12 Benefits of Black Seed Oil
This article will look at the scientific evidence behind some benefits of black seed oil and explore possible contraindications.
Although there is limited research on the direct effects of black seed oil for hair, manufacturers add it to many hair products.
Thymoquinone is a predominant component of the oil that has antioxidant, anti-microbial, and anti-inflammatory properties. It may help create a scalp environment conducive to hair health and growth. Also, its antibacterial and antifungal properties can help resolve skin imbalances on the scalp and body such as eczema and psoriasis.
A 2014 study found that black seed oil mixed with coconut oil increased hair growth when study participants applied it to their scalp three times a day.
Because both of these studies used a combination of ingredients, we cannot know with certainty that the effects were due to the black seed oil.
People interested in healthy weight loss may find benefits from black seed oil.
In a 2021 review, multiple studies revealed that the consumption of black seed oil influenced weight loss through various mechanisms, including:
- inhibition of pancreatic enzymes, which break down fat and carbohydrates
- upregulation of a gene called uncoupling protein-1 (UCP-1) that increases brown adipose tissue, which promotes fat burning and thermogenesis
- modulation of genes involved in fat and glucose metabolism
This 2021 review included test tube or cellular studies, rodent studies, and a few human studies. More human-controlled studies are needed to confirm the results.
There is also overlap between N. Sativa’s anti-diabetic effects and weight loss. For instance, black seed oil has been shown to cause partial regeneration of pancreatic beta cells, lower serum insulin levels, and decrease blood glucose. Proper blood sugar control and enhanced insulin sensitivity can help with weight management.
A 2020 study comprising 45 women with obesity or overweight showed that taking 2,000 milligrams (mg) of black seed oil daily for 8 weeks decreased appetite and reduced waist circumference, body fat, and body mass index.
Also, a 2015 study evaluated the effects of black seed oil in 84 women with obesity. Those who consumed 3 grams (g) of black seed oil per day for 8 weeks and followed a low calorie diet had greater reductions in body weight and belly fat than those who followed just a low calorie diet.
Furthermore, a 2018 meta-analysis of 11 studies found that black seed supplements could modestly reduce belly fat, body weight, and body mass index. The authors did state that there is a lack of high-quality human studies and that the studies included in the meta-analysis contained a lot of variation.
Many studies have investigated the anti-inflammatory effects of N. Sativa and its bioactive constituents.
Research suggests that inflammation is an underlying driver of many different diseases, so black seed oil’s anti-inflammatory properties may be partly responsible for its role in the treatment of a wide range of conditions.
A 2021 meta-analysis of 10 randomized control trials showed that consumption of black seed oil reduced markers of inflammation and increased endogenous antioxidant levels.
Similarly, a 2020 meta-analysis of 12 randomized control trials found that black seed oil consumption significantly reduced C-reactive protein (CRP) and malondialdehyde, which are markers of systemic inflammation and oxidative stress, respectively. Blood antioxidant levels were also significantly increased.
Authors of the 2020 meta-analysis stated that the number of trials in the review was limited so more studies with larger sample sizes and longer follow-up periods would be necessary to confirm the anti-inflammatory and antioxidant effects of N. sativa.
A 2019 systemic review of seven studies found that N. sativa may help improve several markers of blood sugar control, including insulin levels, fasting blood sugar, and post-prandial blood sugar after a meal.
Similarly, a 2016 systematic review of 23 studies found that black seed could be promising at reducing fasting blood sugar and decreasing levels of hemoglobin A1C, a measure of blood sugar levels over a 3 month period. However, there were mixed results.
Moreover, a 2019 meta-analysis of 17 clinical trials demonstrated that black seed oil was more efficacious than black seed powder at reducing fasting blood sugar levels.
Black seed oil may help lower blood pressure, but study results are mixed. A 2016 systematic review analyzed four clinical trials where black seed oil had beneficial effects on blood pressure and five studies that saw no benefit.
Additionally, a 2017 clinical trial showed that 57 patients who received 2 g of black cumin every day for one year had a reduction in systolic, diastolic, and mean arterial blood pressure, heart rate, and LDL-c. However, the study was not randomized and there could have been allocation bias. The sample size could also not be maintained.
Furthermore, a 2017 review of two human studies on participants who were healthy or with mild hypertension showed the possible favorable effects of black seed oil on blood pressure. However, study subjects may have different results than those with serious HTN or metabolic syndrome.
Experiments from cell culture, animal models, and one human intervention from a 2021 review suggest that thymoquinone in black seed oil may reduce inflammation in the brain.
Thus, black seed oil may help protect against brain disorders such as Parkinson’s disease or Alzheimer’s disease, in which inflammation of brain tissue may play a role.
While this research may sound compelling, there is limited evidence in high quality human clinical trials.
A 2013 study investigated the therapeutic potential of 2% N. Sativa ointment applied topically twice a day for 4 weeks in patients with hand eczema compared to eucerin and betamethasone.
The results showed that N. sativa ointment had the same efficacy as betamethasone in reducing the severity of hand eczema.
A 2018 study investigated the effects of black seed oil on psoriasis-like skin lesions in male rats. Researchers applied a medication called imiquimod (IMQ) to induce the lesions.
The results of this study demonstrated that topical use of black seed oil strongly inhibited psoriasis-like inflammation and alleviated all epidermal and dermal changes observed after IMQ application. This allows us to conclude that black seed oil may be beneficial as an adjuvant topical therapy for treating psoriasis.
Black seed oil may accelerate wound healing due to the anti-inflammatory, antioxidant, and antibacterial properties of thymoquinone.
A 2020 review found that 6 out of 7 studies where N. Sativa and thymoquinone aided in wound healing.
Vitiligo is a hypopigmentation disorder that causes white spots due to the loss of skin pigment cells.
In a 2014 study, researchers compared fish oil and black seed oil on the application of vitiligo lesions. While the authors of this study found that both treatments were effective, black seed oil was more effective than fish oil.
Studies with both human males experiencing infertility and rodents have found that black seed oil can boost sperm count and increase sperm motility.
The many therapeutic properties, such as antioxidant and anti-inflammatory properties, attributed to the oil likely help protect sperm from oxidative damage. However, human clinical trials on this are limited, and some recent research on this focused on male mice only.
There is currently no consensus on dosage, but one 2021 study suggested that adults should limit usage to 900 mg of black seed oil or 48.6 mg of thymoquinone daily in order to decrease the risk of side effects.
Discuss with your doctors the right dosage and whether it is safe for you to take.
Due to limited research, black seed oil should not be taken during pregnancy or lactation. Consult with your doctor to discuss whether black seed oil is right for you.
Additionally, thymoquinone may inhibit drug-metabolizing cytochrome P450 enzymes in the liver, so a person should refrain from using the oil while taking a medication that may be consequently affected.
Medications that can help treat diabetes, cholesterol, and blood pressure may also be metabolized in the cytochrome P50 pathway. Talk to your doctor about how black seed oil might interact with your own medication.
Black seed oil has been used for thousands of years in folklore medicine to treat a wide range of conditions. There is now emerging scientific evidence in human, animal, and cell culture studies corroborating some of its health benefits.
However, more high quality randomized control trials for some of its purported health claims are still needed for more robust evidence.