Investigating the Impact of Vitamin D and Selenium on Subclinical Hashimoto’s Thyroiditis

Investigation of the therapeutic effect of vitamin D with selenium on antioxidant indices and hormonal changes and anti-thyroperoxidase antibody in patients with subclinical Hashimoto's thyroiditis and vitamin-D deficiency

Status

Recruiting

Phases

Phase 3

Study type

Interventional

Source

IRCT

Registry ID

IRCT20250409065265N1

Enrollment

Registered

2025-09-17

Start date

2025-09-21

Completion date

Unknown

Last updated

2025-10-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Subclinical Hashimoto Thyroiditis. Autoimmune thyroiditis. Hashimoto thyroiditis

Interventions

Intervention 1: Intervention group: Vitamin D supplement with selenium. Name of the substance used: Vitamin D3 supplement (cholecalciferol) and selenium supplement in the form of sodium selenite. Chem

Eligibility

Sex/Gender

All

Age

18 Years to 65 Years

Inclusion criteria

Inclusion criteria: Age range of participants: 18 to 65 years. Normal serum T4 levels, with elevated TSH levels (<10 mIU/L) Positive anti-thyroid peroxidase antibodies (Anti-TPO). Candidates eligible for initiation of levothyroxine treatment. Serum 25-hydroxy vitamin D levels between 10–20 ng/mL. No history of selenium supplementation within the past 3 months.

Exclusion criteria

Exclusion criteria: Patients with conditions that may lead to systemic inflammation and potentially alter autoimmune responses will be excluded. These include:Individuals with a BMI>35 Patients with any chronic or inflammatory diseases, such as severe renal or hepatic disorders, severe rheumatoid diseases, or severe chronic obstructive pulmonary disease (COPD) Patients who are currently taking anti-inflammatory medications, including glucocorticoids or any type of corticosteroids

Design outcomes

Primary

Measure	Time frame
Serum anti-thyroperoxidase antibody (Anti-TPO). Timepoint: Measured at baseline, 3 months, 6 months. Method of measurement: Autoanalyzer device.;Serum thyroid stimulating hormone (TSH). Timepoint: Measured at baseline, 3 months, 6 months. Method of measurement: Autoanalyzer device.;Serum malondialdehyde (MDA). Timepoint: Measured at baseline, 3 months, 6 months. Method of measurement: Using enzyme linked immunosorbent assay kit.;Serum glutathione peroxidase (GPx). Timepoint: Measured at baseline, 3 months, 6 months. Method of measurement: Using enzyme linked immunosorbent assay kit.;Serum Vitamin D level. Timepoint: Measured at baseline, 3 months, 6 months. Method of measurement: High performance liquid chromatography(HPLC) device.;Serum Selenium level. Timepoint: Measured at baseline, 3 months, 6 months. Method of measurement: Using atomic absorption spectrophotometer.	—

Measure

Time frame

Serum anti-thyroperoxidase antibody (Anti-TPO). Timepoint: Measured at baseline, 3 months, 6 months. Method of measurement: Autoanalyzer device.;Serum thyroid stimulating hormone (TSH). Timepoint: Measured at baseline, 3 months, 6 months. Method of measurement: Autoanalyzer device.;Serum malondialdehyde (MDA). Timepoint: Measured at baseline, 3 months, 6 months. Method of measurement: Using enzyme linked immunosorbent assay kit.;Serum glutathione peroxidase (GPx). Timepoint: Measured at baseline, 3 months, 6 months. Method of measurement: Using enzyme linked immunosorbent assay kit.;Serum Vitamin D level. Timepoint: Measured at baseline, 3 months, 6 months. Method of measurement: High performance liquid chromatography(HPLC) device.;Serum Selenium level. Timepoint: Measured at baseline, 3 months, 6 months. Method of measurement: Using atomic absorption spectrophotometer.

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Countries

Iran (Islamic Republic of)

Contacts

Public ContactZahra Azadkhani

Esfahan University of Medical Sciences

za.azadkhani1610@gmail.com+98 31 3792 7043

Outcome results

None listed

Source: IRCT (via WHO ICTRP) · Data processed: Feb 4, 2026