A fat that builds cell membranes and concentrates in brain tissue. Two effects have real human data: lowered stress-hormone surge after a stressful event, and possible memory help in older adults already declining. The first is better established; the second contested. Harms are modest and mostly digestive. Almost every trial was funded by a seller. Standing remains unresolved. (Full Review)
| Marker | Target | Why |
|---|---|---|
| Morning serum cortisol | 10–15 µg/dL | Confirms the stress axis is being dampened, not flattened |
| Four-point salivary cortisol curve | Waking rise of 50–75% at 30 minutes, falling below 0.10 µg/dL by bedtime | Shows the shape of the daily rhythm, which a single draw cannot |
| DHEA-S | Men 250–450 µg/dL; women 150–350 µg/dL | Pairs with cortisol to show whether adrenal output is balanced or skewed |
| Cortisol-to-DHEA-S ratio | Track change from the individual's own baseline; no established target | Single best summary of stress-axis balance over time |
| Standardised cognitive composite score | No established target; track change from the individual's own baseline | The primary outcome for cognitive use, and the only honest way to judge response |
| Resting blood pressure | Below 120/80 mmHg | Long-term marine phosphatidylserine use reduced resting diastolic pressure in one trial |
| Platelet count | 175–350 × 10⁹/L | Baseline for anyone combining with anticoagulant or antiplatelet therapy |
| Omega-3 Index | 8–12% | Relevant only for marine-sourced products, which contribute docosahexaenoic acid |
| Body weight | Track change from the individual's own baseline; no established target | A slight gain was recorded over 30 weeks of marine phosphatidylserine |
Cadence: Baseline before starting, with the cognitive battery run twice; salivary cortisol curve repeated at 4 weeks for stress use and the primary measure at 12 weeks; thereafter every 6–12 months for as long as supplementation continues.