Black seed

Updated October 2026 · 8 min read

In classical medicine

Black seed (الحبة السوداء, also called habbat al-barakah, black cumin or kalonji) is the small black seed of the Nigella sativa plant. It is one of the most widely used remedies in traditional Islamic medicine.

Ibn Sina, in the Canon of Medicine, is often quoted as describing black seed (shuniz) as stimulating the body's energy and helping it recover from tiredness and low spirits. Classical physicians also used it for coughs, intestinal wind and parasites, and as an oil for the skin. Their praise was broad, but black seed does not replace medical treatment.

Traditional uses

• coughs, colds and congestion
• indigestion and bloating
• skin complaints, used as an oil
• general strength and resistance to illness

It is usually taken as ground seed with honey, or as cold-pressed oil, and sprinkled on bread and pastries.

What the research shows

Black seed is one of the more studied traditional remedies. Its main active compound, thymoquinone, shows anti-inflammatory and antioxidant effects in the lab. Human trials are where we need to be careful. They are mostly small, short (about 8 to 12 weeks) and use very different products: seed powder, oil or capsules. Reviews of these trials suggest:

• Blood sugar: modest reductions in fasting glucose and HbA1c in people with type 2 diabetes.
• Blood pressure and cholesterol: small reductions in blood pressure, LDL and triglycerides.
• Asthma and allergic rhinitis: some trials show fewer or milder symptoms.
• Weight: a small decrease in weight and waist size, mostly alongside diet changes.

Exciting lab results on cancer, infections and immunity come from cells and animals. They have not been shown to work in people, so be wary of any product that promises them.

How to use it

• Seeds: about half to one teaspoon of ground seeds a day, mixed into honey, yogurt or food. Most trials used 1 to 3 grams a day.
• Oil: half to one teaspoon a day, cold-pressed. Test a drop on your skin before using it as a topical oil, since some people get a rash.
• Buy small amounts of whole seeds and grind them fresh. Store in a dark, cool, airtight jar.
• Give any trial at least 8 weeks and track a real measure, such as home blood pressure or HbA1c, rather than how you feel.

Who should be careful

• Pregnancy: avoid medicinal amounts. Small amounts used in cooking are fine.
• Diabetes or blood pressure medication: black seed can add to their effect, so monitor closely and tell your doctor.
• Blood thinners or a bleeding disorder, and surgery in the next 2 weeks: it may affect clotting.
• Transplants and immunosuppressants: ask your specialist first.
• Stop if you get a rash, stomach upset or any allergic reaction.