Objective: 

Fenugreek seeds (Trigonella foenum-graecum L.) are assumed to have restorative and nutritive properties. The present study was undertaken to investigate the effect of aqueous extract of fenugreek seeds on thyroid gland function.

Methods: 

Male Wistar rats (n= 40) were divided into four groups of ten rats each as follows; Group I: control, Group II: 0.4, Group III: 0.8, and Group IV: 1.6 g/kg body weight of fenugreek seeds extract. Extract was administered daily and orally for 15 days.

Results: 

There was a gain in body weight and thyroid gland weight in the treated groups as compared with the control. Furthermore results of treated groups showed a significant decrease (P< 0.05) in serum total and free triiodothyronine (T3) and tetraiodothyronine (thyroxin, T4) levels. However serum thyroid stimulating hormone (TSH) levels were increased. On the other hand, there was significant decrease of total T3 and T4 in thyroid gland tissue. In the liver tissue, the level of T3 decreased while T4 increased which may indicate an inhibitory action on the conversion of T4 to T3 as compared with the control group.

Conclusions: 

Treatment with fenugreek seeds extract caused significant decreases in serum total and free thyroid hormones T3 and T4, which were also decreased in the thyroid tissue, except for T4 that was increased in the liver tissue. The effect of extract was dose dependent.