Phosphatidylserine
Phosphatidylserine (PS)
Supplements. Modern nutrition.
Also called PS, Soy phosphatidylserine, Sunflower phosphatidylserine
Pinyin: lín zhī xiān sī ān suān
Spanish: Fosfatidilserina
Not studied in pregnancyA fat found in the membranes of brain and nerve cells, sold as a supplement mainly to support memory as people age.
Did you know? When a cell is about to die, it flips phosphatidylserine to its outer surface, which tells cleanup cells to remove it.
What it may help, and how strong the proof is
- Memory & focus. A 2022 meta-analysis pooled nine studies (five randomized trials and four uncontrolled before-and-after studies, about 960 people). It found a modest memory benefit in older adults with cognitive decline. Effects were small, most trials were short, and product sources varied.See the research: 31 studies in peoplePromising proof
- Memory & focus. The claim that it prevents dementia is not proven.See the research: 31 studies in peopleUnproven
Parts of the body
Traditional use
Not part of an old herbal system. Early supplements came from cow brain, a source that was dropped because of mad cow disease concerns. Most products now use soy or sunflower.
How it is classified
- Herbal actions
- Brain tonic, Nutritive. Energy: neutral.
How people take it
Studies used about 100 to 300 milligrams a day, most often 300 milligrams, for 6 weeks to 6 months. Higher doses and longer use have not been well studied.
Capsule and powder.
Where to get it
Most products are made from soy or sunflower lecithin, which contains a small share of PS. Small amounts occur in foods such as soy, egg yolk and organ meats. It is sold as softgels, capsules and powders at pharmacies, health stores and online.
Be careful
Short trials report good tolerance. Possible side effects include upset stomach, and some people report trouble sleeping if they take it late in the day. Interactions with cholinergic and anticholinergic drugs have not been well studied. Pregnancy, breastfeeding and long-term safety are not well studied, so avoid it during pregnancy and nursing unless a clinician approves.
Avoid if: pregnancy; breastfeeding.
Mixing with other things
- Works well together
Both are sold for brain health. Few trials have tested them together.
The honest take
Phosphatidylserine has been studied for memory in older adults, and the effect so far is small. Trials are short and mostly small. It is not proven to prevent dementia, and claims that it prevents or slows Alzheimer's disease are not proven either.
Sources
Each “See the research” link opens PubMed, the U.S. National Library of Medicine's index of medical studies, showing only trials and reviews done in people. The number tells you how much a use has been tested, not whether it worked. The proof rating tells you that.
Study counts checked October 2026.