Quick Comparison
| Black Seed Oil | Citicoline (CDP-Choline) | |
|---|---|---|
| Half-Life | 6-8 hours (thymoquinone) | 56-71 hours (sustained release characteristics) |
| Typical Dosage | Standard: 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: 250-500 mg daily. Clinical studies use 500-2000 mg daily. Take in the morning — mildly stimulating. Cognizin is the most studied form. Can be split into 2 doses. Often combined with racetams to provide the choline needed for enhanced acetylcholine turnover. |
| Administration | Oral (oil, softgels, capsules). Cold-pressed oil preferred. Take with food. | Oral (capsules, powder). Cognizin branded form is most studied. Take in the morning. |
| Research Papers | 9 papers | 10 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.
Citicoline (CDP-Choline)
Citicoline (CDP-choline) is hydrolyzed in the gut by alkaline phosphatase to choline and cytidine-5'-monophosphate, which are absorbed separately and reassembled in the brain via the Kennedy pathway. Choline feeds two critical pathways: (1) Acetylcholine synthesis via choline acetyltransferase (ChAT) — the primary memory and learning neurotransmitter acting at muscarinic and nicotinic receptors. (2) Phosphatidylcholine synthesis via CTP:phosphocholine cytidylyltransferase — the structural component of neuronal membranes and synaptic vesicles. Cytidine is dephosphorylated to uridine, converted to UTP, and supports RNA synthesis and CDP-choline formation for synapse formation. Citicoline also activates SIRT1 (possibly via NAD+ modulation) and increases brain norepinephrine and dopamine (mechanism unclear — may enhance synthesis or release). It is the only choline source providing both cholinergic and membrane-building support in one molecule.
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.
Citicoline (CDP-Choline)
Common
Headache (especially with racetams — indicates too much cholinergic stimulation), nausea, diarrhea.
Serious
None documented at standard doses.
Rare
Insomnia, blurred vision.
Full Profiles
Black Seed Oil →
Extracted from Nigella sativa seeds, black seed oil contains thymoquinone — a compound with potent anti-inflammatory, antioxidant, and neuroprotective properties. Used in traditional Middle Eastern medicine for over 2,000 years, modern research supports cognitive benefits through anti-neuroinflammation, acetylcholinesterase inhibition, and GABA modulation. Also supports metabolic health and immune function.
Citicoline (CDP-Choline) →
A naturally occurring intermediate in the synthesis of phosphatidylcholine, the primary phospholipid in neuronal cell membranes. Citicoline provides both choline (for acetylcholine and phospholipid synthesis) and cytidine (converted to uridine, supporting RNA and synapse formation). It is prescribed in Europe and Japan for stroke recovery and cognitive decline. Cognizin is the most studied branded form.