The studies pertain laboratory evaluation of Mg content as well as interrelations between Mg and Ca in reconstructed daily food rations of the drawn at random, representative selected groups of population from the Wielkopolska region. The studies have been conducted in four consecutive seasons of the year, separately for each sex. The studied food rations covered neither safe nor recommended levels of Mg consumption except of preschool children. Food rations of secondary school youth and of female pensioners satisfied safe levels of Mg feeding norms in less than 60%. The most favourable Ca:Mg rations, based on analytically determined values, were found in daily food rations of secondary school youth and academic school students of either sex as well as of mental workers and female pensioners. Improper relations between Mg and Ca content in daily food rations in all studied population groups, as related to energetic value of the food rations, should be regarded to represent an unfavourable phenomenon.