Calcium-Magnesium Balance

Calcium Cannot Be Optimally Utilized Without a Proper Balance of Magnesium

Magnesium and calcium are two sides of a physiological coin: they are antagonistic to one another yet operate as a team.  For example:

  • Calcium exists mainly outside the cells, whereas almost all magnesium is found inside the cells.

  • Calcium excites nerves; magnesium calms them down. 

  • Calcium with potassium makes muscles contract, but magnesium is necessary for muscles to relax. 

  • Calcium is necessary to the clotting reaction – essential for wound healing – but magnesium keeps the blood flowing freely and prevents abnormal thickening when clotting reactions would be dangerous. 

  • Calcium is mostly found in the bones and gives them much of their hardness, whereas magnesium is found mainly in soft structures. Bone matrix, the soft structure within bone, contains protein and magnesium and gives the bones some flexibility and resistance to brittleness.

Without Adequate Magnesium, Too Much Calcium May Cause Damage to the Cells and the Body

Scientific study shows more and more that the underlying cellular change enabling the “fight or flight” stress response in the body is a low magnesium-to-calcium ratio caused by a large and sudden influx of calcium into the cells. The stress response subsides when the cells’ magnesium returns to its dominant presence inside the cells, moving extra calcium back to its “normal” position thus restoring the cells’ normal ratio.

A low magnesium condition can be exacerbated by a high intake of calcium – promoted heavily today by many health professionals. Calcium cannot be optimally utilized without a proper balance of magnesium, and a high calcium intake without adequate magnesium nutrition and/or status can further drain any reserves of magnesium. Calcium is necessary at the cellular level for muscles to contract, for nerves to fire, for hormones to be secreted and for the inflammation response to initiate. But calcium needs to be balanced with magnesium. If you take in too much calcium and too little magnesium over an extended time period and a cellular/physiological imbalance between calcium and magnesium occurs, what can tend to happen is the excited firing state of biochemistry of the cell will tend to remain that way. In a stress situation such as exercising more vigorously than usual or when someone is suddenly and unexpectedly frightened, muscle cells, nerve cells, hormone secreting cells or the inflammation response can go into an overreaction mode – the fight or flight mode. Without magnesium they don’t come back down to a resting state; they stay excited in that firing mode.

If calcium levels inside a cell get especially high because of low magnesium, the cell physically changes. High calcium tends to make things stiff and hard. But if soft tissue begins to get hard, it is a problem – the problem of calcification. In artery and heart cells, the stiffness caused by calcification hampers proper function and can lead to heart disease.

Calcium is an important essential nutrient, but it must be balanced by adequate magnesium or it may cause damage to the cells and the body as a whole.

Can there be too much magnesium and too little calcium? Of course. In this age of highly processed foods and the liberal use of essential nutrient supplementation, imbalances are always possible. A practicing physician or health professional must always be open to this possibility. This is especially dfficult as symptoms of “too much” of an essential nutrient often mimic symptoms brought on by “too little” of the same nutrient. But at this time, with a largely low magnesium diet and a general recommendation, especially to women, that they supplement their calcium, the imbalance of too much calcium to too little magnesium is one to regularly consider.

To read more on the research on aspects of the calcium to magnesium ratio, see:

Costello R, Nielsen FH, Rosanoff A, et al. Monitoring the Serum Ca/Mg Ratio in Response to Magnesium Supplementation. International Magnesium Symposium XV. Bethesda, MD: SDRM, 2019.

Rosanoff A. Rising Ca:Mg intake ratio from food in USA Adults: a concern? Magnes Res 2010;23(4):S181-93. doi: 10.1684/mrh.2010.0221

Resnick, L. (1999). “The cellular ionic basis of hypertension and allied clinical conditions.” Prog Cardiovasc Dis 42(1): 1-22.

Resnick, L. M. (1992). “Cellular calcium and magnesium metabolism in the pathophysiology and treatment of hypertension and related metabolic disorders.” Am J Med 93(2A): 11S-20S.

Resnick, L. M. (1992). “Cellular ions in hypertension, insulin resistance, obesity, and diabetes: a unifying theme.” J Am Soc Nephrol 3(4 Suppl): S78-85.

Resnick, L. M. (1993). “Ionic basis of hypertension, insulin resistance, vascular disease, and related disorders. The mechanism of “syndrome X”.” Am J Hypertens 6(4): 123S-134S.

Dai, Q., M. J. Shrubsole, et al. (2007). “The relation of magnesium and calcium intakes and a genetic polymorphism in the magnesium transporter to colorectal neoplasia risk.” Am J Clin Nutr 86(3): 743-51.

van der Pols, J. C., C. Bain, et al. (2007). “Childhood dairy intake and adult cancer risk: 65-y follow-up of the Boyd Orr cohort.” Am J Clin Nutr 86(6): 1722-9.

Bardicef, M., O. Bardicef, et al. (1995). “Extracellular and intracellular magnesium depletion in pregnancy and gestational diabetes.” Am J Obstet Gynecol 172(3): 1009-13.

Mauskop, A., B. T. Altura, et al. (1993). “Deficiency in serum ionized magnesium but not total magnesium in patients with migraines. Possible role of ICa2+/IMg2+ ratio.” Headache 33(3): 135-8.

Haenni, A., L. Berglund, et al. (1997). “The alterations in insulin sensitivity during angiotensin converting enzyme inhibitor treatment are related to changes in the calcium/magnesium balance.” Am J Hypertens 10(2): 145-51.

Matsuzaki, H., S. I. Katsumata, et al. (2005). “Effects of high calcium intake on bone metabolism in magnesium-deficient rats.” Magnes Res 18(2): 97-102.

Seelig, M. S., B. M. Altura, et al. (2004). “Benefits and Risks of Sex Hormone Replacement in Postmenopausal Women.” J Am Coll Nutr 23(5): 482S-496.

Cronin, R. E., E. R. Ferguson, et al. (1982). “Skeletal muscle injury after magnesium depletion in the dog.” Am J Physiol 243(2): F113-20.

Sinert, R., M. Spektor, et al. (2005). “Ionized magnesium levels and the ratio of ionized calcium to magnesium in asthma patients before and after treatment with magnesium.” Scand J Clin Lab Invest 65(8): 659-70.

Gopal, A. and M. J. Budoff (2006). “Coronary calcium scanning.” Am Heart Hosp J 4(1): 43-50.

Maitani, T. and K. T. Suzuki (1981). “Metal content ratio as a sensitive indicator of pulmonary edema.” Toxicol Lett 9(3): 295-300.


Magnesium may be key to calcium’s cancer benefits: study – – Europe

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