Effects of omega-3 on thyroid function tests in healthy volunteers

Supplements play a pivotal role in medicine especially fish consumption or supplementation with omega 3. Omega-3 and thyroid hormones are important in keeping some essential body functions working normally and alterations of thyroid hormones levels can result in many pathological states. Our study aimed to investigate whether omega-3 supplementation (1000 mg/day for 2 months given orally) would affect thyroid hormones and thyroid-stimulating hormone in healthy volunteers with normal thyroid status. Normal thyroid status of the experimental group was well defined by serum levels of triiodothyronine (T3), thyroxine (T4), and by thyroid-stimulating hormone. Thyroid hormones (T3 and T4) levels were increased insignificantly in treated volunteers compared to the same volunteers before consumption of omega-3 (2.20 ± 0.37 to 2.23 ± 0.39 and 89.87 ± 9.93 to 90.98 ± 11.85 nmol/L, respectively). On the other hand, thyroid-stimulating hormone significantly increased after 2 months of omega-3 consumption (1.46 ± 0.47 to 1.68 ± 0.39 μIu/L). In conclusion, supplementation of omega-3 in the present study did not significantly modify either T3 or T4 and bodyweight in healthy volunteers. These data reinforce recommendations that indicate consumption of omega-3 is considered safe as far as thyroid function is concerned in healthy human volunteers. These findings advocate continued investigation of omega-3 for more than 2 months and higher dose to confirm its safety.