Effect of Persian Clover (Trifolium resupinatum L.) Extract on Thyroid Hormones in Subclinical Hypothyroidism: A Double-Blind Clinical Trial

Background and Aim: Subclinical hypothyroidism represents a prevalent endocrine disorder affecting metabolic homeostasis. Trifolium resupinatum L. is a medicinal plant traditionally valued for its therapeutic properties. This study aimed to evaluate the effects of its hydroalcoholic extract on thyroid hormone profiles in patients with subclinical hypothyroidism. Materials and Methods: Hydroalcoholic extract was prepared from dried T. resupinatum samples, and bioactive compounds were identified via GC-MS analysis. In a randomized clinical trial, 51 patients were allocated into two groups. The intervention group (n=25) received extract (500 mg/day) alongside levothyroxine, while the control group (n=26) received levothyroxine plus placebo. Following three months of treatment, serum TSH, total T3, and total T4 levels were measured using ELISA. Statistical analyses were conducted using SPSS software (version 25).