Magnesium-to-Calcium Ratio and Mortality from COVID-19
Obesity, type 2 diabetes, arterial hypertension, decrease in immune response, cytokine storm, endothelial dysfunction, and arrhythmias, which are frequent in COVID-19 patients, are associated with hypomagnesemia. … our results show that a magnesium-to-calcium ratio ≤0.20 is strongly associated with mortality in patients with severe COVID-19.

More on Mg/Ca ratio:

Maintaining an appropriate balance between magnesium and calcium is crucial for various bodily functions, including bone health, cardiovascular function, and neuromuscular activities. The optimal magnesium-to-calcium (Mg:Ca) ratio has been a subject of research, with studies suggesting that an imbalance may be associated with health issues.

Optimal Magnesium-to-Calcium Ratio
Dietary Intake Ratio: Research indicates that a calcium-to-magnesium (Ca:Mg) intake ratio between 1.7:1 and 2.6:1 is associated with favorable health outcomes. This means consuming 1.7 to 2.6 times more calcium than magnesium in your diet. For example, if your daily magnesium intake is 400 mg, your calcium intake should range between 680 mg and 1,040 mg.
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Serum Ratio: In terms of blood levels, a serum Ca:Mg ratio between 2.36:1 and 3.66:1 is considered within the normal range. This reflects the balance of these minerals circulating in the bloodstream.
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Health Implications of Imbalance
High Ca:Mg Ratio: An elevated calcium-to-magnesium ratio has been linked to increased inflammation markers, which may contribute to chronic conditions such as cardiovascular disease, metabolic syndrome and higher mortality rates in patients with severe COVID-19.
PubMed Central
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