Phosphatidylserine (PS) is essential for healthy brain cell membranes and to maintain an environment required for optimal brain function. Phosphatidylserine improves cell-to-cell communication in the brain, and thus cognitive function, at least in part by increasing cell membrane fluidity. Other mechanisms of action include enhancing cell metabolism (such as glucose utilization) and neurotransmitter formation. Phosphatidylserine also appears to have antioxidant activity, which would protect brain cells from free radicals. Abundant clinical research has shown this nutrient is important in promoting optimal cognitive function, particularly in the aging brain.

Studies show supplementing with phosphatidylserine can lower cortisol spikes in response to stress. PS modulates cortisol by blunting the release of the hormone in the brain (ACTH) that normally signals the adrenal glands to secrete cortisol.