Purpose: Taste dysfunction affects quality of life, yet its biological development remains poorly understood. Methods: We investigated clinical and biochemical differences between 50 patients with idiopathic dysgeusia and 102 healthy controls (110 women, 42 men; mean age 46.4 ± 1.4 years). Each participants underwent a clinical anamnesis, a taste test, and a blood analysis. Results: Patients were older (61 vs. 39 years; p < 0.001) and more often female (86% vs. 66%; p = 0.009). Patients had lower Taste Strips scores, and higher scores on depression (Beck Depression Index) and mood-related questionnaires (Zerssen Mood Scale; both p < 0.001). Blood analyses revealed that patients had higher levels of complement C4 (p = 0.011) and calcium (p = 0.019 ANCOVA, age-controlled). A logistic regression model including age, gender, C4, Ca, K, and transferrin predicted taste dysfunction with high accuracy (Nagelkerke R²=0.74; 91.4% correctly classified). Increased age, higher C4 and female sex were associated with higher odds of taste dysfunction, while higher potassium, transferrin levels, and salivary calcium were protective (p ≤ 0.030). Conclusion: These findings suggest that taste dysfunction is accompanied by systemic inflammatory conditions and lower levels of electrolytes in serum may contribute to development of taste diseases. Overall, the results suggest that idiopathic dysgeusia appears to be related to metabolic imbalance.