Also known as: Nigella sativa, Black cumin, Kalonji, Thymoquinone, Habbatus sauda
BotanicalGood evidence
Oil pressed from Nigella sativa seeds, standardised to thymoquinone. A long traditional history and a growing modern trial record, most of it on metabolic and inflammatory markers.
Typical dose
500.0–2000.0 mg per day
With food, split across the day
What it is
Nigella sativa is a flowering plant native to South and Southwest Asia, whose small black seeds have been used across the Middle East, North Africa and South Asia for centuries, both as a spice and in traditional medicine.
It is often called black cumin, which is misleading since it is unrelated to cumin. Kalonji is the common name in South Asian cooking, where the seeds are used whole.
The compound of interest is thymoquinone, and quality products are standardised to it, typically 0.5 to 5 per cent. That range is wide enough to matter considerably: a product at 0.5 per cent and one at 3 per cent are not comparable at the same millilitre dose. Thymoquinone degrades with light and heat, so cold-pressed oil in dark glass is the sensible form.
How it works
Thymoquinone has documented antioxidant activity and effects on inflammatory signalling pathways, including NF-kB, which is the mechanism most often credited for its broad range of reported effects.
Research has also reported effects on how effectively cells respond to insulin, and on lipid handling, which underpins the metabolic findings.
Additional work covers immune modulation and effects on airway smooth muscle. As with many traditional preparations, the mechanistic literature is broad rather than deep, and human confirmation trails well behind the laboratory work.
What the evidence shows
The human trial record is larger than for most emerging botanicals, though the trials themselves are generally small and concentrated in a limited number of research settings.
Metabolic markers are the best-studied area. Meta-analyses have reported reductions in fasting glucose and improvements in lipid measures, with reasonably consistent direction across trials.
There is also a body of work on blood pressure with modest favourable findings, and a smaller literature on body weight. Trial quality is variable and independent replication outside the originating regions is limited, so treat this as promising rather than established.
Dosing
Common intake is 500-2,000 mg of oil daily, or roughly one to two teaspoons, split across servings. Trials have used a wide range, and doses of ground seed are considerably higher than oil doses.
Dose against thymoquinone content where it is declared. Given the range between products, a bottle that does not state it gives you no basis for comparison.
Take with food, since it is an oil and absorbs better alongside a meal. The taste is strong, bitter and peppery, and many people prefer capsules for that reason alone. Store in dark glass away from heat, since thymoquinone degrades with light and warmth.
At a glance
Common forms
Cold-pressed oil, Thymoquinone-standardised oil, Softgel capsules, Whole or ground seed
Half-life / duration
Effects on metabolic markers accrue over 8-12 weeks
Timing
With food, split across the day
Competition status
Permitted — not on the WADA Prohibited List
Category
Botanical
Safety and side effects
Generally well tolerated, with a long history of dietary use. Digestive upset, nausea and reflux are the most commonly reported effects, usually reduced by taking it with food.
Skin reactions have been reported with topical use, which is a separate application from taking it internally.
Because it may lower blood sugar and blood pressure and has a mild effect on how readily blood clots, take care if any of those are being managed. Speak to your doctor before use if you take regular medication, and stop before scheduled surgery.
Who should avoid it
Take care if your blood sugar or blood pressure is being managed, or if you take anything affecting blood clotting. Speak to your doctor before use if you take regular medication. Stop before scheduled surgery. Avoid at supplemental doses in pregnancy and breastfeeding.
This entry is provided for information only. Food supplements should not be used as a substitute for a varied and balanced diet and a healthy lifestyle. Consult a qualified healthcare professional before use if you are pregnant, breastfeeding, taking medication or under medical supervision.
