On the reliability of the magnesium serum value as an indicator of body magnesium status.

The interrelationships between serum Mg and HCR, and between serum Mg and K were investigated in pigs fed on a low Mg diet. A positive dependence was found between serum Mg and HCR, and between serum Mg and K. It was concluded, that in Mg-deficient pigs, Mg ions originating from soft tissues or erythrocytes can cause an increase of serum Mg level. The serum Mg value, consequently, can not be considered as a reliable parameter indicating the body Mg status. Some difficulties in diagnosing the body Mg status and the effects of the spontaneous increase of serum Mg level on Mg deficiency symptoms were discussed.