black seed oil

Black seed oil is pressed from the seeds of Nigella sativa, a flowering plant also called black cumin or black caraway that grows in parts of Asia, the Middle East, and North Africa. The seeds and their oil have a long history of culinary and traditional use, and thymoquinone is often described as a main compound of interest. It is sold in the US as a dietary supplement (oil or capsules), a category the FDA does not review for effectiveness before sale.

Rigorous evidence in people is limited, and no NIH Office of Dietary Supplements or NCCIH consumer fact sheet establishes that black seed oil treats any condition. The one place a US government authority addresses it directly is an NCCIH page on hepatitis C, which lists black cumin (Nigella sativa) only among products that have undergone "preliminary studies" and states that "the limited research on these products hasn't produced convincing evidence that they're helpful for hepatitis C." That same page notes no dietary supplement has been shown to be effective for hepatitis C. Most other research is preliminary or limited to cell and animal studies, so claims that black seed oil treats allergies, diabetes, high cholesterol, or other diseases are not supported by strong evidence.

There is no established or government-recommended dose for black seed oil, and amounts in products vary widely. Because supplements are not standardized and the right amount, if any, is unknown, you should not assume that any dose is proven safe or effective. Talk to your doctor or pharmacist before starting black seed oil, especially if you are pregnant or breastfeeding, have a health condition, or take any medicines.

No authoritative US government safety review specific to black seed oil supplements is available, so its long-term safety is not well established. As with any supplement, product quality and purity can vary because the FDA does not approve dietary supplements for safety and effectiveness before they are sold. Pregnant or breastfeeding people, children, and anyone with a medical condition should be especially cautious and consult a clinician first.

Reported reactions in everyday use can include digestive upset and, when the oil is applied to the skin, allergic or contact reactions in some people, though comprehensive government data on side effects is lacking. Because rigorous safety monitoring is limited, the full range of possible side effects is not well characterized. Stop use and seek medical care if you have signs of an allergic reaction such as rash, swelling, or trouble breathing.

High-quality government guidance on black seed oil drug interactions is not available. Because it has been studied for possible effects on blood sugar and blood pressure, it could in theory add to the effects of diabetes or blood-pressure medicines; it may also theoretically interact with medicines processed by the liver or with drugs that affect bleeding. These concerns are theoretical rather than established. Tell your doctor and pharmacist about all supplements you take so they can check for interactions with your prescriptions.