Criteria for Assessing Magnesium Requirements and Allowances

Reference from the joint report of FAO/WHO expert consultation on Human Vitamins and Minerals verbatim.

44. Shils, M.E. & Rude, R.K. 1996. Deliberations and evaluations of the approaches, endpoints and paradigms for magnesium dietary recommendations. J. Nutr., 126 (9 Suppl): 2398S-2403S.

45. Matos, V., van Melle, G., Boulat, O., Markert, M., Bachman, C. & Guignard, J.P. 1997. Urinary phosphate creatinine, calcium/creatinine and magnesium/creatinine ratios in a healthy pediatric population. J. Pediatr., 131: 252-257.

7. Classen, H.G. 1984. Magnesium and potassium deprivation and supplementation in animals and man: aspects in view of intestinal absorption. Magnesium, 3: 257-264.

8. Al-Ghamdi, S.M., Cameron, E.C. & Sutton, R.A. 1994. Magnesium deficiency: pathophysiologic and clinical overview. Am. J. Kidney Dis., 24: 737-754.

In 1996 Shils and Rude (44) published a constructive review of past procedures used to derive estimates of magnesium requirements. They questioned the arguments of many authors that metabolic balance studies are probably the only practicable, non-invasive techniques for assessing the relationships of magnesium intake to magnesium status. At the same time, they emphasised the great scarcity of data on variations in urinary magnesium output and on magnesium levels in serum, erythrocytes, lymphocytes, bone, and soft tissues. Such data are needed to verify current assumptions that pathologic responses to a decline in magnesium supply are not likely occur to if magnesium balance remains relatively constant.

In view of the recent conclusion that many estimates of dietary requirements for magnesium were “based upon questionable and insufficient data” (44), a closer examination is needed of the value of biochemical criteria for defining the adequacy of magnesium status (13). Attention could be paid to the effects of changes in magnesium intake on urinary magnesium-creatinine ratios (45), the relationships between serum magnesium-calcium andmagnesium-potassium concentrations (7, 8), and other functional indicators of magnesium status.