Mediterranean diet, selenium and Graves' ophthalmopathy: a prospective, randomized, single-center study

Area of Science:

• Endocrinology
• Nutrition Science
• Ophthalmology

Background:

• Graves' ophthalmopathy (GO) is an autoimmune condition affecting Graves' disease (GD) patients, linked to oxidative stress, inflammation, and insulin resistance.
• Selenium, a component of selenoproteins, can suppress reactive oxygen species (ROS) production, potentially mitigating GO's inflammatory processes.

Purpose of the Study:

• To evaluate the effects of a selenium-enriched Mediterranean diet (MD) on thyroid function, nutritional status, autoimmunity, and clinical outcomes in GD patients with active mild GO.
• To assess the MD's impact on oxidative stress markers and inflammatory pathways in GO.

Main Methods:

• A randomized controlled trial involving 40 GD patients with mild active GO assigned to either a selenium-enriched MD or a free diet (FD) for 24 weeks.
• Clinical evaluations included thyroid function tests, autoimmunity markers, ophthalmological assessments (Clinical Activity Score, Hertel measurements, eye motility, soft tissue involvement, eyelid aperture), and body mass index (BMI) tracking.

Main Results:

• The MD group showed significant improvements in the Clinical Activity Score (CAS) and soft tissue involvement compared to the FD group.
• Reduced eyelid aperture and lower relative BMI change were observed in the MD group.
• No significant differences were found in thyroid function, TRABs, Hertel measurements, or eye motility between groups. No GO exacerbations occurred.

Conclusions:

• A selenium-enriched Mediterranean diet is a beneficial dietary strategy for managing mild Graves' ophthalmopathy in GD patients.
• The MD can help reduce weight regain, inflammation, and insulin resistance, contributing to better management of the autoimmune-inflammatory processes in GO.