Black seeds are also known as black caraway, black cumin, kalonji, and black onion seeds.
They come from Nigella sativa, a small plant with pale purple, blue, or white flowers that grows in Eastern Europe, Western Asia, and the Middle East.
People have used the tiny black seeds of the fruits of N. sativa as a natural remedy for thousands of years. The seeds can also flavor curries, pickles, and bread in a similar way to cumin or oregano.
The black seed oil contains thymoquinone, which is an antioxidant and anti-inflammatory compound that may also have tumor-reducing properties.

Benefits of black seed oil

Scientists with a range of specialties have researched the possible benefits of black seed oil.
However, it is important to note that many studies to date have used cells or animals as models, and there is limited research available on the effects of black seed oil in humans.

Benefits for weight loss

Research has shown that black seed supplementation can help lower people’s body mass index (BMI). The study participants did not report any severe side effects from taking this supplement.
A systematic review published in the Journal of Diabetes & Metabolic Disorders in 2013 found that black seed oil could be effective in tackling obesity.

Benefits for the skin

Black seed oil may be beneficial for people with the following skin conditions:
Black seed oil may also hydrate hair, soften skin, and act as a moisturizer, although there is a lack of scientific evidence to confirm these benefits.

Benefits for health conditions

Black seed oil may also be beneficial for some health conditions, including the following:

Cancer

Recent studies have shown that the thymoquinone in black seed oil can influence programmed cell death, or apoptosis, in several types of cancer cells. These include brain cancer, leukemia, and breast cancer cells.

However, much of the research on the effects of black seed oil on cancer uses cells rather than live humans, so researchers do not yet know how effective the oil may be to treat people with cancer.

Liver and kidney function

According to a 2013 study on rats, black seed oil may reduce liver and kidney disease complications and improve organ structures. Researchers do not know if these effects would also occur in humans.

Diabetes

According to an article in the Journal of Endocrinology & Metabolism, black seed oil may have anti-diabetic properties and improve blood sugar levels. Again, this study used animal models, so more research is necessary to confirm the effectiveness of the oil in humans.

Infertility

A placebo-controlled clinical trial on men with abnormal sperm and infertility has found that black seed oil can improve sperm movement and increase sperm count and semen volume