Randomized placebo controlled clinical study of dill (Anethum graveolens L.) in thyroiditis and nodular goiter patients

Abstract

Thyroid nodules are common and affect half of the general population by the age of 60 years. The cause is believed to be due to hypothyroidism, mutational changes, and autoimmunity leading to thyroid carcinoma. Dill, a traditional herbal remedy, has been used to treat thyroid dysfunctions such as hyperthyroidism and hypothyroidism. This study evaluates the effects of dill (Anethum graveolens L.) on patients with thyroiditis and nodular goiter. A study was conducted on patients with benign thyroid nodules. They were divided into two groups; placebo (=35) and dill group (n = 33). Dried and ground dill was put into hydroxypropyl methylcellulose capsules and patients were given three capsules per day for 90 days. Various tests were conducted at the beginning and end of the study, including thyroid stimulating hormone (TSH), free triiodothyronine (FT3), free thyroxine (FT4), anti-thyroid peroxidase (anti-TPO), anti-thyroglobulin (anti-Tg), and C-reactive protein (CRP) analysis, and thyroid nodule dimensions were measured by ultrasound. Statistical analysis was performed. After 90 days of treatment with dill extract, patients showed significant reductions in TSH, FT4, anti-TPO, and CRP levels, as well as a decrease in thyroid nodule sizes as demonstrated by ultrasonography. The dill-treated group had significantly decreased TSH (P = .020), FT4 (P = .001), anti-TPO (P = .004), CRP (P = .003) levels, and nodule sizes (P = .001) at the beginning and end of the study. Compared to the control group, the dill group had significantly decreased TSH (P = .009), fT4 (P < .001), anti-TPO (P = .001), CRP (P < .001) levels and nodule sizes (P < .001), which reached normal values. A. graveolens suppressed inflammation of the thyroid gland, reduced nodule size, and normalized TSH levels. Dill supplementation should be recommended for the treatment of thyroid nodules in selected patients.