Phosphatidylserine

Phosphatidylserine is a type of molecule known as a phospholipid. Phospholipids are a group of molecules that are chemically similar in structure to fats that make up the membrane of all cells. Phosphatidylserine, in particular, is abundant in the cells of the nervous system, accounting for 13–15% of all phospholipids in the cerebral cortex (the part of the brain that is responsible for thinking). Phosphatidylserine usually stays on the inside of the cell membrane, where it plays an important role in cell signaling. It does this by controlling the substances that move in and out of the cell and modulating the release of neurotransmitters, which is how brain cells communicate with one another (6).

Phosphatidylserine can be produced naturally in the body but it can also come from food. Foods containing phosphatidylserine include organ meats, like liver and kidney, and soybeans. Phosphatidylserine used to be primarily sourced from bovine brains, but given the growing concern surrounding mad cow disease, it is now typically sourced from soy.

Because phosphatidylserine plays an important role in brain cell function, it is thought that supplementation with phosphatidylserine can protect brain cells and promote cognition. One review that looked at over 127 studies found that supplementation with phosphatidylserine could have widespread effects in the brain including slowing or reversing nerve cell deterioration, supporting memory, and helping with concentration, problem-solving, language skills, and communication (2).

Phosphatidylserine also has the following health benefits:

Although the evidence is limited, phosphatidylserine has been shown to improve factors associated with stress in a few areas:

• Mood: In one study, young adults were given a stressful mental arithmetic task. The ones who had been supplementing with 300 mg per day of phosphatidylserine for one month reported less stress and an overall better mood (1).

• Cortisol levels: Cortisol is often considered the “stress hormone.” In one small study, levels of cortisol and ACTH (the hormone that stimulates cortisol release) were measured after a mental and emotional stressor was present. In patients who had been taking 400 mg per day of phosphatidylserine for three weeks, cortisol and ACTH levels were blunted and participants reported decreased distress. Interestingly, these effects were not seen at doses of 600 mg per day and 800 mg per day (3).

• Exercise-induced stress: One study looked at the effects of supplementation with 200 mg per day of phosphatidylserine for 42 days specifically in golfers. The study did not find a statistically significant improvement in perceived stress levels but did find a statistically significant improvement in “good ball flights” (4). Another small study on soccer players found that supplementation with phosphatidylserine did not reduce cortisol or improve markers of muscle damage but it did increase the time to exhaustion while running. In this study, participants took 750 mg per day for ten days (7).

Nutritional supplements, like phosphatidylserine, are not reviewed by the FDA for safety and effectiveness. The effective daily dose can therefore only be estimated based on what has been tested in studies. Dosages used in studies examining phosphatidylserine’s effects on stress levels range from 60–800 mg per day. However, supplements derived from marine sources sometimes include docosahexaenoic acid (DHA), which may influence the efficacy of the phosphatidylserine (6). Additionally, studies have found that higher doses of phosphatidylserine are not necessarily associated with the same benefits as lower doses (3). This makes determining the most effective dose of phosphatidylserine difficult.

Phosphatidylserine can be found in food or in nutritional supplements.

Phosphatidylserine has not been found to have significant side effects and was determined to be safe for supplementation in older persons at doses up to 200 mg three times per day (5). Because of concern surrounding mad cow disease, phosphatidylserine is no longer sourced from bovine brains. However, no actual cases of disease transmission due to phosphatidylserine supplementation have been reported.