Abstract:
Introduction: Hypothyroidism is a common endocrine disorder, ranging from 0.1% to 12.5%; women
are more likely to develop the condition. The causes can be multiple, but most often 20-30% of cases
are of autoimmune origin. Vitamin D supplementation has shown potential benefits in improving
thyroid function in individuals with hypothyroidism and concurrent vitamin D deficiency, particularly
in cases involving autoimmune thyroid diseases. The evidence suggests that vitamin D may play a role
in modulating immune responses and enhancing thyroid hormone levels, although the effects can vary
based on the duration and dosage of supplementation.
Material and Methods. Have been selected and analyzed 24 articles from PubMed, NCBI, Google
Scholar, as well as medical books, scientific journals published in the 2012-2024 period.
Results. Long-term vitamin D supplementation, greater than three months, has been associated with
significant improvements in thyroid-stimulating hormone (TSH), triiodothyronine (T3), and thyroxine
(T4) levels in patients with autoimmune thyroid diseases. In patients with Hashimoto’s thyroiditis,
vitamin D supplementation significantly reduced anti-thyroid peroxidase antibody and thyroglobulin
antibody levels, while also decreasing TSH and increasing free T3 and free T4 levels. Vitamin D
correction in subclinical hypothyroid patients led to a significant decrease in TPO-Ab and anti-TG
antibody levels, suggesting an improvement in thyroid autoimmunity. The meta-analysis of
Hashimoto’s thyroiditis patients indicated that active forms of vitamin D, such as calcitriol, were more
effective in reducing TPO-Ab levels compared to vitamin D2 or D3, especially with treatment
durations exceeding 12 weeks.
Coclusions. Supplementation with vitamin D, alongside other micronutrients, showed improvements
in insulin resistance and physical quality of life in hypothyroid patients, although no significant
changes were observed in TSH or FT4 levels in the short term.
