Quick Comparison

Black Seed OilGinkgo Biloba
Half-Life6-8 hours (thymoquinone)3-10 hours (varies by constituent)
Typical DosageStandard: 1-3 teaspoons oil daily, or 500-1000 mg standardized extract (minimum 2% thymoquinone). Take with food. Cold-pressed oil retains more bioactives. Taste is peppery/bitter — capsules available for those who dislike the taste.Standard: 120-240 mg daily of standardized extract (24% flavone glycosides, 6% terpene lactones). EGb 761 is the most studied form. Often taken in 2-3 divided doses.
AdministrationOral (oil, softgels, capsules). Cold-pressed oil preferred. Take with food.Oral (capsules, tablets, liquid extract). Standardized extract recommended over raw leaves.
Research Papers9 papers9 papers
Categories

Mechanism of Action

Black Seed Oil

Thymoquinone is the primary bioactive, providing neuroprotection through multiple mechanisms: it scavenges reactive oxygen species (superoxide, hydroxyl radical, peroxynitrite) and upregulates Nrf2/ARE pathway, increasing glutathione (via GCLC, GSS), superoxide dismutase (SOD1/SOD2), and catalase. It inhibits NF-kB by preventing IkB-alpha degradation and blocking p65 nuclear translocation, reducing neuroinflammation and pro-inflammatory cytokine release. Thymoquinone inhibits acetylcholinesterase (AChE) at the peripheral anionic site, increasing synaptic acetylcholine. It modulates GABA-A receptors (positive allosteric modulation at benzodiazepine site), providing anxiolytic effects. Thymoquinone protects neurons from amyloid-beta toxicity by reducing oxidative stress and inhibiting beta-secretase (BACE1). It reduces tau hyperphosphorylation by inhibiting GSK-3beta and CDK5.

Ginkgo Biloba

Ginkgo biloba extract (EGb 761) contains flavonoids (quercetin, kaempferol, isorhamnetin) and terpenoids (ginkgolides A, B, C, J and bilobalide). The flavonoids are potent antioxidants that scavenge superoxide, hydroxyl radicals, and peroxynitrite, and protect neurons from oxidative damage; they may also chelate iron. The terpenoids (ginkgolides and bilobalide) improve blood flow by antagonizing platelet-activating factor (PAF) at the PAF receptor, which reduces platelet aggregation, blood viscosity, and improves microcirculation in the brain. Bilobalide protects mitochondria and reduces apoptosis. Ginkgo modulates nitric oxide (NO) availability via endothelial nitric oxide synthase (eNOS) for vasodilation. It inhibits monoamine oxidase A and B (MAO-A, MAO-B), mildly elevating dopamine and serotonin. It may enhance cholinergic transmission and reduce amyloid aggregation.

Risks & Safety

Black Seed Oil

Common

Mild gastrointestinal discomfort, burping.

Serious

May lower blood pressure and blood sugar — caution with relevant medications. May slow blood clotting.

Rare

Allergic reaction, contact dermatitis with topical use.

Ginkgo Biloba

Common

Headache, dizziness, gastrointestinal discomfort, allergic skin reactions.

Serious

Increased bleeding risk — do not combine with blood thinners (warfarin, aspirin) or take before surgery.

Rare

Seizures (particularly with raw seeds, not standardized extract), severe allergic reactions.

Full Profiles