Phosphatidylserine: Benefits, Dosage, and Side Effects

There are very few supplements that are ever approved to make health claims by the FDA. The one we are going to discuss today was granted two. This supplement has been researched in more than 40 human clinical trials over a period of more than 30 years in research studies throughout the world. More than 20 placebo-controlled clinical trials have consistently proven that it has considerable value as a dietary supplement and that the normal diet provides an insufficient amount of it.

This supplement is phosphatidylserine (PS). In this article, we will discuss what phosphatidylserine is, what it is used for, the benefits of supplementation, when you should take it, and if there are any side effects.

What Is Phosphatidylserine?

Phosphatidylserine (PS) is an amino acid derived agent that is a major phospholipid (fat soluble) of all cell membranes. It is very similar to fat and can be made by the body and consumed through what we eat. Further benefits can be obtained through phosphatidylserine supplementation.

In humans, the majority of phosphatidylserine is found in the brain (15%), lungs (7.4%), testes (6.4%), kidneys (5.7%), liver (3.8%), skeletal muscle (3.3%), heart (3.2%), and blood plasma (0.2%). The total phosphatidylserine pool in the body is ~60 grams, with 30 grams in the brain and 30 grams in the rest of the body.

How Is Phosphatidylserine Made?

Phosphatidylserine is synthesized in bacteria by condensing serine, an amino acid, with cytidine diphosphate-activated PA. In humans, PS is made by exchange reactions with the compounds phosphatidylcholine and phosphatidylethanolamine.

Alternatively, PS can also generate phosphatidylethanolamine and phosphatidylcholine, but this can only happen in the liver.

What Are Natural Source Of Phosphatidylserine?

The majority of dietary phosphatidylserine can be found in:

  • Meat
  • Fish
  • Krill Oil
  • Soy Lecithin

However, PS is most abundant in the brains and innards (liver and kidneys) of the animals humans consume. Phosphatidylserine is also found in dairy products and vegetables, but in very small amounts excluding white beans.

On average, humans consume 130 mg of phosphatidylserine daily from the food sources listed above. However, the real benefits of PS come in to play when 200-300 mg is taken through supplementation.

What Is Phosphatidylserine Used For? What Does Phosphatidylserine Do?

Phosphatidylserine in mainly used to prevent cognitive decline in the elderly and to improve attention in children or adolescents. But there is an emerging body of evidence that suggests phosphatidylserine can do so much more in both general and athletic populations.

Phosphatidylserine Benefits

The benefits of PS for the general population are:

  • Improves brain functions as we age. In fact, Phosphatidylserine is THE ONLY supplement carrying an FDA approved health claim for improving brain functions.
  • Improves symptoms of ADHD and mental stress in young people.
  • Decreases cortisol.
  • Improves sleep quality.
  • Reduces fatigue.
  • Decreases stress.
  • Increases brain processing speed and accuracy.

The benefits of PS for athletic populations are:

  • Improved mood.
  • Enhanced cognitive functioning.
  • Lowers physical and psychological stress.
  • Increased anaerobic running capacity.
  • Elevated performance.
  • Improved endocrine response to exercise.
  • Decreased soreness following exercise.

Research On Phosphatidylserine And Athletes

Study #1: Phosphatidylserine Supplementation Improves Cycling Exercise Capacity

A 2006 study conducted by Kingsley et al. discovered that cyclists who supplemented with 750mg of phosphatidylserine for 10 days had a significant improvement in time to exhaustion when cycling at 85% VO2 max during a staged time trial.

Study #2: Phosphatidylserine Supplementation Improves Running Time To Exhaustion

A 2005 study conducted by Kingsley et al. found runners who took 750mg of phosphatidylserine for 10 days were able to improve time to exhaustion by 4% during two separate exhaustive time trials.

Study #3: Phosphatidylserine Can Combat Exercise Induced Stress

A 2008 double-blinded, placebo-controlled, cross-over design study conducted by Starks et al. discovered subjects who supplemented with 600mg of phosphatidylserine for 10 days had lower cortisol levels than the placebo group after a 15-minute progressive cycle ergometer test (65-85% VO2 max).

The scientists concluded “that PS is an effective supplement for combating exercise-induced stress and preventing the physiological deterioration that can accompany too much exercise. PS supplementation promotes a desired hormonal status for athletes by blunting increases in cortisol levels.”

Study #4: Phosphatidylserine Supplementation Increases Cognitive Function Prior To Exercise

A 2011 study conducted by Parker et al. found that subjects who consumed 400mg of phosphatidylserine for 14 days performed better than the placebo group on Profile Of Moods (POMS) and Serial Subtraction Test (SST) thus demonstrating the cognitive enhancing properties of PS supplementation.

How Long Does It Take For Phosphatidylserine To Work?

Phosphatidylserine, when supplemented acutely, is able to pass through the blood-brain barrier relatively quickly.  Most individuals will notice enhanced mental cognition and acuity within 15-30 minutes of ingesting phosphatidylserine.

Phosphatidylserine’s chronic benefits occur with daily supplementation when allowed to saturate the body’s PS stores.

When To Take Phosphatidylserine

When taken as a general “health” supplement, phosphatidylserine should be taken 3 times daily at a dose of 100mg (300mg total daily).

In athletic populations and for acute benefits as it relates to exercise performance, 200-400mg should be consumed 15-30 minutes before exercise.

Phosphatidylserine, Sleep, And Cortisol

Phosphatidylserine can improve sleep quality and latency by reducing the amount of cortisol in the body.  While cortisol levels can fluctuate naturally, it becomes a problem when it stays chronically elevated. This can cause feelings of stress, anxiousness, and restlessness that ultimately make it hard for individuals to fall asleep.

A 1992 study conducted by Monteleone et. al discovered men who supplemented with 800mg of PS for 10 days were able to reduce the amount of circulating cortisol in their bodies. The researchers concluded that “chronic oral administration of phosphatidylserine may counteract stress-induced activation of the hypothalamo-pituitary-adrenal axis in man.

Phosphatidylserine Side Effects

As a whole, phosphatidylserine is a very safe supplement. Studies examining up to 600mg daily for 12 weeks have not been associated with any adverse effects.

The Bottom Line On Phosphatidylserine

Phosphatidylserine is a safe, effective, and research demonstrated supplement that can provide benefits to both general and athletic populations. It can improve cognition and mental acuity, reduce cortisol, enhance exercise performance, and lead to better sleep quality. Individuals who want to supplement with PS should take 300-600mg daily taken in one to three doses.

About The Author Matt Mosman - Spearfish, South Dakota

Matt Mosman South Dakota

Matt Mosman (MS, CISSN, CSCS) is a research scientist, endurance athlete, and the founder and Chief Endurance Officer at EndurElite. Matt holds his B.S. in Exercise Science from Creighton University and his M.S. in Exercise Physiology from the University of California.  Matt and his family reside in Spearfish South Dakota where they enjoy running, mountain biking, camping, and all the outdoor adventures Spearfish has to offer.


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