Phosphatidylserine
Phosphatidylserine is a vital component of neural cell membranes whose levels may decrease after age 50 and can cause a diminishment of mental function and memory. PS has been shown to improve concentration, learning and recall abilities in subjects with cognitive impairments due to Alzheimer's or aging. In healthy, non-active men, PS blunted the cortisol increase that usually accompanies stressful exercise. Elevated cortisol levels promote accumulation of visceral fat, and may interfere with adaptation to athletic training.

Dosage: 100 mg to 800mg daily.
Precautions: Consult you physician before taking Phosphatidylserine if pregnant. May interact negatively with anticoagulants. The only other reported side-effect is occasional, mild nausea.