Blood Glucose Lowering Effects of Nigella Sativa L. Seeds Oil in Healthy Volunteers: a Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Background: Several formulations of the Nigella sativa L. seeds (Black seed) have been used in traditional medicine for treatment and prevention of a wide range of diseases including diabetes. But blood glucose lowering effects of its oil in a clinical study is of an interest. Objective: The present study was undertaken to explore the possible blood glucose lowering effects of the Black seed oil on healthy subjects. Methods: A randomized clinical trial was conducted in 70 healthy subjects referring to Bagiatallah hospital. The subjects were randomly selected and enrolled in to two groups of 35 each. One group received 2.5 ml Black seed oil and the other group received similarly 2.5 ml mineral oil two times a day. The fasting blood glucose, HbA1c, liver and renal function test was determined at the baseline and after two months. Results: Results showed that significant decrease in fasting blood glucose and HbA1c levels in Black seed oil treated patients as compared to control group at the end of the study. No notable liver, kidney and gastrointestinal side effects were observed in these two groups. Conclusion: Administration of 5 ml Black seed oil daily to healthy subjects for two months had beneficial effects on improving glycemic profile without any adverse effects.