To obtain the subject composition that reveals its intrinsic taste without bitterness (of magnesium), when it is eaten or drunk, and can add magnesium to food (products) at a high level of concentration by preparing the composition from a specific organic acid and magnesium carbonate.

This composition is produced by mixing an organic acid that is obtained by fermentation, for example, lactic, acetic or malic acid with a solution of magnesium carbonate with stirring. In a preferred embodiment, a fruit juice as lime or lemon may be admixed to this composition. The magnesium carbonate is added to the organic acid in an amount of 0.01-95 wt.% based on the total amount of the acids. Thus, magnesium can be readily formulated at a suitable ratio for the ingestion balance in human body.