Black cumin seeds have been used for centuries in the Middle East, Mediterranean, and India to treat a variety of ailments, and have been adopted for homeopathic use in Europe and other nations as well. Both the seeds and potent extracts can be found for sale in natural food stores, and doctors who practice complementary alternative medicine may prescribe then for a wide variety of conditions. The unique nutritional composition of black cumin seeds, which includes numerous essential fatty acids, appears to support the immune system, improve the skin, help with respiratory ailments, and address digestive conditions.

Nigella sativa is the scientific name for the plant on which black cumin seeds grow, and it is a member of the buttercup family. They are not related to the common cooking herb, cumin, from the Cuminum cyminum plant, although the two look similar. Black cumin seeds are very dark, thin, and crescent shaped when whole. They are available for cooking use in many Middle Eastern and Indian supply stores, but seeds designated for cooking may not be as potent or as pure as seeds intended for medicinal use. In some regional cuisines, they are also used in cooking, as they add a unique nutty flavor to food and appear to have health benefits.

When ingested, black cumin seeds and extracts can be used for a number of conditions. They have been used for centuries to address digestive problems including stomach pain and flatulence. Black cumin seeds also have a long history in the natural treatment of asthma and other respiratory conditions. Compounds from the seeds appear to have antimicrobial properties, and are sometimes used to treat urinary tract infections. Oil from black cumin seeds can be used topically to treat dry skin, eczema, and other skin issues. In addition, black cumin seeds are sometimes used in beauty regimens to strengthen hair and nails, as well as making them more glossy.

In 1996, the United States Food and Drug Administration approved the use of a medicine incorporating an extract of black cumin seeds for immune system support. Several studies had shown that this extract could assist individuals with autoimmune disorders, and could possibly help to fight cancer as well. Naturopaths sometimes recommend regular doses of black cumin seeds to patients with weakened immune systems, as the whole seeds have been shown to boost the immune system. Pharmacological studies on compounds from the seeds show that they boost the production of bone marrow, natural interferon, and immune cells, helping to fight off diseases.