Supplements Antioxidants Black Seed Oil By Alena Clark, PhD Alena Clark, PhD Verywell Health's LinkedIn Alena Clark, PhD, is a registered dietitian and experienced nutrition and health educator Learn about our editorial process Updated on July 15, 2022 Medically reviewed by Allison Herries, RDN Medically reviewed by Allison Herries, RDN Allison Herries, RDN, is a registered dietitian focused on preventing and managing chronic diseases through healthy lifestyle changes. Learn about our Medical Expert Board Print Table of Contents View All Table of Contents Uses Side Effects Precautions Dosage Toxicity Interactions Frequently Asked Questions How to Store Sources & What to Look For Black seed oil is a supplement extracted from the seeds of Nigella sativa, a flowering plant that grows in Asia, Pakistan, and Iran. Black seed oil has a long history dating back over 2,000 years. Black seed oil contains the phytochemical thymoquinone, which can act as an antioxidant. Antioxidants detoxify harmful chemicals in the body called free radicals. This article discusses the potential uses, risk factors, and side effects of taking the supplement. Dietary supplements are not regulated in the United States, meaning the Food and Drug Administration (FDA) does not approve them for safety and effectiveness before products are marketed. When possible, choose a supplement that has been tested by a trusted third party, such as USP, ConsumerLabs, or NSF.However, even if supplements are third-party tested, that doesn't mean they are necessarily safe for all or effective in general. Therefore, it is important to talk to your healthcare provider about any supplements you plan to take and check-in about potential interactions with other supplements or medications. Supplement Facts Active ingredient(s): ThymoquinoneAlternate name(s): Black cumin seed oil, Kalonji oil, Nigella sativa oilLegal status: Not regulated by the FDASuggested dose: More research is needed on dosage for certain ages and conditionsSafety considerations: Use caution with certain drugs, herbs, and supplements Uses of Black Seed Oil Supplement use should be individualized and vetted by a healthcare professional, such as a registered dietitian nutritionist, pharmacist, or healthcare provider. No supplement is intended to treat, cure, or prevent a disease. Although research on the health effects of black seed oil is relatively limited, there is some evidence that it may offer potential benefits. Here's a look at several key findings from available studies. Type 2 Diabetes Black seed oil may benefit some people with type 2 diabetes, according to a 2017 review published in the Journal of Pharmacopuncture. Researchers reviewed four randomized, double-blind, placebo-controlled clinical trials with people who had taken black seed as oil, tea, or seeds. Results indicated that participants had a decrease in their fasting blood glucose. It is important to note that in most studies, black seed oil was consumed in addition to using oral diabetes medications, eating a healthy diet, and exercising. A more recent study from 2020 aimed to evaluate the effect of black seed oil on inflammation, fasting blood glucose, and lipid profile in people with type 2 diabetes. The results also showed significant reductions in fasting blood glucose levels among those who received black seed oil capsules versus the placebo group. Rheumatoid Arthritis According to a small study published in Immunological Investigations in 2016, black seed oil may help manage rheumatoid arthritis (RA). In this randomized, double-blinded placebo-controlled study, 43 women with mild-to-moderate RA took black seed oil capsules or a placebo every day for one month. Compared to the placebo group, those who used black seed oil reported reductions in: Arthritis symptoms (as assessed by a clinical rating scale) Blood levels of inflammatory markers The number of swollen joints Geo-grafika/Getty Images Allergies & Nasal Inflammation Black seed oil shows promise for treating allergies. For instance, in a 2011 clinical trial with 66 people published in the American Journal of Otolaryngology, when participants used black seed oil for two weeks, it reduced nasal symptoms including: Nasal congestionItchy noseRunny noseSneezing Another report published in 2018 analyzed data to determine if black seed oil could help treat sinusitis. Study authors concluded that the oil has multiple therapeutic effects, including: Anti-inflammatory Antioxidant Antihistaminic Immune-modulator (something that affects the immune system) Antimicrobial Analgesic What to Know About Perennial Allergic Rhinitis Obesity Black seed oil may reduce risk factors in women who are obese, according to a study. For the study, women consumed Nigella sativa oil or a placebo while following a low-calorie diet for eight weeks. At the study's end, the following levels had decreased by more in the group that took the Nigella sativa oil: Weight Waist circumference Triglyceride Another eight-week study enrolled sedentary women with excess weight and looked at the combination of aerobic exercise with black seed oil supplementation. In the study, one group took black seed oil, and another took a placebo; both used aerobic exercise. Researchers found that the treatment combination of diet, exercise, and black seed oil provided benefits, including lowering weight and cholesterol levels. Still, the authors concluded that further studies with a larger sample size and diet assessment are needed. Using Black Seed to Lower Cholesterol Other Uses of Black Seed Oil While black seed oil has been studied in human, lab, and animal studies for the below conditions, more research is needed. Please discuss your use of black seed oil with your registered dietitian nutritionist, pharmacist, or healthcare provider before using it for any of the following: Allergies Headaches High blood pressure Digestive disorders Boosting the immune system Reducing inflammation Fighting infections Acne Dry hair Psoriasis Hair growth Dry skin What Are the Side Effects of Black Seed Oil? Consuming a supplement like black seed oil may have potential side effects. These side effects may be common or severe. Common Side Effects Very little is known about the long-term safety of black seed oil or how safe it is in amounts higher than what's typically found in food. However, some studies have found risks associated with black seed oil, including: Toxicity: A component of black seed oil known as melanthin (poisonous component) may be toxic in larger amounts. Allergic reaction: Applying black seed oil directly to the skin may cause an allergic skin rash known as allergic contact dermatitis in some individuals. In a case report, one person developed fluid-filled skin blisters after applying Nigella sativa oil to the skin. However, they also ingested the oil, so it's possible that the blisters were part of a systemic reaction (such as toxic epidermal necrolysis). Bleeding risk: Black seed oil may slow blood clotting and increase the risk of bleeding. Therefore, you should not take black seed oil if you have a bleeding disorder or take medication that affects blood clotting. In addition, stop taking black seed oil at least two weeks before a scheduled surgery. For these reasons, be sure to talk with your healthcare provider if you're considering taking black seed oil. In addition, remember that black seed oil is not a replacement for conventional medical care, so avoid stopping any of your medications without speaking with your healthcare provider. Precautions Children and people who are pregnant or lactating should not take black seed oil remedies due to the lack of research into their long-term safety. Dosage: How Much Black Seed Oil Should I Take? Always speak with a healthcare provider before taking a supplement to ensure that the supplement and dosage are appropriate for your individual needs. Adults most often use black seed oil in doses of 1 to 2.5 grams by mouth daily for four to 12 weeks. Black seed powder has most often been used in doses of 1 to 2 grams by mouth daily for eight to 12 weeks. Speak with a healthcare provider to determine what dose might be best for a specific condition. What Happens If I Take Too Much Black Seed Oil? As a rule of thumb, never take more than the manufacturer's recommended dosage. If you experience side effects of any sort, stop taking black seed oil and call your healthcare provider. Interactions It is essential to carefully read the ingredient list and nutrition facts panel of a supplement to know which ingredients and how much of each ingredient is included. Please review this supplement label with your healthcare provider to discuss any potential interactions with foods, other supplements, and medications. Drugs Interactions It's also possible that black seed oil may interact with many common drugs, including: Drugs that treat high blood pressure, such as Norvasc (amlodipine) Immunosuppressants Diabetes drugs Serotonergic drugs (drugs that increase serotonin levels in the brain) Anticoagulant drugs (drugs that slow blood clotting) Sedative drugs Diuretic drugs (also known as water pills) Herb and Supplement Interactions It's also possible that black seed oil may interact with many common herb and supplement interactions, including: Herbs and supplements that might lower blood pressure (e.g., casein peptides, L-arginine, niacin, and stinging nettle) Herbs and supplements that might lower blood sugar (e.g., aloe, bitter melon, cassia cinnamon, chromium, prickly pear cactus) Herbs and supplements that might slow blood clotting (e.g., garlic, ginger, ginkgo, nattokinase, and Panax ginseng) Herbs and supplements with sedative properties (e.g., hops, kava, L-tryptophan, melatonin, and valerian) Herbs and supplements with serotonergic (affecting serotonin in the brain) properties (e.g., 5-HTP, L-tryptophan, SAMe, and St. John's wort). Iron: Black seed oil might increase the amount of iron the body absorbs. Frequently Asked Questions What is black seed oil used for? Some people use black seed oil supplements to treat certain health conditions, including arthritis, allergies, asthma, and diabetes, and maintain a healthy weight. While some studies support health claims, most are small, and more research is needed. Are there some individuals who should not take black seed oil? Children and pregnant or lactating individuals should not take black seed oil. Certain drugs, herbs, and supplements can have interactions. Always consult your healthcare provider before starting a supplement. How much black seed oil should I take? Adults most often use black seed oil in doses of 1 to 2.5 grams by mouth daily for four to 12 weeks. However, you should always consult with your healthcare provider first to determine whether the supplement and dosage are appropriate for you. How to Store Black Seed Oil Store black seed oil according to the manufacturer's directions. Discard as indicated on the packaging. Sources of Black Seed Oil & What to Look For See below for more information on food and supplement sources of black seed oil. Food Sources of Black Seed Oil Black seed oil has been used in many countries as a spice and food preservative. It can be purchased in stores as an oil or powder. Black Seed Oil Supplements Black seed is often sold as a powder, tea, supplement, or oil. When buying a supplement, don't be fooled by claims that it can cure or treat any specific disease. Under the FDA labeling laws, it is illegal for manufacturers to make such claims, which are rarely supported by clinical evidence. Recap The FDA does not regulate black seed oil supplements, so use caution when choosing a supplement. Avoid those that make claims about treating health conditions, and look for certified cold-pressed products. Summary Some people use black seed oil supplements to treat certain health conditions, including arthritis, allergies, asthma, and diabetes, and maintain a healthy weight. While some studies support health claims, most are small, and more research is needed. As a supplement, the FDA does not regulate black seed oil. You should use caution and work with your healthcare provider to determine if it is right for you and at what dosage. 15 Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Gali-Muhtasib H, Roessner A, Schneider-Stock R. Thymoquinone: a promising anti-cancer drug from natural sources. Int J Biochem Cell Biol. 2006;38:1249-1253. doi:10.1016/j.biocel.2005.10.009 Shafiq H, Ahmad A, Masud T, Kaleem M. Cardio-protective and anti-cancer therapeutic potential of Nigella sativa. Iran J Basic Med Sci. 2014;17(12):967-979. Tavakkoli A, Mahdian V, Razavi BM, Hosseinzadeh H. Review on the clinical trials of black seed (Nigella sativa) and its active constituent. J of Pharmacopuncture. 2017;20(3):179-193. doi:10.3831/kpi.2017.20.021 MedlinePlus. Black seed. Kooshki A, Tofighiyan T, Rastgoo N, Rakhshani MH. Effect of Nigella sativa oil supplement on risk factors for cardiovascular diseases in patients with type 2 diabetes mellitus. Phytotherapy Research. 2020. doi:10.1002/ptr.6707 Kheirouri S, Hadi V, Alizadeh M. Immunomodulatory effect of nigella sativa oil on T lymphocytes in patients with rheumatoid arthritis. Immunol Invest. 2016;45(4):271-283. doi:10.3109/08820139.2016.1153649 Nikakhlagh S, Rahim F, Aryani FH, et al. Herbal treatment of allergic rhinitis: the use of nigella sativa. Am J Otolaryngol. 2011;32(5):402-407. doi:10.1016/j.amjoto.2010.07.019 Mahboubi M. Natural therapeutic approach of Nigella sativa (black seed) fixed oil in management of sinusitis. Integr Med Res. 2018;7(1):27–32. doi:10.1016/j.imr.2018.01.005 Mahdavi R, Namazi N, Alizadeh M, Farajnia S. Effects of Nigella sativa oil with a low-calorie diet on cardiometabolic risk factors in obese women: a randomized controlled clinical trial. Food Funct. 2015;6(6):2041-2048. doi:10.1039/c5fo00316d Farzaneh E, Nia FR, Mehrtash M, Mirmoeini FS, Jalilvand M. The effects of 8-week Nigella sativa supplementation and aerobic training on lipid profile and VO2 max in sedentary overweight females. Int J Prev Med. 2014;5(2):210–216. Kooti W, Hasanzadeh-noohi Z, Sharafi-ahvazi N, Asadi-samani M, Ashtary-larky D. Phytochemistry, pharmacology, and therapeutic uses of black seed (Nigella sativa). Chin J Nat Med. 2016;14(10):732-745. doi:10.1016/S1875-5364(16)30088-30087 Salem EM, Yar T, Bamosa AO, Al-Quorain A, Yasawy MI, Alsulaiman RM, et al. Comparative study of Nigella Sativa and triple therapy in eradication of Heliobacter Phylori in patients with non-ulcer dyspepsia. Saudi J Gastroenterol. 2010;16(3):207-214. doi:10.4103/1319-3767.65201 Okasha EF, Bayomy NA, Abdelaziz EZ. Effect of topical application of black seed oil on imiquimod-induced psoriasis-like lesions in the thin skin of adult male albino rats. Anat Rec (Hoboken). 2018;301(1):166-174. Ijaz H, Tulain UR, Qureshi J, et al. Review: Nigella sativa prophetic medicine): a review. Pak J Pharm Sci. 2017;30(1):229-234. Steinmann A, Schatzle M, Agathos M, Brett R. Allergic contact dermatitis from black cumin (Nigella sativa) oil after topical use. Contact Dermatitis. 1997;36:268-269. doi:10.1111/j.1600-0536.1997.tb00219.x Additional Reading Taxon: Nigella sativa L. Taxonomy. GRIN-Global Web v 1.10.3.6. Ahmad A, Husain A, Mujeeb M, et al. A review on therapeutic potential of Nigella sativa: A miracle herb. Asian Pac J Trop Biomed. 2013;3(5):337–352. doi:10.1016/S2221-1691(13)60075-1 Beheshti F, Khazaei M, Hosseini M. Neuropharmacological effects of Nigella sativa. Avicenna J Phytomed. 2016;6(1):104–116. By Alena Clark, PhD Alena Clark, PhD, is a registered dietitian and experienced nutrition and health educator Originally written by Cathy Wong Cathy Wong Cathy Wong is a nutritionist and wellness expert. Her work is regularly featured in media such as First For Women, Woman's World, and Natural Health. Learn about our editorial process See Our Editorial Process Meet Our Medical Expert Board Share Feedback Was this page helpful? Thanks for your feedback! What is your feedback? Other Helpful Report an Error Submit