Parallel investigation of oxidative stress and nutritional profile in women with Hashimoto's thyroiditis

Genetic predisposition, inflammation, and oxidative stress are known contributors to the development of Hashimoto's thyroiditis (HT). While genetic factors are non-modifiable, lifestyle, nutritional factors and oxidative stress may represent areas for intervention. This study aimed to assess biochemical markers of oxidative stress and evaluate dietary intake in women with newly diagnosed HT, identified through population-based screening. A cross-sectional analysis was conducted on 600 women aged 18-45 years, where 92 were diagnosed with euthyroid HT. Nutrients, based on a seven-day food diary, and biochemical evaluation, including thyroid autoantibodies (anti-thyroid peroxidase (ATPO) and anti-thyroglobulin (ATG)), metabolic parameters, and oxidative stress markers (total oxidative capacity (TOC), total antioxidant capacity (TAC), TOC/TAC ratio), were performed. Results revealed elevated TOC and TOC/TAC ratios in the HT group, suggesting oxidative stress despite preserved TAC. Dietary analysis showed significantly lower intake of cholesterol (p = 0.017) and retinol (p = 0.014) in the HT group. Additionally, negative correlations were observed between ATPO levels and dietary intake of vitamin E (r = -0.33; p < 0.01), vitamin C (r = -0.22; p = 0.05), and retinol (r = -0.23; p = 0.04). While ATG levels correlated negatively with HDL (r = -0.30; p = 0.01) and retinol (r = -0.23; p = 0.04). Additionally, TOC levels showed positive correlations with fasting insulin (r = 0.30; p = 0.01), triglycerides (r = 0.25; p = 0.04), and free triiodothyronine (FT3) (r = 0.28; p = 0.01) concentrations, suggesting potential links between oxidative stress, metabolic activity, and thyroid function. In conclusion, maintaining an adequate intake of antioxidant nutrients with limiting potentially pro-oxidative dietary factors, may represent a reasonable adjunctive approach in the dietary management of HT. Further research is needed to clarify the role of diet in modulating oxidative stress and immune activity in HT and to explore its potential as a supportive strategy in disease management.