Black seed oil has been used for its therapeutic benefits for thousands of years. Since the pandemic began, researchers have been evaluating the effect it may have on COVID-19.
The seeds come from the Nigella sativa (N. sativa) plant that grows in Southern Europe, Southwest Asia, and the Middle East. Traditional medicine healers have used the seeds in different forms.
Black seed is coal-black with a dull surface and shaped like tiny Brazil nuts. The bioactive components include thymoquinone, alpha-hederin, alkaloids, and omega-6 fatty acids.
Black seed oil has also been used for dermatological applications. For example, a review of the literature in the Journal of Dermatology & Dermatologic Surgery found black seed oil could promote wound healing in farm animals and reduce the effects of vitiligo in lizards.
In one clinical study in humans, lotion infused with 10 percent of N. sativa oil reduced acne vulgaris after two months, with 67 percent of the patients fully satisfied and 28 percent partially satisfied with the results.
In the current research, scientists believe the oil may have promising benefits in the treatment and prevention of COVID-19. However, while short-term use for treatment may be advantageous, it’s wise to avoid long-term use for prevention.
Black Seed Oil May Be Promising Option for COVID-19
Historically, black seed oil has been used to help balance the inflammatory response in the body as well as reduce oxidative stress, inflammation, and ischemia (a restriction in blood supply to some parts of the body). Using recent computational findings, one research group found the active ingredients in N. sativa were “strongly suggestive” of a capability to combat COVID-19.
The review paper, which looked at several previous studies of N. sativa, suggests that the active ingredients, especially thymoquinone, alpha-hederin, and nigellidine may be an alternative herbal treatment in the fight against COVID-19. The paper reviews several biochemical pathways that the active ingredients in black seed oil may use to protect health.
For example, the researchers reviewed past studies that demonstrated the actions the active ingredients in black seed oil have on the immune system that may help reduce the severity of COVID-19. The active compounds have a significant antihistamine effect in animal studies and thymoquinone downregulates interferon regulatory factor 3 activation, which plays a critical role in innate immune responses.
Autophagy is a mechanism that clears out damaged cells in the body. Data has shown that COVID-19 suppresses autophagy and pharmacological agents used to induce the process may therefore have an antiviral effect. One study published in 2018 indicated thymoquinone promotes autophagy in the heart muscle. The researchers suggested that further study should be undertaken to determine if thymoquinone has a similar effect with COVID-19.
Severe COVID-19 is characterized by cytokine storms that may require intensive care. Animal studies have demonstrated that the bioactive compound alpha-hederin has anti-inflammatory activity and can decrease histamine levels which can in turn lower cytokine levels.
The researchers reported one study had found thymoquinone helped inhibit two enzymes that produce inflammatory leukotriene and prostaglandins. Researchers suggest that these actions may potentially make the active compounds in N. sativa useful in the treatment and prevention of SARS-CoV-2 viral infections.
Finally, in their review of comorbid conditions associated with COVID-19, the researchers found that N. sativa may have a positive effect against diabetes, high blood pressure, heart disease, autoimmune and autoinflammatory diseases, and bacterial infections associated with COVID-19.
After a review of the evidence, the researchers suggest that further experiments with the active compounds found in black seed oil are required to determine if they have preventive potential or may provide a new treatment modality.
Zinc Combinations Help Treat COVID-19
Research into medications that may influence COVID-19 has included antivirals. One such antiviral being studied is favipiravir. Data show the drug was approved and has been used for flu infections in Japan. In late 2020, a study published in PNAS revealed that when given in high doses to hamsters, favipiravir had promising antiviral activity against SARS-CoV-2.
However, a computer-model molecular docking study published in Biological and Medicinal Chemistry revealed that the bioactive compounds nigellidine and alpha-hederin found in black seed oil were able to inhibit SARS-CoV-2 with greater potential than favipiravir, chloroquine, and hydroxychloroquine.
Evidence from a second paper that reviewed the biological effects of the active compounds in black seed oil suggested that thymoquinone may block ACE2 receptors, which is where the SARS-CoV-2 binds to the cell and releases the viral RNA into the cytoplasm.
Contrary to what the PNAS hamster study found, these researchers hypothesized that chloroquine, and potentially the derivative hydroxychloroquine, may also interfere with the virus’s ability to bind with the ACE2 receptors.
This is one pathway the researchers suggest that black seed oil may use in the treatment of COVID-19. Another pathway is as a zinc ionophore. The body uses zinc in several pathways to support the immune system, including:
- Proliferation and activation of natural killer cells, macrophages, neutrophils, and T and B cells
- Mediating protection against reactive oxygen species produced during an inflammatory response
- Stopping recombinant RNA dependent RNA polymerase activity needed to replicate SARS-CoV-2
- Inhibiting replicase processing
Therefore, moving zinc into the cytoplasm is crucial to help prevent the replication of the SARS-CoV-2 virus and thus effectively stop infected cells from infecting other cells.
Oral supplementation of zinc alone is not sufficiently effective since zinc cannot move easily across the cell wall. It needs another compound to provide transportation. The second compound is called a zinc ionophore. The application of zinc with an ionophore has demonstrated improved outcomes in patients hospitalized with COVID.
Research has identified several zinc ionophores, including chloroquine, hydroxychloroquine, quercetin, and EGCG. Scientists have suggested that several of the terpenes in black seed oil, such as nigellimine, are similar in structure to chloroquine. They hypothesize that this may mean they can function in a similar manner as a zinc ionophore.
Thus, recent data has shown that the active ingredients found in black seed oil may act as a zinc ionophore and may help block the ACE2 receptors the virus uses to infect cells.
Black Seed Oil
The immune-modulating activities of black seed oil help to regulate the immune system and maybe another pathway in the treatment for COVID-19. In addition to the studies using black seed oil, researchers have separated the bioactive ingredients in black seed oil and evaluated their potential benefit against SARS-CoV-2.
A data review on thymoquinone was published in February 2021, in which the researchers reviewed the bioactivity of the compound as revealed in past research. They wrote that thymoquinone increased the activity and number of natural killer cells, macrophages, lymphocytes, and cytokines suppressors.
Additionally, they cite past research that showed thymoquinone had antiviral potential against other viruses, including human immunodeficiency virus, other coronaviruses, Epstein-Barr virus, cytomegalovirus, and hepatitis C. In addition, they reviewed an Egyptian study in which thymoquinone demonstrated antiviral activity in a strain of SARS-CoV-2 isolated in patients and the inhibitory effect it has on the viral protease, which may reduce viral replication.
One study from Saudi Arabia evaluated the effectiveness of black seed oil as a supplement in patients with mild COVID-19 who were between the ages of 18 and 65. The intervention group received 500 mg of soft gel capsules twice daily for 10 days in addition to their standard treatment.
Initial results were published on Clinical Trials. The primary outcome measured was the percentage of participants who showed clinical recovery within 14 days after treatment began. The team reported 62.1 percent of those receiving the black seed oil demonstrated recovery from mild COVID-19 while 36 percent of the control group recovered within 14 days.
Consider Oil for Short-Term Use
The Front Line COVID-19 Critical Care Alliance (FLCCC) lists black seed oil as an alternative for the prevention and treatment of COVID-19. They stress there is no “magic bullet” for COVID-19, yet:
“A number of therapeutic agents have shown great promise for both the prevention and treatment of this disease including Ivermectin, Vitamin D, quercetin, melatonin, fluvoxamine, corticosteroids, curcumin (turmeric), Nigella sativa, and antiandrogen therapy.”
The team recommends taking N. sativa with honey as they both have antimicrobial, antiviral, immunomodulatory, and anti-inflammatory effects with proven safety profiles. They list N. sativa and honey in the prevention protocol for children and adolescents, and as an alternative for first-line treatment in the early treatment protocol at home.
While short-term use of black seed oil may be efficacious in the treatment of COVID-19, long-term use for prevention may have other unwanted effects. One study of the chemical composition of black seed oil shows that the majority of fatty acids are from linoleic acid, an omega-6 polyunsaturated fat. A wide range of research suggests linoleic acid is likely the leading contributing cause of virtually all chronic diseases we have encountered in the past century.
If you are interested in using black seed oil, consider the extracts of the bioactive ingredients and not the whole oil.
If you are seeking an alternative for prevention and treatment, consider a combination of quercetin and zinc. Quercetin also has antiviral properties and is a zinc ionophore. While safe to take for about two weeks when you’re ill, it is important you are careful with zinc supplements as you may offset your zinc/copper balance and negatively affect your immune system.