Trace Elements in Saliva as Markers of Type 2 Diabetes Mellitus

To analyze Mg, Ca, and Zn levels in saliva, comparing patients with type 2 diabetes mellitus and a control group of healthy subjects. This transversal, observational, clinical study included a total sample of 147 patients, 74 with type 2 diabetes mellitus and a control group of 73 healthy subjects. Socio-demographic, anthropometric, diabetological, and metabolic variables were registered. Trace elements in non-stimulated basal saliva were measured using inductively coupled plasma mass spectrometry (ICP-MS): Mg, Ca, and Zn. Concentrations of zinc, calcium, and magnesium were significantly higher in the diabetic group than the control group (p < 0.001). A relation was observed between waist circumference and high cardiovascular risk in men (based on two categories: waist circumference < 102 cm; waist circumference ≥ 102 cm), and magnesium levels in saliva (p = 0.003). Magnesium, zinc, and calcium levels in saliva could be useful markers for differentiating patients with type 2 diabetes mellitus from non-diabetics. The salivary magnesium could be used as a marker of high cardiovascular risk when associated with abdominal obesity represented by a waist circumference ≥ 102 cm in men. The present results do suggest that salivary zinc levels could act as a good marker of type 2 diabetes mellitus, in light of zinc's well-known role as a co-marker of insulin and its relationship to carbohydrate metabolism.