Vitamin A and E status across the spectrum of Hashimoto’s thyroiditis in women: associations with autoimmunity and thyroid function

IntroductionThe status of fat-soluble vitamins (A, D, E) across the spectrum ofHashimoto’s thyroiditis (HT), particularly regarding sex-specific patterns, remainsincompletely characterized.MethodsThis cross-sectional study aimed to evaluate the associations of these vitamins with thyroid autoimmunity and function. We analyzed 196 adults, focusing on the 136 women stratified into healthy controls (HC), euthyroid HT (E-HT), and dysfunctional HT (HT-dys).ResultsIn women, serum vitamin A levels were significantly lower in both the E-HT and HT-dys groups compared to the HC group. Lipid-normalized vitamin E (α-tocopherol/[total cholesterol+triglycerides], αT/[TCH+TG]) was significantly reduced in the HT-dys group compared to both the HC and E-HT groups. Vitamin A levels showed an inverse association with thyroglobulin antibody (TgAb), while αT/(TCH+TG) was inversely associated with both thyroid peroxidase antibody (TPOAb) and TgAb. Among women with HT, αT/(TCH+TG) was inversely correlated with thyroid-stimulating hormone (TSH) and positively correlated with free thyroxine (FT4). An exploratory analysis indicated that this association between vitamin E and thyroid function was largely independent of TPOAb levels.ConclusionThis exploratory study identifies distinct associations of vitamins A and E with disease activity in women with HT, highlighting the need for longitudinal and interventional studies to further explore these relationships.