Buy black seed oil for a range of uses from reducing mild allergy symptoms to promoting hair growth. It is widely used as a beauty treatment and skin care product because it can soothe eczema and psoriasis. Black seed oil is also believed to promote a healthy metabolism and increase hair growth.

The seeds of the Nigella sativa plant (also known as black cumin, black caraway, and kalonji) have long been used in cooking and in traditional medicine. But recent research suggests the plant may be able to help treat a variety of health problems, including asthma and inflammatory skin conditions like eczema. Other studies show it might be helpful in treating obesity and diabetes, as well as lowering cholesterol and blood fats called triglycerides.

Black seed oil is packed with antioxidants, as well as a chemical called thymoquinone, which appears to have cancer-fighting powers. In one study, thymoquinone shrank tumors in rats. But more research is needed to see if it could work in humans, too.

Short-term use of black seed oil seems to be safe for most people, but it’s important to talk with your doctor before trying this or any other herbal supplement. The seeds may interact with certain medications, such as immune system-suppressing drugs or those used to treat high blood pressure and diabetes. They also may slow your blood’s ability to clot, so you should avoid them if you’re taking blood thinners. Also, if you have kidney or liver disease, don’t take black seed oil.