Effects of Dietary Habits on Markers of Oxidative Stress in Subjects with Hashimoto's Thyroiditis: Comparison Between the Mediterranean Diet and a Gluten-Free Diet.

BACKGROUND

The Mediterranean diet (MedD) exerts anti-inflammatory and anti-oxidant effects that are beneficial in autoimmune thyroid diseases (ATD). Recently, a gluten-free diet (GFD) has been proposed for non-celiac patients with Hashimoto's thyroiditis (HT), but its usefulness is under debate. The present pilot study evaluates the effects of these two dietary regimes, with a focus on redox homeostasis, in HT.

PATIENTS AND

METHODS

45 euthyroid HT patients (30 F; median age 42 years) were randomly assigned to different dietary regimes: MedD (n = 15), GFD (n = 15) and free diet (FD, n = 15). Thyroid function tests, autoantibodies, and oxidative stress markers (Advanced glycation end products, AGEs; glutathione peroxidase (GPx), thioredoxin reductase (TRxR), and total plasma antioxidant activity (TEAA) were measured at baseline and after 12 weeks.

RESULTS

In the MedD group, significantly lower values of AGEs and higher values of GPX, TRX and TEAA with anti-oxidant action were detected (p < 0.05) at 12 weeks compared to baseline, and compared to the GFD and FD groups, in which the oxidative stress parameters did not change significantly (p > 0.05). No significant differences in serum levels of TSH, FT4, Ab-Tg, Ab-TPO compared to baseline were found in any group.

CONCLUSIONS

This pilot study confirms the protective effect of the MedD against oxidative stress, while a GFD does not significantly influence markers of oxidative stress and/or thyroid autoimmunity/function parameters.