Quick Comparison
| Ginkgo Biloba | Phosphatidylserine | |
|---|---|---|
| Half-Life | 3-10 hours (varies by constituent) | Not well-characterized orally; brain PS turns over slowly |
| Typical Dosage | 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. | Standard: 100-300 mg daily in 1-3 doses. Most studies use 300 mg daily. Soy-derived and sunflower-derived forms are both effective. Take with food for absorption. |
| Administration | Oral (capsules, tablets, liquid extract). Standardized extract recommended over raw leaves. | Oral (softgels, capsules). Soy-derived or sunflower-derived. Take with fat for absorption. |
| Research Papers | 9 papers | 10 papers |
| Categories |
Mechanism of Action
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.
Phosphatidylserine
PS is a structural component of neuronal membranes, maintaining membrane fluidity and supporting receptor function, ion channel activity, and neurotransmitter release. It localizes preferentially to the inner leaflet of the plasma membrane via flippase enzymes (P4-ATPases), where it serves as a cofactor for protein kinase C (PKC) isoforms alpha, beta, and gamma — PKC activation phosphorylates substrates including MARCKS and GAP-43, critical for synaptic plasticity and memory consolidation. PS modulates the HPA axis via glucocorticoid receptor feedback, reducing cortisol by 15-30% in stressed individuals. It facilitates choline transport via high-affinity choline transporter (CHT1) into presynaptic terminals, supporting acetylcholine synthesis by choline acetyltransferase. PS also regulates NMDA receptor function and supports Na+/K+-ATPase activity. Downstream, PS enhances CREB phosphorylation and BDNF expression in hippocampal neurons.
Risks & Safety
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.
Phosphatidylserine
Common
Mild gastrointestinal discomfort, insomnia at high doses.
Serious
May interact with blood thinners.
Rare
Allergic reaction in soy-sensitive individuals (use sunflower-derived).
Full Profiles
Ginkgo Biloba →
One of the oldest living tree species on Earth, used in traditional Chinese medicine for millennia. Ginkgo extract (EGb 761) is one of the most prescribed herbal medicines in Europe for cognitive decline and cerebrovascular insufficiency. It improves cerebral blood flow, has antioxidant properties, and modulates neurotransmitter systems. Most effective in older adults with declining cognitive function.
Phosphatidylserine →
A phospholipid that constitutes 15% of the brain's total phospholipid pool and is concentrated in neuronal cell membranes. Phosphatidylserine (PS) supports memory, cognitive function, and cortisol regulation. It is the only nootropic with an FDA-qualified health claim: 'consumption may reduce the risk of cognitive dysfunction in the elderly.' Particularly effective for age-related cognitive decline.