Background. There is a need for assessing personalized nutritional status of the bio elements magnesium (Mg) and calcium (Ca). Objective. We studied the Mg and Ca nutritional status by analyzing their concentrations frequency distribution in the long-term biological indicator tissue of hair. Design. Hair Mg and Ca were analyzed in 1073 apparently healthy white adult Caucasians of both sexes [734 women (♀) and 339 men (♂)] with the ICP MS. The concentrate frequency distribution data were log transformed and the nutritional status assessed with the Median Derivatives Bioassay. Results. The hair median values (µg∙g-1) were Women (♀) Mg 254 and Men (♂) Mg 137.2 whereas W (♀) Ca median was 721.4 and M (♂) Ca 492.0, respectively. Adequate nutritional status range limits arranged themselves along the linear part of the sigmoid saturation curve. These linear adequate window range limits were for women magnesium W (♀) Mg 29.7–270.6 and for men M (♂) Mg 20.5–90.2. The adequate range limits for calcium were W (♀) Ca 487.7–4456.8 and M (♂) Ca 26.1–816.4. The bone seeking bio elements Ca, Mg, and Sr showed the same increasing affinity for women hair deposition, whereas the major cellular electrolytes of sodium and potassium were almost imperceptibly higher in men than women. Conclusions. Women hair incorporates Mg and Ca at about 2.5 times higher rate than men hair. The hair Median Derivatives Bioassay is a convenient painless way to assess and monitor the personalized dietary nutritional status of Mg and Ca in women and men.