Magnesium dietary requirements

VoRMANN J, Anke M (2002) Dietary magnesium supply, requirements and recommendations —... 

As is true of many mineral nutrients. Ihc requirement for magnesium is atfected by other dietary constituents, by the age and species of ihc animal. and by lhe criterion ol adequacy applied. An allowance lor magnesium... 

These studies indicate an intimate relation between the magnesium level of the diet and the pyridoxine requirement. It is suggested (A6) that, insofar as growth and urinary excretion of citrates, oxalates, and xanthurenic acid are concerned, high levels of magnesium appear to have a sparing effect on very low dietary levels of pyridoxine. 

Magnesium supplements may reduce hypertension in some persons. The issue of magnesium and the control of blood pressure has been difficult to establish conclusively. One study involving people with moderate hypertension revealed that daily doses of 20 mmol (485 mg) Mg could produce a decline in blood pressure, where at least three continuous months of supplementation were required for the effect (Witteman ( f a ., 1994). The 20-mmol supplement contained about double the usual dietary intake from food. Magnesium sulfate is commonly used as a drug... 

Urinary potassium and magnesium losses are anticipated consequences of AmB therapy. Some of the losses can be compensated for with increased dietary intake, while others will require oral or intravenous replacement. It should be recognized that the serum levels of these ions do not necessarily correlate with the total deficit, as the plasma levels tend to be conserved while cellular stores are becoming depleted. In general, potassium and magnesium supplements should be given to all patients and the amounts increased if the... 

Other electrolytes that require monitoring include magnesium and phosphorus. Both are eliminated by the kidneys and are not removed efficiently by dialysis. Typically their dietary intake is re-... 

Copper is recognized as an essential metalloelement like sodium, potassium, magnesium, calcium, iron, zinc, chromium, vanadium and manganese [1]. Like essential amino acids, essential fatty acids and essential cofactors (vitamins), essential metalloelements are required for normal metabolic processes but cannot be synthesized de novo and daily dietary intake and absorption are required. The adult body contains between 1.4 mg (22 pmol) and... 

Because of their chelating action, tetracycline drugs are inactivated in the patient s bowel by any dietary calcium or magnesium ions, whether from milk or from antacid medication. Through such mishaps, many patients have lost the potential benefit of these antibiotics. Tetracyclines are usually given orally. Tetracycline, itself, is still much prescribed, but there are also lower-dose forms available demeclocycline and methacycline, and a sub-class of these which require less frequent dosing doxycycline and minocycline. 

TABLE 1. Dietary Magnesium Requirements Set by the National Research Council... 

In calculating magnesium allowances, a net daily requirement for maintenance of 3 mg/kg W may be assumed, along with a concentration of 0.125 g/kg in the milk. Availability of dietary magnesium is very low, at about 0.17. 

Apparent magnesium absorption can be determined even with basic quadru-pole-based ICP-MS instruments, which can deliver precisions of 0.2-0.5% RSD for measuring the Mg/ Mg and Mg/ " Mg isotope ratios [208, 209], which is similar to what can be achieved using sector field ICP-MS [210] or collision cell ICP-MS [211]. Such precisions require isotope doses of the order of 20-50 mg to reach enrichments in the percent range in the collected fecal material. This compares with a dietary magnesium intake of about 300 mg per day. 

Vitamins, minerals, and electrolytes— Studies have shown that during moderate to severe stresses, more zinc, copper, magnesium, and calcium are lost in the urine. Furthermore, stress results in altered blood levels of vitamins A and C, and of zinc and iron. Also, part of the response to stress includes water and sodium retention, via veisopressin and aldosterone secretion. As for the water-soluble vitamins—thiamin, riboflavin, niacin, pyridoxine (B-6), pantothenic acid, folic acid, and vitamin C stress increases their requirement. However, no dietary recommendations are made for these nutrients for individuals under stressful situations. Still, it seems wise to supply some supplementation before deficiency symptoms appear. 

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