Assessment of essential and toxic trace element imbalances in hypothyroid patients with and without levothyroxine...

Hypothyroidism is a common endocrine disorder associated with widespread disturbances in essential and toxic trace elements. This study aimed to evaluate the serum levels of selected trace and toxic elements in Iraqi hypothyroid patients, both newly diagnosed and under levothyroxine therapy, to identify potential metabolic imbalances on trace element homeostasis. A total of 120 participants were enrolled and divided into three groups: healthy controls, untreated hypothyroid patients, and levothyroxine-treated hypothyroid patients. Serum concentrations of (Cu, Zn, Mg, Ni, Mn, Co, Cr, Al, Fe, Pb, and Cd) were measured using atomic absorption spectrophotometry. Results showed that the untreated patients had significantly lower levels of (Zn: 70.3 ± 9.1 vs 101.1 ± 14.6, Mg: 1.09 ± 0.23 vs 1.57 ± 0.21, Mn: 0.018 ± 0.003 vs 0.186 ± 0.028, Cr: 0.138 ± 0.041 vs 0.167 ± 0.024 and Fe: 73.50 ± 14.70 vs 104.13 ± 16.98, respectively, p < 0.05) compared to controls, while levothyroxine therapy restored Cr and Fe only. In contrast, other elements including Cu, Ni, Al, Pb and Cd remained elevated in both treated and untreated patients (p < 0.05). Correlation analyses revealed antagonistic and synergistic relationships among essential and toxic elements, suggesting complex interactions influencing thyroid function. These findings indicate that trace element dysregulation persists despite hormonal therapy and highlight the importance of monitoring both essential and toxic metals to optimize hypothyroidism management and prevent ongoing metabolic disturbances.