Phosphatidylserine
A fat found in every cell membrane, best known as a memory supplement.
- Memory
- Attention and focus
- Stress
- Exercise and recovery
A plain-English overview, not advice. Written from published reviews and trials and from what people say in public forums.
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On this page
What is phosphatidylserine?
Phosphatidylserine is a phospholipid: one of the fats that make up the membrane around every cell, and nerve tissue carries more of it than anywhere else. The body makes its own, taking a related phospholipid and swapping its head group for the amino acid serine. What is sold is made from a plant source, and British labels name soy or sunflower; the older supplements were made from cow brain instead. Reviewers describe it as sold above all as a brain supplement, with labels usually carrying somewhere between 100 and 500 mg a day.
Why do people take phosphatidylserine?
Memory
The thinking. Memory is what most people come to phosphatidylserine for: names that go missing, a thread of thought that slips. The thinking is about the cell membrane, which reviewers describe as richest in this phospholipid in nerve tissue, where it takes part in the signalling those cells run on. The idea is that a capsule adds to what the body makes.
What research has found. One trial here measured memory directly: healthy children aged eight to twelve took 100 mg a day of sunflower-derived phosphatidylserine as a gummy for twelve weeks, and nothing separated from the placebo on memory, mood or sleep. Among the children who had started below the group’s middle, one test of remembering where things were did separate. Reviewers say the older adult work, mostly in people whose thinking had declined, leaves the picture unclear. Few studies have measured this yet, so there is little to go on either way.
Attention and focus
The thinking. The other half of the brain reputation is attention: parents buy it for a child who cannot stay with a task, adults for the same in themselves. The thinking turns towards the messengers, reviewers describing phosphatidylserine as taking part in how nerve cells release acetylcholine, dopamine and noradrenaline.
What research has found. Most of this research is in children with an ADHD diagnosis, at 200 to 300 mg a day for two or three months. A pooling of three trials, 216 children, found a modest average gain in inattention scores, while scores for overall symptoms and for hyperactivity did not separate from the placebo. A review of eleven trials of phosphatidylserine-containing supplements found three reporting gains in attention and impulsivity, and two finding none. Studies here point in different directions, so this one is still being worked out; the dose, how long people took it and who took part all seem to matter.
Stress
The thinking. Phosphatidylserine also has a following among people who feel permanently wound up. The thinking is the hormone side of stress: reviewers describe it as involved in the body’s neuroendocrine responses, and early work in exercising people asked whether it changed the rise in cortisol that follows hard training.
What research has found. The one trial here took a different measure. Sixteen healthy volunteers sat cognitive tasks under pressure, then took phosphatidylserine or a placebo for six weeks and sat them again. The electrical activity recorded over the right front of the head shifted towards the pattern the researchers link with being more relaxed. Very little research has measured this so far, either way.
Exercise and recovery
The thinking. People who train hard are the other group that buys it, usually thinking of recovery: the ache two days after a heavy session, the flatness of a long training block. The thinking rests on the same stress-hormone idea, together with the part reviewers give phosphatidylserine in how tissue answers inflammation, and as an antioxidant.
What research has found. Both trials here gave active men 750 mg a day of soy-derived phosphatidylserine. In one, fourteen men cycled to exhaustion and lasted about two minutes longer after ten days on it, where the placebo group did not change; cortisol and how they rated the effort were no different. In the other, eight men ran downhill to bring on next-day soreness, and neither that nor the blood markers of muscle damage differed from the placebo. The studies disagree, so this is unsettled: dose, duration and who took part all seem to shift the result.
What does phosphatidylserine do in the body?
Phosphatidylserine is not a nutrient you can run short of in the way a vitamin is. It is building material: one of the fats that make the membrane around every cell, sitting on the inner face of it, and packed most densely into nerve tissue. The body makes its own, taking a related phospholipid and swapping its head group for the amino acid serine.
Membranes are not only walls. Reviewers describe phosphatidylserine as the surface several signalling enzymes must touch before they work, and as taking part in the release of the chemicals nerve cells send one another. It pairs with the omega-3 fat DHA, which the brain is rich in and which drives the body to make more phosphatidylserine. When a cell dies, its phosphatidylserine turns to the outside of the membrane as the flag that has it cleared away, and it is the surface on which blood clotting begins. Swallowed as a supplement, reviewers judge it likely adds a small but measurable amount to cell membranes.
What do people say about taking phosphatidylserine?
These are anecdotes people have shared, not evidence.
What people like
- Three of the five discussions read come from one chronic-illness forum, so the sleep and cortisol reports there may reflect that group.
- Feeling mentally sharper is the commonest good report: clearer thinking, easier focus, quicker recall, sometimes within a week and sometimes after a month.
- Several who take it at bedtime describe deeper sleep and fewer wakings, one noticing only after stopping and waking wired again.
- A handful have taken it for years and stay with it; one says the sharpness fades within days of missing a dose.
- Some describe feeling calmer through a stressful patch, though several of those were taking it inside a multi-ingredient blend rather than on its own.
Common complaints
- Noticing nothing at all is a common report, including from people who kept at it for months or more than a year.
- Feeling groggy, spaced out or heavy the next day comes up repeatedly, and is the usual reason people give for stopping.
- Several report the opposite of what they hoped for at night: worse sleep, a wired feeling or an unsettled mood, and they stopped.
- Getting the amount right takes trial and error, people moving between doses and times of day for weeks before settling or giving up.
How people take it
- The amounts named run from 100 mg to 600 mg a day, with 100 mg and the 400 to 500 mg range coming up most.
- Timing is what people experiment with most: at night for sleep, in the morning for clear thinking, and several swap between the two.
- It is often taken alongside other things, fish oil and calming supplements among them, which makes any single effect hard to separate.
- People give it weeks rather than days, a month being the shortest trial described and several months the more usual plan.
Read from these public discussions:
- Phosphatidylserine brand and dosage help needed (Phoenix Rising ME/CFS Forums, 2012)
- The Awesome Foursome + Phosphatidyl serine (Phoenix Rising ME/CFS Forums, 2012)
- Insomnia Rant Part Two/Phosphatidylserine (Phoenix Rising ME/CFS Forums, 2012)
- Has anyone taken phosphatidylserine (for cortisol reduction / better sleep)? (TrainerRoad, 2020)
- Phosphatidylserine reviews and ratings (WebMD user reviews)
What forms of phosphatidylserine are there?
| Form | What’s different | Per serving, on products we list |
|---|---|---|
| Phosphatidylserine | The same phospholipid whatever the source; labels name soy or sunflower, and older supplements used cow brain. | 40 mg |
What else is worth knowing about phosphatidylserine?
- Trials used 100 mg to 750 mg a day, the sports ones at the top of that range. Reviewers say supplements on sale usually carry 100 to 500 mg a day. Labels give the amount per serving, and a serving may be more than one capsule.
- Some labels print the weight of the whole blend rather than the phosphatidylserine in it, so a 500 mg complex providing 100 mg phosphatidylserine counts as 100 mg when prices are compared here.
- Cow brain was the original starting material and soy the one that replaced it. Reviewers prefer a plant source for people, because of the chance of passing on infection carried in brain tissue.
- The trials were small and in particular groups: children aged four to fourteen, with and without an ADHD diagnosis, and young active men in the exercise trials. They reported it as well tolerated with no adverse effects, and reviews of the clinical studies say the same.
If you take medication, are pregnant, or have a health condition, check with a pharmacist or GP first.
The research behind this page (12 studies)
- The cognitive effects of supplementation with sunflower phosphatidyl serine in healthy children aged 8 to 12 years: a randomized controlled trial. (2025, randomised trial)
- The Impact of Citicoline/Phosphatidylserine Supplementation on Cognitive Performance and Executive Functions in Mental Disorders: A Systematic Review of Controlled Trials. (2026, systematic review)
- Phosphatidylserine for the Treatment of Pediatric Attention-Deficit/Hyperactivity Disorder: A Systematic Review and Meta-Analysis. (2021, meta-analysis)
- The effect of phosphatidylserine administration on memory and symptoms of attention-deficit hyperactivity disorder: a randomised, double-blind, placebo-controlled clinical trial. (2014, randomised trial)
- Influence of phosphatidylserine on cognitive performance and cortical activity after induced stress. (2008, randomised trial)
- Effects of phosphatidylserine on exercise capacity during cycling in active males. (2006, randomised trial)
- Phosphatidylserine supplementation and recovery following downhill running. (2006, randomised trial)
- Phosphatidylserine in the brain: metabolism and function. (2014, review)
- Phosphatidylserine, inflammation, and central nervous system diseases. (2022, review)
- Phosphatidylserine: A comprehensive overview of synthesis, metabolism, and nutrition. (2024, review)
- Phosphatidylserine in Diabetes Research. (2023, review)
- Effects of phosphatidylserine supplementation on exercising humans. (2006, review)
How much does phosphatidylserine cost?
That depends on the form and the pack, so we work out the price of the same dose of every phosphatidylserine product we can find and rank them.