Black seed oil and asthma: what the evidence says

Four small randomized trials have tested black seed in people with asthma, always on top of their normal treatment: oil capsules (80 people, 4 weeks, double-blind), seed powder (76 people, 3 months, single-blind) and a boiled seed extract (29 people, 3 months). A 2020 meta-analysis that pooled four trials found better asthma-control scores and FEV1, but not peak flow.

The best-designed trial is also the most modest: on black seed oil the Asthma Control Test score was 21.1 against 19.6 on placebo after four weeks, blood eosinophils (allergy cells) fell, and lung function (FEV1) did not change significantly. A 2026 critical review called the clinical importance of that 1.5-point gain uncertain.

In a single-dose study in 15 people, a boiled seed extract opened the airways within 30 minutes, but less than the asthma drugs theophylline and salbutamol. Nothing here suggests black seed can replace an inhaler, and no trial lasted longer than three months.

This is close to a 4 on our scale: there is one positive double-blind trial, but it was small and short, a quarter of its participants dropped out, and its lung-function result was negative. Larger, longer trials have not been published; a children's respiratory-allergy trial registered in Indonesia in 2022 has no results, and a 90-child asthma trial from Tanta University (NCT07315555) is registered but not yet recruiting.

We screened all 14 human-study records PubMed returned for this search and read every abstract, plus a 2010 airway study the search classed as a lab paper. Five records were about other conditions or were surveys of herbal use; one, a 2003 case of asthma triggered by bird seed, was about a different plant also sold as 'black seed' (niger seed, Guizotia abyssinica).