Phosphatidylserine (PS) is a fat-soluble amino acid-derived compound that is abundant in the brain and contributes to cognitive function, which can improve memory and reduce cortisol in older adults.

Phosphatidylserine is a compound similar to dietary fat, and it is very common in human nervous tissue. It can be either synthesized or consumed through diet, but further benefits can be obtained through supplementation.

It is essential for cognitive function, but is not necessarily needed when the body is synthesizing. However, phosphatidylserine (PS) supplementation in older adults appears to improve memory and cognitive abilities.

A 2-month supplement of 200mg phosphatidylserine (PS) appears to improve ADHD (attention deficit and hyperactivity disorder in children) symptoms, secondary to improved ADHD symptoms, short-term auditory memory and impulsivity are also improved.

In otherwise healthy young adults given 400mg of PS for 2 weeks, processing speed (20%) and accuracy (13% increase in correct responses, 39% decrease in incorrect responses) improved significantly relative to placebo, and were independent of emotional state.

Phosphatidylserine appears to promote attention and reduce symptoms of ADHD, and it may be even more attention-seeking when the phosphatidylserine molecule contains fish oil fatty acids.

Phosphatidylserine supplements appear to have an anti-stress effect after long-term supplementation in healthy people without stress disorders.

Some studies point to long-term supplementation of phosphatidylserine during aging to reduce the rate of cognitive decline, or to show a tendency to reverse it in the range of 15-50mg/kg per day.

It has been noted that administering 200mg (intravenous) phospholipids to Alzheimer's patients is able to increase dopamine and serotonin metabolites, which are typically reduced in cognitive decline. Phosphatidylserine has been found to maintain 13.5-16% glucose metabolism during Alzheimer's disease after consuming 500mg of phosphatidylserine, which may be the mechanism for its observed benefits in some cases.

Ingestion of 300mg of phosphatidylserine from cow hide for 8 or 12 weeks, and the benefits of 400mg within 6 months have been noted to reach higher levels than pyridinol. A study using MMSE as a rating scale for older adults with age-related cognitive decline (but not diagnosed with Alzheimer's disease) also noted improvements in bovine corticophosphatidylserine at 300mg.

Parkinson's patients given bovine phosphatidylserine in other cognitive disease states have noted some improvement in EEG parameters, and for general dementia, 300mg bovine corticophosphatidylserine has noted some degree of benefit within 3 weeks of the 6-week trial, and improved memory and depressive symptoms in people with senile depression.

In people with age-related cognitive decline associated with pathology, there appears to be substantial evidence to support the role of bovine corticophosphatidylserine in symptom relief at 300mg daily. However, there is a lack of evidence to support the role of soy lecithinyl phosphatidylserine in this role, and there are suspicions that it may not be as effective.

PS supplements were associated with an increase in spatial memory of 50mg/kg (human equivalent is 8mg/kg) in older rats, and improvements in grooming and retention behavior were noted when injected at low concentrations (5-20 mg/kg) in older rats.

A study of 50mg/kg for 27 days in non-elderly rats (establishing a prointellectual effect rather than a cognitive rehabilitative effect) was able to significantly enhance brightness discrimination (indicating memory formation) without significantly affecting anxiety or depression symptoms.

In the cognitively impaired model, the memory promoting effect of phosphatidylserine supplementation also appeared in the old rat model and the young rats. The doses used in these rat studies were higher than usual (about 500mg for non-obese people), but not very high. The first report of cognitive improvement in older adults with aging-related mental disorders (non-pathological) was 300mg of soy-based phosphatidylserine (PS) at 3 months, in which Wechsler memory test scores improved and visual memory specifically improved; This was later replicated with 300mg of PS over 12 weeks, and two studies showed that supplementing with PS seemed to help with facial recognition in older adults at this dose.

In healthy older adults, it appears to benefit long-term supplementation of phosphatidylserine, which seems to be better suited to preventing dementia.

Therapeutic dose

The standard dose of phosphatidylserine (PS) is 100mg per dose, taken 3 times daily and 300mg per day. The dose appears to be effective as a daily preventative of cognitive decline, and 100mg daily may also provide some level of benefit (but less than 300mg).

Studies in children and adolescents to improve concentration tend to use 200mg, and have been successful with doses of 200-400mg in adults who are not older adults. Animal evidence also favors the use of doses associated with 550mg.