11 benefits of black seed oil

In the world of traditional medicine, Nigella sativa, also known as black seed or black cumin, is like royalty. N. sativa is a flowering plant native to India, northern Africa, and southwest Asia. Black cumin oil (made from the seeds of Nigella sativa) has been used for centuries as a remedy for everything from mental illness to heart disease. Scientific studies have confirmed that thymoquinone, a compound found in black seed oil, is packed with antioxidants, along with antimicrobial, anti-inflammatory, and anti-cancer activity.

Black seed oil can be ingested directly, added to supplements, or used in skin and hair products. Some black seed oil products and methods are more beneficial than others. While black seed oil has many health benefits, more research is needed to understand the exact dose, side effects, and preparation to reap those benefits.

Black seed oil benefits

Read on to learn how black seed oil works and how to incorporate it into your regimen to reap the following health benefits:

1. Soothe chronic skin conditions
2. Manage diabetes
3. Accelerate weight loss
4. Lower blood pressure
5. Improve brain health
6. Reduce inflammation
7. Improve creaky joints
8. Reduce cancer cells
9. Enhance sperm quality
10. Boost scalp and hair health
11. Support wound healing

1. Soothe chronic skin conditions

Black seed oil is anti-inflammatory, antibacterial, and antifungal. That’s great news for irritated skin. Topical application of black seed oil or skin care products containing black seed oil could help soothe symptoms of several chronic skin conditions.

“For centuries, nations have used this extract as a treatment for things like eczema, psoriasis, and acne,” says Erika Luren, MA, MS, NP, a nurse practitioner and owner of Parasol Aesthetics, Dermatology & Wellness in Las Vegas, Nevada. “Such uses would appear logically motivated as all of the conditions have an inflammatory component.”

In one four-week study, researchers found that applying black seed oil twice daily was as effective as corticosteroid cream at improving eczema symptoms. Other studies have shown that topical black seed oil can improve psoriasis symptoms and reduce acne lesions by up to 78%.

Black seed oil is no magical cure for skin conditions, especially if the cause is linked to your diet, allergies, or an autoimmune disease. However, the science is clear that this plant oil can at least help your skin look and feel better while you pinpoint a diagnosis and treatment plan.

2. Manage diabetes

Anyone with diabetes knows that blood sugar management is critical to good health. Consuming black seed oil (such as in food) or taking black seed oil supplements may help. 

In one study, patients at risk for diabetes who took 1.5 or 3 mL (less than a teaspoon) of black seed oil each day for 20 days had lower blood glucose levels at the end of the study than the placebo group. More studies are needed to understand the best dose to help manage diabetes, but the preliminary results are promising.

3. Accelerate weight loss

“A study published in 2021 showed promising results for the effects of black seed oil on weight loss,” says Kimberley Wiemann, MS, RDN, a Long Island, NY-based registered dietitian. “The study showed an improvement in Body Mass Index (BMI), a decrease in body fat, body fat percent, weight, and visceral fat mass. Study participants had increased feelings of fullness and decreased appetite.”

However, Wiemann warns that the small study size and short duration mean more research is needed to prove the weight loss benefits of black seed oil are universal or sustainable. 

4. Lower blood pressure

Nearly half of American adults have hypertension, the medical term for high blood pressure. People with high blood pressure can help manage the condition with lifestyle changes like eating a healthy diet, ditching smoking or vaping, and moving their bodies daily. But taking black seed oil could help with hypertension, too. Research suggests that taking 2.5 mL twice daily could help lower high blood pressure. Most people with true hypertension need prescription antihypertensives to control blood pressure adequately. 

5. Improve brain health

On top of black seed oil’s health benefits for blood sugar and blood pressure, this plant extract has perks for your brain. N. sativa has neuroprotective properties, which means that consuming it regularly might help reduce your risk of neurological issues such as depression and memory loss.

6. Reduce inflammation

Why is it that some plants get touted as a remedy for wildly different conditions? How can one medicinal oil be used to treat asthma and eczema? Because many irritating, painful, or obstructive conditions have one thing in common: inflammation.

Luren says black seed oil’s anti-inflammatory effects are a key reason this ingredient is used in many skincare products. It makes sense: If inflammation is marked by swelling (asthma, anyone?) and redness or irritation (the case with many skin conditions), ingesting or applying an anti-inflammatory oil can help alleviate all those symptoms.

7. Improve creaky joints

Some people feel stiff and achy in the mornings. Others have rheumatoid arthritis (RA), an autoimmune disease that causes painful joint swelling that inhibits movement. In both cases, anti-inflammatory ingredients like black seed oil can help decrease pain and make movement easier. 

In fact, Nigella sativa offers a double boost to RA patients: In addition to reducing inflammation, black seed oil helps regulate the immune system, leading to significant improvement in RA symptoms, per a 2011 clinical trial in Phytotherapy Research.

8. Reduce cancer cells

Let’s be clear: N. sativa oil is no cure for cancer. However, thymoquinone, the active compound in the black cumin seed, has been shown to reduce the growth of certain cancer cells. The dosage and type of study—animal studies or test tube studies—vary, so more research is needed. Still, results are promising, and black seed oil could be a component of natural therapies against cancer in the future. If you have cancer, you are strongly encouraged to consult with your oncologist for the best treatment regimen for you.

9. Enhance sperm quality

There are many possible causes of male infertility. For men struggling to conceive because of low sperm quality, black seed oil may help.

Both traditional medicine and human studies reflect the effectiveness of black seed oil in improving abnormal sperm quality. A placebo-controlled 2024 study in Iran found that men who took black seed in liquid form twice a day for two months had improved sperm count, motility, and volume compared to those who received a non-medicinal oil. If you and your partner are encountering infertility, consult with a reproductive endocrinologist or urologist for further workup and treatment. 

10. Boost scalp and hair health

Similar to how black seed oil benefits your skin, Luren says applying black seed oil to your scalp might support healthy hair growth. However, she says there is little research to confirm the true efficacy of black seed oil in hair care products.

She adds that while black cumin oil’s antioxidant, anti-inflammatory, and antimicrobial effects can boost scalp health, improving hair growth, it might not be as simple as slathering oil on top of your head. “When we lean into the biochemistry of the oil manufacturing itself, there is a quandary as to how well the molecular size of the sative and the vehicle it is in penetrate the scalp,” she explains. In other words, topical use of black seed oil might not be able to penetrate the hair follicles and give you longer locks.

11. Support wound healing

A systematic review of Nigella sativa suggests that the oil from these tiny black seeds might speed up, or at least support, wound healing. Once again, it’s all thanks to thymoquinone.

Thymoquinone’s anti-inflammatory, antioxidant, and antibacterial qualities make it a stellar ingredient for wound-healing balms or ointments. Fighting bacteria and oxidative stress helps prevent wound infection. Soothing inflammation helps treat unpleasant wound symptoms.

Black seed oil side effects

“Black seed oil may have many benefits for the body, skin, and hair,” says Luren. “However, as with any alternative therapy, research is limited as to its full effectiveness and long term safety.”

Both Luren and Wiemann report that serious adverse effects from black seed oil are not common. However, Wiemann says some people have experienced side effects such as:

• Gastrointestinal discomfort ( such as bloating or diarrhea)
• Low blood pressure
• Allergic reaction

Always consult your healthcare provider about potential side effects before taking a new supplement, even a plant-based oil. While Wiemann says there are no known supplement or medication interactions with black seed oil, the potential for lowering blood pressure could be serious for someone who is already taking blood pressure medication. Before elective surgeries, stop taking all supplements as they may hinder blood clotting or healing. 

“The other medications that black seed oil may interact with causing increased or decreased effects are antidiabetic medications, thyroid medication, diuretics, anti-clotting medications, sedatives, and mood stabilizer therapies,” Luren adds.

How to take black seed oil safely

Whether you want to take black seed oil to whittle your waist circumference, combat hair loss, or for its therapeutic effects on other health conditions, it’s important to check with your doctor first. Once you’ve been given the green light to add this medicinal plant oil to your daily supplemental routine, look for quality black seed oil, black seed oil capsules, or black seed oil dietary supplements from a brand you trust.

Safety and quality considerations:

• Cold-pressed oil is extracted without heat, which means it potentially retains more nutrients than chemically extracted or heat-extracted black seed oil.
• Generally, starting with the smallest dose possible is best to observe how your body reacts.
• Ingest black seed oil no more than twice daily. Most human trials with black seed oil used very low doses (less than a teaspoon) twice per day. 

Finally, remember that black seed oil is not a magic bullet. “It is important to remember that a supplement such as this cannot be a replacement for a healthy diet and exercise,” says Wiemann.