Magnesium deficiency

Magnesium deficiency is an electrolyte disturbance in which there is a low level of magnesium in the body. It can result in multiple symptoms.[3] Symptoms include tremor, poor coordination, muscle spasms, loss of appetite, personality changes, and nystagmus.[1][2] Complications may include seizures or cardiac arrest such as from torsade de pointes.[1] Those with low magnesium often have low potassium.[1]

Magnesium deficiency
Other namesHypomagnesia, hypomagnesemia
Magnesium
SpecialtyEndocrinology
SymptomsTremor, poor coordination, nystagmus, seizures[1]
ComplicationsSeizures, cardiac arrest (torsade de pointes), low potassium[1]
CausesAlcoholism, starvation, diarrhea, increased urinary loss, poor absorption from the intestines, certain medications[1][2]
Diagnostic methodBlood levels < 0.6 mmol/L (1.46 mg/dL)[1]
TreatmentMagnesium salts[2]
FrequencyRelatively common (hospitalized people)[2]

Causes include low dietary intake, alcoholism, diarrhea, increased urinary loss, poor absorption from the intestines, and diabetes mellitus.[1][4][5] A number of medications may also cause low magnesium, including proton pump inhibitors (PPIs) and furosemide.[2] The diagnosis is typically based on finding low blood magnesium levels (hypomagnesemia).[6] Normal magnesium levels are between 0.6 and 1.1 mmol/L (1.46–2.68 mg/dL) with levels less than 0.6 mmol/L (1.46 mg/dL) defining hypomagnesemia.[1] Specific electrocardiogram (ECG) changes may be seen.[1]

Treatment is with magnesium either by mouth or intravenously.[2] For those with severe symptoms, intravenous magnesium sulfate may be used.[1] Associated low potassium or low calcium should also be treated.[2] The condition is relatively common among people in hospitals.[2]

Signs and symptoms

Deficiency of magnesium can cause tiredness, generalized weakness, muscle cramps, abnormal heart rhythms, increased irritability of the nervous system with tremors, paresthesias, palpitations, low potassium levels in the blood, hypoparathyroidism which might result in low calcium levels in the blood, chondrocalcinosis, spasticity and tetany, migraines,[7] epileptic seizures,[8] basal ganglia calcifications[9] and in extreme and prolonged cases coma, intellectual disability or death.[10] Magnesium plays an important role in carbohydrate metabolism and its deficiency may worsen insulin resistance, a condition that often precedes diabetes, or may be a consequence of insulin resistance.[11]

People being treated on an intensive care unit (ICU) who have a low magnesium level may have a higher risk of requiring mechanical ventilation, and death.[12]

Causes

Magnesium deficiency may result from gastrointestinal or kidney causes. Gastrointestinal causes include low dietary intake of magnesium, reduced gastrointestinal absorption or increased gastrointestinal loss due to rapid gastrointestinal transits. Kidney causes involve increased excretion of magnesium. Poor dietary intake of magnesium has become an increasingly important factor many people consume diets high in refined foods such as white bread and polished rice which have been stripped of magnesium-rich plant fiber.[13]

Magnesium deficiency is not uncommon in hospitalized patients. Up to 12% of all people admitted to hospital, and as high as 60–65% of people in an intensive care unit, have hypomagnesemia.[14]

About 57% of the US population does not meet the US RDA for dietary intake of magnesium.[15] The kidneys are very efficient at maintaining body levels; however, if the diet is deficient, or certain medications such as diuretics or proton pump inhibitors are used,[16] or in chronic alcoholism,[17] levels may drop.

Low levels of magnesium in blood may be due to not enough magnesium in the diet, the intestines not absorbing enough magnesium, or the kidneys excreting too much magnesium. Deficiencies may be due to the following conditions:

Medications

Genetics

Metabolic abnormalities

Other

Pathophysiology

Magnesium is a co-factor in over 300 functions in the body regulating many kinds of biochemical reactions.[22] It is involved in protein synthesis, muscle and nerve functioning, bone development, energy production, the maintenance of normal heart rhythm, and the regulation of glucose and blood pressure, among other important roles.[17] Low magnesium intake over time can increase the risk of illnesses, including high blood pressure and heart disease, diabetes mellitus type 2, osteoporosis, and migraines.[17]

There is a direct effect on sodium (Na), potassium (K), and calcium (Ca) channels. Magnesium has several effects:

Potassium

Potassium channel efflux is inhibited by magnesium. Thus hypomagnesemia results in an increased excretion of potassium in kidney, resulting in a hypokalaemia. This condition is believed to occur secondary to the decreased normal physiologic magnesium inhibition of the ROMK channels in the apical tubular membrane.[32]

In this light, hypomagnesemia is frequently the cause of hypokalaemic patients failing to respond to potassium supplementation. Thus, clinicians should ensure that both magnesium and potassium is replaced when deficient. Patients with diabetic ketoacidosis should have their magnesium levels monitored to ensure that the serum loss of potassium, which is driven intracellularly by insulin administration, is not exacerbated by additional urinary losses.

Calcium

Release of calcium from the sarcoplasmic reticulum is inhibited by magnesium. Thus hypomagnesemia results in an increased intracellular calcium level. This inhibits the release of parathyroid hormone, which can result in hypoparathyroidism and hypocalcemia. Furthermore, it makes skeletal and muscle receptors less sensitive to parathyroid hormone.[33]

Arrhythmia

Magnesium is needed for the adequate function of the Na+/K+-ATPase pumps in cardiac myocytes, the muscles cells of the heart. A lack of magnesium inhibits reuptake of potassium, causing a decrease in intracellular potassium. This decrease in intracellular potassium results in a tachycardia.

Pre-eclampsia

Magnesium has an indirect antithrombotic effect upon platelets and endothelial function. Magnesium increases prostaglandins, decreases thromboxane, and decreases angiotensin II, microvascular leakage, and vasospasm through its function similar to calcium channel blockers. Convulsions are the result of cerebral vasospasm. The vasodilatatory effect of magnesium seems to be the major mechanism.

Asthma

Magnesium exerts a bronchodilatatory effect, probably by antagonizing calcium-mediated bronchoconstriction.[34]

Neurological effects

  • reducing electrical excitation
  • modulating release of acetylcholine
  • antagonising N-methyl-D-aspartate (NMDA) glutamate receptors, an excitatory neurotransmitter of the central nervous system and thus providing neuroprotection from excitoxicity.

Diabetes mellitus

Magnesium deficiency is frequently observed in people with type 2 diabetes mellitus, with an estimated prevalence ranging between 11.0 and 47.7%.[35] Magnesium deficiency is strongly associated with high glucose and insulin resistance, which indicate that it is common in poorly controlled diabetes.[36] Patients with type 2 diabetes and a magnesium deficiency have a higher risk of heart failure, atrial fibrillation and microvascular complications.[37] Oral magnesium supplements has been demonstrated to improve insulin sensitivity and lipid profile.[38][39][40] A 2016 meta-analysis not restricted to diabetic subjects found that increasing dietary magnesium intake, while associated with a reduced risk of stroke, heart failure, diabetes, and all-cause mortality, was not clearly associated with lower risk of coronary heart disease (CHD) or total cardiovascular disease (CVD).[41]

A 2021 study on blood from 4,400 diabetic patients over 6 to 11 years reported that "People with higher levels of magnesium in the blood were found to have a significantly lower risk of cardiovascular disease", and also of diabetic foot and diabetic retinopathy. The researchers, however, stated that "we have [not] demonstrated that magnesium supplements work. Further research is needed."[42]

Homeostasis

Magnesium is abundant in nature. It can be found in green vegetables, chlorophyll (chloroplasts), cocoa derivatives, nuts, wheat, seafood, and meat. It is absorbed primarily in the duodenum of the small intestine. The rectum and sigmoid colon can absorb magnesium. Forty percent of dietary magnesium is absorbed. Hypomagnesemia stimulates and hypermagnesemia inhibits this absorption.

The body contains 21–28 grams of magnesium (0.864–1.152 mol). Of this, 53% is located in bone, 19% in non-muscular tissue, and 1% in extracellular fluid. For this reason, blood levels of magnesium are not an adequate means of establishing the total amount of available magnesium.

The majority of serum magnesium is bound to chelators, including proteins and citrate. Roughly 33% is bound to proteins, and 5–10% is not bound. This "free" magnesium is essential in regulating intracellular magnesium. Normal plasma Mg is 1.7–2.3 mg/dL (0.69–0.94 mmol/L).

The kidneys regulate the serum magnesium. About 2400 mg of magnesium passes through the kidneys daily, of which 5% (120 mg) is excreted through urine. The loop of Henle is the major site for magnesium homeostasis, and 60% is reabsorbed.

Magnesium homeostasis comprises three systems: kidney, small intestine, and bone. In the acute phase of magnesium deficiency there is an increase in absorption in the distal small intestine and tubular resorption in the kidneys. When this condition persists, serum magnesium drops and is corrected with magnesium from bone tissue. The level of intracellular magnesium is controlled through the reservoir in bone tissue.

Diagnosis

Magnesium deficiency or depletion is a low total body level of magnesium; it is not easy to measure directly.[43] Typically the diagnosis is based on finding hypomagnesemia, a low blood magnesium level,[44] which often reflects low body magnesium;[6] however, magnesium deficiency can be present without hypomagnesemia, and vice versa.[43] A plasma magnesium concentration of less than 0.6 mmol/L (1.46 mg/dL) is considered to be hypomagnesemia;[1] severe disease generally has a level of less than 0.50 mmol/L (1.25 mg/dL).[2]

Electrocardiogram

The electrocardiogram (ECG) change may show a tachycardia with a prolonged QT interval.[45] Other changes may include prolonged PR interval, ST segment depression, flipped T waves, and long QRS duration.[1]

Treatments

Treatment of magnesium deficiency depends on the degree of deficiency and the clinical effects. Replacement by mouth is appropriate for people with mild symptoms, while intravenous replacement is recommended for people with severe effects.[46]

Numerous oral magnesium preparations are available. In two trials of magnesium oxide, one of the most common forms in magnesium dietary supplements because of its high magnesium content per weight, was found to be less bioavailable than magnesium citrate, chloride, lactate or aspartate.[47][48] Amino-acid chelate was also less bioavailable.[49]

Intravenous magnesium sulfate (MgSO4) can be given in response to heart arrhythmias to correct for hypokalemia, preventing pre-eclampsia, and has been suggested as having a potential use in asthma.[1]

Food

Food sources of magnesium include leafy green vegetables, beans, nuts, and seeds.[50]

Epidemiology

The condition is relatively common among people in hospital.[2]

History

Magnesium deficiency in humans was first described in the medical literature in 1934.[51]

Plants

A plant with magnesium deficiency

Magnesium deficiency is a detrimental plant disorder that occurs most often in strongly acidic, light, sandy soils, where magnesium can be easily leached away. Magnesium is an essential macronutrient constituting 0.2-0.4% of plants' dry matter and is necessary for normal plant growth.[52] Excess potassium, generally due to fertilizers, further aggravates the stress from magnesium deficiency,[53] as does aluminium toxicity.[54]

Magnesium has an important role in photosynthesis because it forms the central atom of chlorophyll.[52] Therefore, without sufficient amounts of magnesium, plants begin to degrade the chlorophyll in the old leaves. This causes the main symptom of magnesium deficiency, interveinal chlorosis, or yellowing between leaf veins, which stay green, giving the leaves a marbled appearance. Due to magnesium's mobile nature, the plant will first break down chlorophyll in older leaves and transport the Mg to younger leaves which have greater photosynthetic needs. Therefore, the first sign of magnesium deficiency is the chlorosis of old leaves which progresses to the young leaves as the deficiency progresses.[55] Magnesium also acts as an activator for many critical enzymes, including ribulosebisphosphate carboxylase (RuBisCO) and phosphoenolpyruvate carboxylase (PEPC), both essential enzymes in carbon fixation. Thus low amounts of Mg lead to a decrease in photosynthetic and enzymatic activity within the plants. Magnesium is also crucial in stabilizing ribosome structures, hence, a lack of magnesium causes depolymerization of ribosomes leading to premature aging of the plant.[52] After prolonged magnesium deficiency, necrosis and dropping of older leaves occurs. Plants deficient in magnesium also produce smaller, woodier fruits.

Magnesium deficiency in plants may be confused with zinc or chlorine deficiencies, viruses, or natural aging, since all have similar symptoms. Adding Epsom salts (as a solution of 25 grams per liter or 4 oz per gal) or crushed dolomitic limestone to the soil can rectify magnesium deficiencies. An organic treatment is to apply compost mulch, which can prevent leaching during excessive rainfall and provide plants with sufficient amounts of nutrients, including magnesium.[56]

See also

References

  1. Soar J, Perkins GD, Abbas G, Alfonzo A, Barelli A, Bierens JJ, et al. (October 2010). "European Resuscitation Council Guidelines for Resuscitation 2010 Section 8. Cardiac arrest in special circumstances: Electrolyte abnormalities, poisoning, drowning, accidental hypothermia, hyperthermia, asthma, anaphylaxis, cardiac surgery, trauma, pregnancy, electrocution". Resuscitation. 81 (10): 1400–1433. doi:10.1016/j.resuscitation.2010.08.015. PMID 20956045.
  2. "Hypomagnesemia". Merck Manuals Professional Edition. Retrieved 27 October 2018.
  3. "Definition of Magnesium Deficiency". MedicineNet.com. Retrieved 31 May 2014.
  4. de Baaij JH, Hoenderop JG, Bindels RJ (January 2015). "Magnesium in man: implications for health and disease". Physiological Reviews. 95 (1): 1–46. CiteSeerX 10.1.1.668.9777. doi:10.1152/physrev.00012.2014. PMID 25540137.
  5. Gommers LM, Hoenderop JG, Bindels RJ, de Baaij JH (January 2016). "Hypomagnesemia in Type 2 Diabetes: A Vicious Circle?". Diabetes. 65 (1): 3–13. doi:10.2337/db15-1028. PMID 26696633.
  6. Goldman L, Schafer AI (2015). Goldman-Cecil Medicine E-Book. Elsevier Health Sciences. p. 775. ISBN 9780323322850.
  7. "Finding the Best Magnesium Supplements for Migraine". Migraine Again. 2021-04-26. Retrieved 2021-06-03.
  8. Yuen AW, Sander JW (June 2012). "Can magnesium supplementation reduce seizures in people with epilepsy? A hypothesis". Epilepsy Research. 100 (1–2): 152–156. doi:10.1016/j.eplepsyres.2012.02.004. PMID 22406257. S2CID 23147775.
  9. "Basal Ganglia Calcification with Hypomagnesemia". www.japi.org. Retrieved 2021-06-03.
  10. Viering DH, de Baaij JH, Walsh SB, Kleta R, Bockenhauer D (July 2017). "Genetic causes of hypomagnesemia, a clinical overview". Pediatric Nephrology. 32 (7): 1123–1135. doi:10.1007/s00467-016-3416-3. PMC 5440500. PMID 27234911.
  11. Kobrin SM, Goldfarb S (November 1990). "Magnesium deficiency". Seminars in Nephrology. 10 (6): 525–535. PMID 2255809.
  12. Upala S, Jaruvongvanich V, Wijarnpreecha K, Sanguankeo A (July 2016). "Hypomagnesemia and mortality in patients admitted to intensive care unit: a systematic review and meta-analysis". QJM. 109 (7): 453–459. doi:10.1093/qjmed/hcw048. PMID 27016536.
  13. DiNicolantonio JJ, O'Keefe JH, Wilson W (2018). "Subclinical magnesium deficiency: a principal driver of cardiovascular disease and a public health crisis". Open Heart. 5 (1): e000668. doi:10.1136/openhrt-2017-000668. PMC 5786912. PMID 29387426.
  14. Agus ZS (July 1999). "Hypomagnesemia". Journal of the American Society of Nephrology. 10 (7): 1616–1622. doi:10.1681/ASN.V1071616. PMID 10405219.
  15. "Nutrient Intakes Percent of population 2 years old and over with adequate intakes based on average requirement". Community Nutrition Mapping Project. 2009-07-29. Retrieved 2012-02-11.
  16. "FDA Drug Safety Communication: Low magnesium levels can be associated with long-term use of Proton Pump Inhibitor drugs (PPIs)". fda.gov. F.D.A. U.S. Food and Drug Administration. Retrieved 8 November 2014.
  17. "Magnesium: Fact Sheet for Health Professionals". nih.gov. National Institutes of Health. Retrieved 8 November 2014.
  18. Whang R, Hampton EM, Whang DD (February 1994). "Magnesium homeostasis and clinical disorders of magnesium deficiency". The Annals of Pharmacotherapy. 28 (2): 220–226. doi:10.1177/106002809402800213. PMID 8173141. S2CID 23442909.
  19. Gragossian A, Bashir K, Friede R (2021). "Hypomagnesemia". StatPearls. Treasure Island (FL): StatPearls Publishing. PMID 29763179. Retrieved 2021-06-03.
  20. "Proton Pump Inhibitor drugs (PPIs): Drug Safety Communication - Low Magnesium Levels Can Be Associated With Long-Term Use". www.fda.gov. Archived from the original on 2011-03-04.
  21. Sheen E, Triadafilopoulos G (April 2011). "Adverse effects of long-term proton pump inhibitor therapy". Digestive Diseases and Sciences. 56 (4): 931–950. doi:10.1007/s10620-010-1560-3. PMID 21365243. S2CID 34550326.
  22. al-Ghamdi SM, Cameron EC, Sutton RA (November 1994). "Magnesium deficiency: pathophysiologic and clinical overview". American Journal of Kidney Diseases. 24 (5): 737–752. doi:10.1016/s0272-6386(12)80667-6. PMID 7977315.
  23. Viering D, Schlingmann KP, Hureaux M, Nijenhuis T, Mallett A, Chan MM, et al. (February 2022). "Gitelman-Like Syndrome Caused by Pathogenic Variants in mtDNA". Journal of the American Society of Nephrology. 33 (2): 305–325. doi:10.1681/ASN.2021050596. PMC 8819995. PMID 34607911.
  24. Chareonpong-Kawamoto N, Yasumoto K (February 1995). "Selenium deficiency as a cause of overload of iron and unbalanced distribution of other minerals". Bioscience, Biotechnology, and Biochemistry. 59 (2): 302–306. doi:10.1271/bbb.59.302. PMID 7766029.
  25. Johnson, S. (2001). "The multifaceted and widespread pathology of magnesium deficiency". Medical Hypotheses. Elsevier BV. 56 (2): 163–170. doi:10.1054/mehy.2000.1133. ISSN 0306-9877.
  26. Al-Ghamdi, Saeed M.G.; Cameron, Eugene C.; Sutton, Roger A.L. (1994). "Magnesium Deficiency: Pathophysiologic and Clinical Overview". American Journal of Kidney Diseases. Elsevier BV. 24 (5): 737–752. doi:10.1016/s0272-6386(12)80667-6. ISSN 0272-6386.
  27. Rivlin RS (October 1994). "Magnesium deficiency and alcohol intake: mechanisms, clinical significance and possible relation to cancer development (a review)". Journal of the American College of Nutrition. 13 (5): 416–423. doi:10.1080/07315724.1994.10718430. PMID 7836619.
  28. Gomella LG, Haist SA, eds. (2007). "Chapter 9. Fluids and Electrolytes". Clinician's Pocket Reference: The Scut Monkey (11th ed.). McGraw Hill. ISBN 978-0-07-145428-5.
  29. Desai S, Seidler M (2017). "Metabolic & Endocrine Emergencies". In Stone C, Humphries RL (eds.). Current Diagnosis & Treatment: Emergency Medicine (8th ed.). McGraw Hill. ISBN 978-0-07-184061-3.
  30. Flink EB (December 1986). "Magnesium deficiency in alcoholism". Alcoholism: Clinical and Experimental Research. 10 (6): 590–594. doi:10.1111/j.1530-0277.1986.tb05150.x. PMID 3544909.
  31. Sihler KC, Napolitano LM (January 2010). "Complications of massive transfusion". Chest. 137 (1): 209–220. doi:10.1378/chest.09-0252. PMID 20051407.
  32. Huang CL, Kuo E (October 2007). "Mechanism of hypokalemia in magnesium deficiency". Journal of the American Society of Nephrology. 18 (10): 2649–2652. doi:10.1681/ASN.2007070792. PMID 17804670.
  33. Agus ZS (July 1999). "Hypomagnesemia". Journal of the American Society of Nephrology. 10 (7): 1616–1622. doi:10.1681/ASN.V1071616. PMID 10405219.
  34. Mills R, Leadbeater M, Ravalia A (August 1997). "Intravenous magnesium sulphate in the management of refractory bronchospasm in a ventilated asthmatic". Anaesthesia. 52 (8): 782–785. doi:10.1111/j.1365-2044.1997.176-az0312.x. PMID 9291766.
  35. Pham PC, Pham PM, Pham SV, Miller JM, Pham PT (March 2007). "Hypomagnesemia in patients with type 2 diabetes". Clinical Journal of the American Society of Nephrology. 2 (2): 366–373. doi:10.2215/CJN.02960906. PMID 17699436.
  36. Pham PC, Pham PM, Pham SV, Miller JM, Pham PT (March 2007). "Hypomagnesemia in patients with type 2 diabetes". Clinical Journal of the American Society of Nephrology. 2 (2): 366–373. doi:10.1530/EJE-16-0517. PMID 17699436.
  37. Oost LJ, van der Heijden AA, Vermeulen EA, Bos C, Elders PJ, Slieker RC, et al. (August 2021). "Serum Magnesium Is Inversely Associated With Heart Failure, Atrial Fibrillation, and Microvascular Complications in Type 2 Diabetes". Diabetes Care. 44 (8): 1757–1765. doi:10.2337/dc21-0236. PMID 34385344. S2CID 236991270.
  38. Rodríguez-Morán M, Guerrero-Romero F (April 2003). "Oral magnesium supplementation improves insulin sensitivity and metabolic control in type 2 diabetic subjects: a randomized double-blind controlled trial". Diabetes Care. 26 (4): 1147–1152. doi:10.2337/diacare.26.4.1147. PMID 12663588.
  39. Asbaghi O, Moradi S, Nezamoleslami S, Moosavian SP, Hojjati Kermani MA, Lazaridi AV, Miraghajani M (March 2021). "The Effects of Magnesium Supplementation on Lipid Profile Among Type 2 Diabetes Patients: a Systematic Review and Meta-analysis of Randomized Controlled Trials". Biological Trace Element Research. 199 (3): 861–873. doi:10.1007/s12011-020-02209-5. PMID 32468224. S2CID 218978772.
  40. Verma, H.; Garg, R. (2 February 2017). "Effect of magnesium supplementation on type 2 diabetes associated cardiovascular risk factors: a systematic review and meta-analysis". Journal of Human Nutrition and Dietetics. Wiley. 30 (5): 621–633. doi:10.1111/jhn.12454. ISSN 0952-3871. PMID 28150351. S2CID 19778171.
  41. Fang, Xuexian; Wang, Kai; Han, Dan; He, Xuyan; Wei, Jiayu; Zhao, Lu; Imam, Mustapha Umar; Ping, Zhiguang; Li, Yusheng; Xu, Yuming; Min, Junxia; Wang, Fudi (2016). "Dietary magnesium intake and the risk of cardiovascular disease, type 2 diabetes, and all-cause mortality: a dose–response meta-analysis of prospective cohort studies". BMC Medicine. 14 (1): 210. doi:10.1186/s12916-016-0742-z. ISSN 1741-7015. PMC 5143460. PMID 27927203.
  42. Dekhuijzen, Pauline (21 June 2021). "Magnesium deficiency increases the risk of cardiovascular disease in diabetic patients". Radboud university medical center.
  43. Swaminathan R (May 2003). "Magnesium metabolism and its disorders". The Clinical Biochemist. Reviews. 24 (2): 47–66. PMC 1855626. PMID 18568054.
  44. Davis, Charles Patrick (29 March 2021). "Hypomagnesemia". Medterms medical dictionary a-z list. MedicineNet.
  45. Famularo G, Gasbarrone L, Minisola G (September 2013). "Hypomagnesemia and proton-pump inhibitors". Expert Opinion on Drug Safety. 12 (5): 709–716. doi:10.1517/14740338.2013.809062. PMID 23808631. S2CID 2726503.
  46. Durlach J, Durlach V, Bac P, Bara M, Guiet-Bara A (December 1994). "Magnesium and therapeutics". Magnesium Research. 7 (3–4): 313–328. PMID 7786695.
  47. Firoz M, Graber M (December 2001). "Bioavailability of US commercial magnesium preparations". Magnesium Research. 14 (4): 257–262. PMID 11794633.
  48. Lindberg JS, Zobitz MM, Poindexter JR, Pak CY (February 1990). "Magnesium bioavailability from magnesium citrate and magnesium oxide". Journal of the American College of Nutrition. 9 (1): 48–55. doi:10.1080/07315724.1990.10720349. PMID 2407766.
  49. Walker AF, Marakis G, Christie S, Byng M (September 2003). "Mg citrate found more bioavailable than other Mg preparations in a randomised, double-blind study". Magnesium Research. 16 (3): 183–191. PMID 14596323.
  50. "Abridged List Ordered by Nutrient Content in Household Measure Source: USDA National Nutrient Database for Standard Reference Legacy (2018) Nutrients: Magnesium, Mg(mg)" (PDF). United States Department of Agriculture. Retrieved May 20, 2020.
  51. Hirschfelder AD, Haury VG (1934). "Clinical Manifestations of High and Low Plasma Magnesium; Dangers of Epsom Salt Purgation in Nephritis". Journal of the American Medical Association. 102 (14): 1138. doi:10.1001/jama.1934.02750140024010.
  52. Huner NP, Hopkins W (2008-11-07). "3 & 4". Introduction to Plant Physiology 4th Edition. John Wiley & Sons, Inc. ISBN 978-0-470-24766-2.
  53. Ding Y, Chang C, Luo W (2008). "High Potassium Aggravates the Oxidative Stress Induced by Magnesium Deficiency in Rice Leaves". Pedosphere. 18 (3): 316–327. doi:10.1016/S1002-0160(08)60021-1.
  54. Merhaut DJ (2006). "Magnesium". In Barker AV, Pilbeam DJ (eds.). Handbook of plant nutrition. Boca Raton: CRC Press. p. 154. ISBN 9780824759049.
  55. Hermans C, Vuylsteke F, Coppens F (2010). "Systems Analysis of the responses to long-term magnesium deficiency and restoration in Arabidopsis thaliana". New Phytologist. 187 (1): 132–144. doi:10.1111/j.1469-8137.2010.03257.x. PMID 20412444.
  56. "Problem Solving: Magnesium Deficiency". Gardeners' World Magazine. 6 March 2019.
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.