Black Seed
Nigella sativa
B Limited clinical evidenceA spice seed for which small studies saw modest falls in blood sugar, cholesterol and blood pressure. Kitchen amounts are safe.
Image: Herbadex Botanik Stüdyosu · Özel Üretim
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At a glance
Black seed (Nigella sativa) is a black-seeded spice used on bread and cheese. Thymoquinone is thought to be mainly responsible for its effects. Meta-analyses of small trials show modest falls in fasting blood sugar in type 2 diabetes, cholesterol and blood pressure; study quality is limited. The saying "a cure for everything but death" is not a scientific claim.
Updated: October 15, 2026
ℹ Compiled from standard pharmacognosy references and clinical literature summaries where no formal EMA monograph exists.
What is it used for?
B Limited clinical evidence
Limited clinical evidence: Supported by small-scale human clinical studies, though sample size and study quality are limited.
How do we rate evidence levels? →Small studies suggest it may help modestly lower fasting blood sugar in type 2 diabetes. [1]
B Limited clinical evidence
Limited clinical evidence: Supported by small-scale human clinical studies, though sample size and study quality are limited.
How do we rate evidence levels? →Small studies reported modest falls in total and LDL cholesterol and blood pressure. [1]
C Laboratory / animal evidence
Laboratory / animal evidence: Based only on laboratory (in vitro) or animal studies; not clinically proven in humans.
How do we rate evidence levels? →Lab studies showed anti-inflammatory and bronchodilating effects. [1]
How is it used?
Food
Sprinkle seeds on bread, cheese, salads and yoghurt, or grind and mix with honey. Studies used 1–3 g of ground seed daily.
Amount: 1–3 g daily
Duration limit: 8–12 weeks (in studies)
[1]Safety & interactions
- Amounts used as a spice in food are generally safe; this does not apply to concentrated extracts and supplements.
- People on diabetes or blood pressure medicines should monitor blood sugar and blood pressure.
- Stop high-dose use 2 weeks before surgery (theoretical effect on clotting).
- Avoid high doses (supplements) in pregnancy; amounts in food are fine.
Drug interactions
| Medicine / substance | Effect | Severity |
|---|---|---|
| Diabetes medicines | May further lower blood sugar. [2] | Moderate |
| Blood pressure medicines | May further lower blood pressure. [2] | Minor |
| Anticoagulants | High doses could theoretically raise bleeding risk. [2] | Minor |
Side effects
- Indigestion, bloating
- Rarely allergic rash
⚕ When to see a doctor
- If high fever, shortness of breath or purulent/bloody phlegm develops
- If symptoms do not improve within 1–2 weeks or worsen
- If severe abdominal pain, jaundice, rash or allergic reaction occurs
Did you know?
Black seeds were found in the tomb of Tutankhamun. [1]
Frequently asked questions
Is black seed a cure for everything?
No. That traditional saying is not a scientific claim; evidence points to limited benefit in a few areas.
Does black seed lower blood sugar?
Small studies saw a modest fall; it does not replace diabetes treatment.
How is black seed eaten?
Sprinkled on bread, cheese and salads, or ground and mixed with honey.
Sources
- WHO Monographs on Selected Medicinal Plants (Volumes 1–4)World Health Organization · 2009
- Herbs at a Glance: Evidence-Based Fact Sheets on Botanical ProductsNIH NCCIH · 2024
Cite This Page
Black Seed (Nigella sativa). Herbadex — Doğal Şifa Rehberi (2026). https://herbadex.com/en/herb/black-seed/
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