Metabolic, liver, and kidney biomarkers

Participants with taste problems had lower serum albumin (4.15 g/dL vs. 4.27 g/dL, p=0.013) but higher alkaline phosphatase (75.5 IU/L vs. 68.0 IU/L; p=0.009), creatinine (0.99 mg/dL vs. 0.91 mg/dL; p=0.030), and lactate dehydrogenase (LDH) (135.9 IU/L vs. 129.5 IU/L; p=0.042). Conversely, serum chloride levels were lower in those with taste problems (102.9 mmol/L vs. 103.8 mmol/L; p=0.008). No differences were observed for other liver or kidney biochemical markers (Supplementary Table 1).

Environmental heavy metals and trace minerals

Among the analyzed trace minerals and heavy metals, serum copper was the only one that was significantly different between the two groups (p=0.046), with higher concentrations in individuals reporting taste problems (124.3 µg/dL, SE=3.6) than in those without (116.6 µg/dL, SE=1.4). Serum iron levels were lower in those with taste problems (79.9 µg/dL vs. 87.5 µg/dL), but this was not significant (p=0.065). Other minerals and heavy metal levels did not differ between the two groups (Supplementary Table 1).

Circulating serum lipid levels and hematologic indices

No statistically significant differences were detected across circulating serum lipid profiles (total and direct cholesterol, LDL cholesterol and triglycerides) or hematologic indices (total and differential white blood cell count, red blood cell count, hemoglobin, red blood cell indices and platelet count) (Supplementary Table 1).