The foods in the diet contain a wide range of organic and inorganic compounds. Considering these from an elemental perspective, 5 so-called macroelements, calcium, potassium, sodium, phosphorus and chlorine, are contained in comparatively large quantities in foods compared to all other elements. This chapter attempts to review the importance of these dietary macroelements on oral health, and in particular their role in tooth loss, dental caries, erosive tooth wear and periodontal disease. Calcium and phosphate make up the bulk of the mineralized human tissues. Adequate intake of both is therefore of crucial importance in maintaining the health, function and retention of teeth and bones. Supplementation of the diet with calcium has also been shown to aid in maintaining and improving oral health. Several attempts have been made to lessen the erosive potential of beverages through calcium supplementation. Adequate calcium intake is also crucial for maintaining periodontal health. In many areas, however, the evidence is still emerging or controversial. Phosphate supplementation of the diet was once thought to decrease caries incidence, although studies in children were not successful. Furthermore, little attention has been paid to the other macroelements, highlighting the need for more well-controlled and comprehensive studies.