Farhangi MA, Dehghan P, Tajmiri S, Abbasi MM. The effects of Nigella sativa on thyroid function, serum vascular endothelial growth factor (VEGF)-1, nesfatin-1 and anthropometric features in patients with Hashimoto’s thyroiditis: a randomized controlled trial. BMC Complement Altern Med. 2016;16:471.
Double-blind, placebo-controlled trial
Forty participants, aged 22 to 50 years, with Hashimoto’s thyroiditis; 85% were women. All patients were treated with a stable dose of levothyroxine from 6 weeks prior to participation until the end of the trial. Initially, 47 participants were included in the study; however, 4 in the control group refused to continue the trial and 3 in the Nigella group dropped out because of itching and nausea.
Participants were excluded if they were pregnant or nursing; had other thyroid abnormalities or a history of thyroid surgery; or were taking other nutritional supplements or any specific dietary regimen for 3 months preceding or during the trial.
Study Parameters Assessed
Participants were randomized into 2 groups; the test group received 1 gram encapsulated ground Nigella sativa seeds and the placebo group received similar capsules containing plain starch. Capsules (either Nigella or placebo) were taken twice a day for 8 weeks.
Primary Outcome Measures
Body weight, body mass index (BMI), waist circumference (WC), hip circumference (HC), and waist-to-hip ratio (WHR). Food records were analyzed at the beginning and end of the trial to see if caloric and nutrient intakes would change.
Serum concentrations of thyroid stimulating hormone (TSH), triiodothyronine (T3), thyroxine (T4), antithyroid peroxidase (TPO) antibodies, vascular endothelial growth factor (VEGF), nesfatin-1.
After 8 weeks of treatment, participants in the Nigella group saw a significant reduction in all anthropometric values, while no significant change was seen in the placebo group. Caloric or nutrient intake between the beginning and end of the study did not change significantly in either group.
After 8 weeks of treatment, participants in the Nigella group saw a significant reduction in all anthropometric values.
Participants in the Nigella group also saw an overall reduction in serum TSH (from 6.42±3.86 to 4.13±2.35, P=0.03) and anti-TPO antibodies (from 294.55±210.05 to 147.99±158.33, P=0.019) and an increase in T3 levels. Concentrations of VEGF also decreased overall and were found to be dependent upon changes in WHR. No significant change was seen in nesfatin-1 levels in either group.
As a holistic provider, I frequently see patients in the office looking for treatments to correct the root cause of their autoimmune thyroid condition. As we all know, initiating factor(s) in autoimmune disease can be variable and challenging to pinpoint, and the process of identifying and correcting them will be quite individualized. In addition to thyroid hormone replacement therapy, holistic treatment for autoimmune thyroid issues will often be multifactorial and may address dietary and lifestyle factors and utilize natural therapies to support the thyroid and decrease the inflammatory process. With this in mind, the present study introduces a plant medicine that can help to decrease the inflammatory process while we help remove any other obstacles to healing.
Nigella sativa is an annual flower in the buttercup family with a range of common names, including black cumin, onion seed, and black seed. It has been used as a culinary spice and medicine in Asia and the Middle East for thousands of years. It is mentioned in the Bible, and there is an Islamic belief that it can prevent any malady except death. There have been many studies conducted over the past 2 decades that have shown Nigella sativa can positively affect a large range of diseases, though the current study appears to be the first to look at Nigella's effects on Hashimoto’s thyroiditis.
The primary active constituent isolated from Nigella sativa is thymoquinone. Thymoquinone has been shown to act as a potent antioxidant and antiinflammatory in many contexts and disease patterns, including cancer, diabetes, hyperlipidemia, allergies, and other autoimmune diseases.1-9 In rat studies, thymoquinone showed a protective effect against induced oxidative damage.10,11 Given these actions in the body, it makes sense to consider the therapeutic potential of this plant in autoimmune thyroid disease.
The antioxidant and antiinflammatory actions of Nigella sativa appear to have contributed to the positive outcome of this study via a few proposed mechanisms. One of these is increased lipolysis and decreased lipogenesis secondary to a decrease in VEGF: Multiple studies have found thymoquinone decreases VEGF levels.12,13 Increased VEGF has been found in people with chronic thyroiditis and thyroid cancer, and increased TSH levels increase production of VEGF.14,15 Vascular endothelial growth factor is also associated with metabolic syndrome and obesity, as it expands vasculature to the adipose tissue. The authors of this study postulate that by decreasing VEGF, blood supply to the thyroid and adipose tissue also decreases, which has the effect of decreasing inflammation in the thyroid and shrinking fat stores.
Thymoquinone has also been shown to increase heme oxygenase, which decreases inflammation, particularly in the vascular endothelium.16,17 Increased heme oxygenase is another proposed mechanism in this study for decreased inflammation in the thyroid, leading to decreased anti-TPO antibodies and increased T3 levels.
In general, Nigella has low toxicity and has been reported as well tolerated. However, there are case reports that some people do not digest it well. Also, bear in mind that 3 people dropped out of the treatment group (n=23) because they developed a rash; 13% is a fairly large proportion of test subjects to exhibit signs of sensitivity, and there have been other reports of hypersensitivity reactions to topical Nigella sativa applications.18,19 When using this plant, it would be prudent to tell patients to be on the lookout for any signs of hypersensitivity.
Clinically, Nigella sativa could be a useful adjunct to holistic treatment of Hashimoto’s thyroiditis. It decreases inflammation, helps bring down TSH and anti-TPO, and raises T3. It also helps to reverse some of the weight gain associated with hypothyroidism. It can be used as one powerful piece of a holistic approach to restoring the endocrine and immune systems to a state of optimal health.