GPC (GlyceroPhosphoCholine) and PS (PhosphatidylSerine) are phospholipid nutrients intensively researched for their benefits to diverse human brain functions.* These nutrients naturally complement each other: GPC reaches very high concentrations inside cells; PS is a building block for cell membranes that generate the brain’s energy and electricity.* Numerous double-blind trials catalog the benefits of GPC and PS for people of all ages.*
Serving Size 2 capsule
Servings Per Container 30 Servings
Amount Per Serving %DV
GlyceroPhosphoCholine (GPC) 300 mg †
PhosphatidylSerine (PS) 100 mg †
† Daily Value not established.
Other Ingredients: Dicalcium phosphate, modified cellulose (vegetarian capsule), silicon dioxide, magnesium silicate, magnesium stearate (vegetable source).
Suggested Adult Use: Take 2 capsules twice daily between meals, not later than 4 pm. Intakes up to 6 capsules per day may be beneficial, as recommended by a nutritionally informed physician.
Non-GMO & Gluten Free
Store in cool dry place
Natural Brain Enhancerscombines the two nutrients best validated for supporting brain health and mental performance at any age. GPC (GlyceroPhosphoCholine) and PS (PhosphatidylSerine) are validated by 34 double-blind (DB) trials and hundreds of other human and animal studies.1,2
GPC and PS are both phospholipid (fos-fo-lip-id) nutrients, essential to brain cell structure and function, but have differing molecular actions that naturally complement each other. GPC operates in the cell water phase (“cytoplasm”), while PS works within cell membranes. Both these nutrients are naturally present in all the cells of the body and are fundamental to life.
GPC, Vital For Mind and Body*
GPC has been an important brain nutrient in Europe since the 1980s, and in North America since 1997. It has many important nutritional roles, including being the best dietary source of choline, recently confirmed to be a dietarily essential nutrient.3 It helps prevent tissue buildup of urea, a metabolic waste product. This is just part of GPC’s broader, very important osmotic function in helping to keep water pressures equalized between the cell’s interior and the outside environment.4 GPC, along with PS, is concentrated in human breast milk.1,2,5
Double blind (“DB”) clinical trials and experimental findings document GPC’s many important benefits6-21:
* Supports healthy memory, learning, focus, and other cognitive functions, at all ages.
* Improves learning and behavior in children.
* Sharpens attention and word recall in young, healthy adults.
* Supports healthy mental performance in middle-aged people.
* Supports memory, learning, mood, and sociability in the elderly.
* Assists the kidneys and other organs to manage metabolic wastes.
In two DB trials with young, healthy subjects, GPC supported and even enhanced crucial cognitive functions.6,7 Volunteers were pretreated with GPC or a placebo, then injected with the chemical scopolamine. This can cause a temporary cognitive paralysis — amnesia. But giving GPC in advance acted as a countermeasure against the expected cognitive paralysis. Verbal learning was maintained all through the 6-hour amnesia period. Attention, verbal learning, and memory benefited for at least the first 3 hours. GPC also partially supported “working memory,” the ability to concentrate in the presence of distraction.
In these young, healthy subjects GPC surprisingly even boosted word recall above the healthy starting level.6 To enhance normal mental performance in young, healthy people is a very rare quality and establishes GPC as a premier brain nutrient.7,8
Revitalizes the Aging Brain*
GPC has been subjected to many clinical trials with subjects older than 50 years. In 2001, a “meta-analysis” after pooling of the clinical data concluded that GPC was helpful for attention and memory in this aging population.9 A further meta-analysis in 2007 reconfirmed these findings.10 Data from over 1000 individuals assessed in several psychometric test systems showed that GPC offered support for mood and occasional fatigue in addition to attention, memory and other cognitive functions.9,10
GPC can help revitalize the brain.11-21 In one large DB trial that involved 261 elderly subjects, GPC improved cognition, behavior and activities of daily living.11 In animal studies, GPC when given by mouth significantly supported brain circuits confronted with toxic chemical exposure or subjected to mechanical damage.1
Integrates Brain With Body*
The body uses GPC to make at least three functionally diverse nutrients—choline, acetylcholine, and phosphatidylcholine (PC).1 These three GPC metabolites are constantly needed for supporting (among other functions) healthy gene regulation, mental and visual performance, the brain’s stimulation of voluntary muscles, and the non-conscious coordination of internal organ functions by the autonomic nervous system. GPC and its metabolites are fundamentally involved in growth, renewal and overall health maintenance, across the human lifespan.
Choline is a vitamin-like nutrient that is crucial to health, most especially as a source of methyl groups for healthy gene regulation (epigenetics).22 Choline also is used to make acetylcholine (ACh), which is not just the brain’s most abundant chemical transmitter but a universal messenger substance serving the other organs. ACh serves both conscious brain functions and non-conscious body functions (such as the heartbeat and intestinal peristalsis) via the autonomic nervous system.23
GPC is the best dietary extended-release source of choline. The choline salts commonly used in dietary supplements produce just a brief spike of choline in the blood, but GPC rapidly raises blood choline and keeps it elevated for up to 10 hours.3 This Natural Brain Enhancers formulation meets U.S. Food and Drug Administration (FDA) guidelines as an excellent source of choline.
The PC that can be derived from GPC is a major cell membrane building block.1,23 Cell membranes are the universal, dynamic molecular assemblies that cells use for the majority of their functions.1,2,23 Our brain cells and other cell types can readily use GPC to make fully functional membrane PC, with minimal expenditure of energy. Supplementing with GPC therefore helps ensure our cells can make new membrane mass from PC, in order to make energy, to grow, and to replace membranes lost to damage.
Promotes Active Living and Healthy Aging*
GPC’s primary actions support a further cascade of beneficial actions. By supporting the brain’s acetylcholine status it supports pituitary hormone rhythms.20 Its osmotic and urea-buffering actions support all the organs, but especially the kidneys which typically accumulate it to very high levels.4 GPC is so versatile, it even helps the brain cells respond to NGF (nerve growth factor), an important messenger for nerve tissue renewal.1,21
GPC is truly vital at all stages of life. Its unique profile of protective, metabolic, and biochemical attributes help account for its proven contributions to mind-body integration, to active living and to healthy aging.
PS, Vital Lipid for Memory, Mood and Stress*
PS also emerged as an important brain nutrient in Europe. It has been proven through 30 double-blind trials and numerous other human and animal studies.2,24-45 In 2003 the U.S. Food and Drug Administration (FDA) granted PS two Qualified Health Claims24:
Consumption of phosphatidylserine may reduce the risk of dementia in the elderly. Very limited and preliminary scientific research suggests that phosphatidylserine may reduce the risk of dementia in the elderly. FDA concludes that there is little scientific evidence supporting this claim.
Proven PS brain benefits include24-46:
• Enhances memory, learning and other cognitive functions in over-50 healthy subjects, when compared to others in their age group.25-33,43,44,46
• Improves behavior, sociability and other quality of life indicators in the elderly.26-32,41
• Facilitates brain vitality, supports brain energetics.33
• Helps manage stress, whether emotional or physical in origin.34-42
• Promotes a balanced mood and is useful for restlessness or nervous tension, both in the young and the elderly.37-39,41,42,45
• Supports normal development of attention and behavior in childhood.45
Initially, PS was produced from cow brains, but after “mad cow” disease contaminated cattle herds soy became the source of commercial PS. Soy PS has been proven effective in at least 11 clinical trials.35-41,44-47
Supports Memory, Learning, Other Higher Brain Functions*
In DB trials with over-50 subjects, PS was proven to slow age-related declines of memory, learning, concentration, and other cognitive functions.25-33,44,45,47 Renowned memory expert Dr. Thomas Crook coordinated two of the most informative trials.25,26
The first Crook trial studied people older than 50 who were healthy but did not have ideal memory for their age.25 The researchers concluded that PS have may “turned back the clock” on ageing in the brain. PS taken by mouth for 3 months may have restored as much as 12 years’ worth of memory and other cognitive functions: a subject who first tested at a “cognitive age” equivalent to a 64-year-old could later test at a cognitive age of 52 years.
In the second Crook DB trial, PS helped those with mild memory problems associated with aging.26 The sum total of all the memory trials with PS suggests consistent benefit for individuals whose memory could be better, but is not disturbing their daily existence.
Benefits Mood and Stress Management*
PS has improved nervous irritability and sociability in elderly, young university students, and children. In a British DB trial,42 university students took PS or a placebo for 10 days, then had to do complicated arithmetic calculations without calculators. Taking PS supported the mood and self-confidence of the most restless in this group.
PS also can help combat physical stress, such as intense physical exercise. For bicyclists doing long rides, PS seemed to promote better mood, faster heart rate recovery, and increased endurance time.20 At higher PS intakes, cyclists may avoid experiencing elevation of the stress hormone cortisol.34 Golfers after taking PS for six weeks showed significantly improved accuracy on their drives.37 Weightlifters reported noticeably less muscle soreness and markedly better wellbeing from taking PS, as compared to placebo.40
Key Cell Membrane Builder*
Every human cell has a membrane system that is both an outer border for the cell AND creates functionally specialized compartments within the cell.23,47 Cell membranes drive both the production of energy (mostly in the mitochondria) and its utilization to sustain the body’s life processes.23,47 PS is a foremost molecular building block for both the outer and the inner cell membranes.2,23
In a brain imaging study conducted using PET (Positron Emission Tomography), supplementation with PS was found to markedly enhance brain energy production.33 The brain is more enriched in PS than is any other organ. PS is crucial for the brain’s electrical activity via the individual nerve cells. PS also supports many of the brain’s major nerve transmitter systems by facilitating their membrane receptors. PS also (similarly to GPC) supports nerve growth factor actions, by helping to conserve NGF receptors in the nerve cell membranes.2
* These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease.
Do you test your products for heavy metals and pesticides, etc.?
We receive Certificates of Analysis from all our ingredient suppliers. These certificates specify the maximum allowable amounts for any impurities and report the precise amounts of impurities present. We always strive to use the purest ingredients available.
Can Natural Brain Enhancers be taken in the morning on the empty stomach?
Yes. GPC was administered on an empty stomach in the clinical trials and has increased absorption when taken without food.
Is GPC water or fat soluble?
GPC is water soluble.
Why should I take GPC between meals?
GPC is better absorbed when taken without food. In the clinical trials with GPC it was routinely taken between meals.
The amount of PS in the Natural Brain Enhancers is 100 mg. Is it the same as our regular PS.100 mg of PS from 500 mg of Phospholipid Matrix? Is the rest of the Phospholipid Matrix in the NBE as well?
The PS in NBE is the same as the PS in the other DRB products, and does have the phospholipid matrix as well.
What is HPLC?
HPLC stands for "High Performance Liquid Chromatography." This is an analytical lab testing method that is used to quantify the active ingredients. It is considered to be a very sensitive and accurate test. HPLC testing is a tool recognized as a quality benchmark for herbal extracts.
Since Doctor's Best does not manufacture its supplements, how are the purity and integrity of supplements verified? In addition, how are your prices lower than other brands? Does this mean that quality is being compromised?
Doctor's Best supplements are manufactured in the US at cGMP (current Good Manufacturing Practice) certified facilities. All of our manufacturers and suppliers go through our vendor qualification program, which includes inspections and testing, before we agree to work with them. Our finished products have also been tested at the raw material level, in process, and as a finished product to ensure safety and quality. We place the highest importance on safety and quality and do not compromise for the sake of a better price point. The price points are lower because of production size and the overall business structure. We also place great importance on making our supplements available and affordable to those who need them most.
What is cellulose and modified cellulose produced from?
Vegetarian capsules are made from cellulose, a non-animal product, which complies with cultural and/or vegetarian requirements. The capsules are certified with Kosher and Halal. Cellulose is derived from high quality wood pulp.
It seems that information is now out claiming that magnesium stearate is a form of, or implicated in, trans fat, which everyone now regards as being bad. Why does Doctor’s Best uses magnesium stearate in its products?
Magnesium Stearate is used to work as a lubricant in the formula. Magnesium Stearate is a salt of stearic acid. Stearic acid is a saturated fatty acid. A trans fatty acid (commonly shortened to trans fat) is an unsaturated fatty acid molecule. Stearic acid, being a saturated fatty acid, is not a trans fat. The magnesium stearate used in Doctor’s Best products is vegetable sourced from palm oil.
Why is silicon dioxide used as an excipient in DRB products?
Silicon Dioxide is commonly used as a flow agent in supplements. It also works as an anti-caking agent, and is added as an ingredient in foods, many multivitamins and mineral supplements because silicon is necessary for good health and is a necessary nutrient for the health of skin, hair, nails and bones.
Should I be concerned when I see that Silicon Dioxide has been used as an excipient in DRB products?
According to numerous studies reviewed to date on this long-term Generally Recognized As Safe (GRAS) listed food additive, the following was found:
The oral toxicity in mice is greater than (>) 5 grams/kilogram of body weight (Kimmerle 1968), or greater than 350 grams in one dose in humans based on allometric comparisons between mice and humans.
A single dose of 2.5 grams of amorphous polymeric silicon dioxide to human volunteers did not significantly raise the SiO2 excretion in the urine thus suggesting poor absorption of the compound (silicon dioxide)--(Langendorf 1966). Less than one one-hundredth (1000th) of the dose was found in urine, suggesting extremely poor absorption--(Langendorf 1966).
This would suggest that there is no scientific reason to eliminate silicon dioxide as an excipient at the very low levels found in dietary supplements.
For further information re: Silicon dioxide, see "Minerals, Trace Elements and Human Health, 4th Edition."
Why do you use soy lecithin in some of your products?
Soy lecithin is used as an emulsifier/stabilizer.
What are the other ingredients and why are they used?
These are used as flow agents and aid in the production to keep the machinery running smoothly and the capsules filling correctly. Similarly for the croscarmellose sodium, which is cellulose (sourced from the cell walls of green plants), and is used to help the tablet to dissolve in the stomach.
Is there a limit to how many vitamins can be taken safely in one day?
While our bodies need vitamins and minerals, like other things, if taken in large amounts they may adversely affect health. Large amounts of anything can be toxic. It is important to follow all label directions and discuss any concerns with your physician.
I am somewhat confused on how to take the DRB products. On many of the labels the Suggested Adult Use will list something along the lines of: Take 2 capsules daily, but it does not state whether they should be taken together or separately. What is the correct usage?
Unless otherwise specified on the label, the product may be taken together or separately.
What is modified cellulose and is it safe?
The cellulose is derived from alpha cellulose from softwood pulp. This softwood pulp may be derived from hemlock, spruce or other soft woods. It is made by cooking raw plant fiber in an aqueous solution to separate the cellulose, and then purified. It then goes through extra processing to further break down the fiber. The finished product contains no residual solvents. Excipients are needed to make the materials flow into the capsule and are extremely minute in amounts and are safe.