition of Toxic Drugs and Chemicals in Man, 8th edition, Biomedical Publications, Foster City, CA, 2008, ISBN 0962652377 pp. 875–877.
  14. ^ Eby Ga, 3rd; Eby, KL (2010). "Magnesium for treatment-resistant depression: a review and hypothesis" (PDF). Medical hypotheses. 74 (4): 649–660. doi:10.1016/j.mehy.2009.10.051. PMID 19944540.{{cite journal}}: CS1 maint: numeric names: authors list (link)
  15. ^ Barragán-Rodríguez, L; Rodríguez-Morán, M; Guerrero-Romero, F (2008). "Efficacy and safety of oral magnesium supplementation in the treatment of depression in the elderly with type 2 diabetes: a randomized, equivalent trial". Magnesium research : official organ of the International Society for the Development of Research on Magnesium. 21 (4): 218–23. PMID 19271419.