This document specifies methods for the determination of sodium and magnesium in foodstuffs by flame atomic absorption spectrometry (AAS) after microwave digestion. Collaborative studies have been carried out (Annex A). The method is suitable for the determination of sodium not less than 1 500 mg/kg and magnesium not less than 250 mg/kg. Data for calcium is included for information (Annex B). The method is not applicable to wheat bran.