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by Parris M. Kidd, Ph.D.
GPC GlyceroPhosphoCholine
Natraceutical Breakthrough for Mental Performance
In these harsh times we find our daily lives more demanding than ever before. We’re more challenged to process large amounts of information, to be more productive on the job, to make important decisions that affect our lives for years to come. Our mental capacities are being sorely tested. We have to perform whether we want to or not.
Now we have help. GPC (GlyceroPhospho-Choline, pronounced gli-sero-fos-fo-ko-lean) is a nutrient that safely and naturally sharpens alertness, concentration and other functions of mental sharpness. After extensive clinical testing GPC has earned its place at the forefront of mental boosters. Complementing its proven and reliable effectiveness is GPC’s excellent record of safety. GPC is so integral to human nutrition that breast milk conveys generous quantities of it to the newborn.
GPC is naturally present in all the body’s cells and tissues, which feature makes it an orthomolecule. Orthomolecules are substances orthodox to the body: they are integral to the body’s normal metabolism. Human cells do produce GPC but probably the constant high requirement and sometimes excessive demand for this substance make supplementation useful.
So who besides babies can benefit from GPC? The answer is: just about everyone. GPC is a major source of choline, a substance recently classified as an “essential” nutrient, in that we have to get it with our diet in order?to stay healthy. Choline has three major life support functions. It is an important source of methyl groups, which are necessary for tissue renewal and repair. It?is a biochemical building block for AcetylCholine (ACh), a key nerve transmitter. And it is also a building block for two phospholipids that go into building cell membranes, the structural support for cell biochemistry (featured in our last issue). Thus everyone, whatever their age, needs choline.
Choline’s universal involvement in life processes accounts for its vitamin-like status. But for living cells, native (“free”) choline is actually difficult to handle—a biochemical hot potato. Free choline is chemically unstable in the watery medium of the cell interior or the blood. Consequently, the vast majority of the body’s choline occurs packaged into larger molecules that “buffer” it. Very little free choline is present in our tissues and fluids and foods from plants or animals generally carry very little. Instead, the phospholipids PC (PhosphatidylCholine) and Sph (sphingomyelin), along with GPC are the body’s choline reservoirs.
Unlike PC and Sph, GPC is really an “active choline” for the brain since it quickly and efficiently raises the brain’s choline levels to support ACh and numerous other biochemical demands. GPC is also the most convenient source of choline for brain phospholipids—it can be converted to PC or Sph without major energy investment. And GPC is an important osmotic buffer in the brain (as well as in the liver and kidneys).
GPC’s unique capacity to fulfill the brain’s high demand for choline equivalents, taken together with the central importance of choline for life processes, suggests GPC supplementation should have measurable clinical benefit. It does.
GPC has been clinically evaluated in controlled trials. A minimum 19 clinical trials have been done with GPC. Thirteen of the trials were randomized and controlled, seven also double-blind. All studied measurable features of mental performance and all produced positive findings. The vast majority of the subjects who were given GPC experienced clinically meaningful benefit.
GPC benefits mental performance in young, healthy people. Two double-blind?trials were conducted with male and female volunteers aged 19–38 years, using the scopolamine amnesia model. The drug scopolamine depletes AcetylCholine from the brain and induces a kind of amnesia (lowering of attentiveness, recall capacity and overall mental performance). This can be reversed by restoring ACh levels in the brain. Dosing with GPC for 7–10 days prior to the scopolamine exposure partially protects against the amnesia effect, while placebo does not.
In the first double-blind GPC-scopolamine trial the subjects preloaded with GPC by mouth tested significantly better than placebo on recall performance (remembering 20 simple words read to them aloud; also called immediate learning). GPC also improved recall performance in the subjects who did not receive scopolamine—that is, it improved the baseline recall capacities of these young people. GPC also significantly protected against the attention deficits induced by scopolamine.
In the second double-blind GPC-scopolamine trial, healthy men and women aged 22–33 were the subjects. GPC by mouth was compared against two drugs, idebenone and aniracetam. After seven days of pretreatment, again GPC helped?protect recall learning against scopolamine and it worked better than the two drugs.?GPC also protected the “working memory” (a combination of reasoning and attention), again better than did the drugs.
In middle-aged subjects, GPC improved a number of mental performance measures in controlled trials. Along with improving reaction time, which is related to ACh nerve pathways, GPC also improved the sensitivity of the visual cortex, the brain’s cortical zone that reacts to stimulation through the eyes. This is a useful index for overall brain improvement by a test agent. GPC improves the EEG (Electro-EncephaloGraphic) electrical patterns of the middle-aged brain and the young healthy brain as well.
GPC shows great promise to improve brain trauma of whatever type. One huge study on stroke recovery involved 176 hospital centers within Italy. For ethical reasons (the possibility of death if given placebo) this study could not be conventionally controlled; all subjects received GPC. Starting with 2044 hospitalized patients, a total 2004 completed six months of close observation and functional testing while on GPC. At the end of the study the investigators judged GPC had significantly helped more than 95 percent of the patients.
Fourteen of the seriously ill patients in this study (0.68 percent) were forced to withdraw due to GPC adverse effects: heartburn, nausea/vomiting, excitation/insomnia, diarrhea, dizziness, skin rash, confusion or faintness. All but four of these withdrawals occurred during the first month, when the patients were sickest. Blood analyses and other monitoring (blood pressure, heart rate, kidney and liver functions) revealed no abnormal changes from GPC over the six months of study. The investigators concluded GPC had excellent tolerability.
GPC also improved mental functioning in subjects impaired from heart surgery. It improved mental performance in subjects with moderate to severe brain damage?related either to poor circulation (“vascular dementia”) or to other, unknown problems (Alzheimer’s and other dementias). GPC consistently improved both cognitive processing and mood in such subjects.
GPC has been compared against several other “brain-booster” nutrients and drugs for efficacy. It outdid citicoline (CDP-choline, another PC precursor) in three trials. In a trial on patients with probable Alzheimer’s dementia, GPC performed better than acetylcarnitine, which is another ACh building block. Neither of these nutrients worked well for the more advanced Alzheimer’s cases, but GPC?was roughly twice as effective (benefiting 29 percent of advanced cases versus 15 percent for acetylcarnitine).
Not all the clinical trials involved giving GPC by mouth. Many gave GPC “i.m.”—intramuscularly, by injection into muscle. Comparisons between similar trials done by the different routes—oral vs. intramuscular—combined with analyses of GPC’s uptake patterns by the two routes, led to the conclusion that 1200 milligrams (mg) of GPC per day, by mouth, is a reasonable intake level for good clinical benefit.
This oral intake level need not be the highest daily intake allowed for GPC, however. The substance is very safe to take and is extremely well tolerated. Of the more than 3000 patients who have received GPC in clinical trials up to this point, not one serious adverse effect has been reported. Intakes of 2000 mg per day are known to be well tolerated and will more quickly elevate GPC levels within the brain. On the other hand, a daily intake of 600 mg GPC per day significantly raises brain choline levels and could be a cost-effective “maintenance” intake.
Though technically not a full-fledged phospholipid, GPC is a major biochemical resource for their bio-synthesis and shares their exceptional safety record. Phospholipids are orthomolecules required for cell membrane formation, maintenance and repair following damage. GPC is not itself incorporated into the membranes since it is too highly water soluble. Instead it builds up to high levels in the cytoplasm (the basis for its osmotic buffer role) and is drawn upon to make new?phospholipid as necessary.
GPC may be valuable for those of us whose brains are simply aging without (or not yet showing) apparent disease. Several studies, some of complicated design, were carried out with GPC on old and young individuals, to assess whether it could achieve restoration of growth hormone (GH) production by the pituitary gland.
GH release from the pituitary (the body’s “master” hormone-producing gland) coordinates maintenance and renewal activities throughout the body on a daily basis. As people reach middle age their GH production drops and in some older people GH can be totally absent from the blood. But GPC was found to improve GH release when co-injected into older individuals with GHRH, the Growth Hormone Releasing Hormone. The addition of GPC markedly improved GH release over GHRH’s effect by itself. As expected, GPC’s effect was better in old (though healthy) volunteers than in the healthy young.
Other research indicates GPC used by itself may revitalize the pituitary gland as a whole, since it may boost another very important hormone—thyroid-stimulating hormone (TSH)—and probably others, in addition to GPC. This research is still preliminary. Further clinical study is required but for these crucial antiaging applications GPC holds great promise.
A large body of experimental animal research strongly suggests GPC may very well have the capacity to revitalize the aging human brain. In aging rats GPC stimulates the GH-pituitary axis, protects against loss of neurotransmitter receptors with aging, conserves receptors for nerve growth factor (NGF) and has other antiaging effects. Whether the potential human recipient is young, middle aged or elderly, healthy or with disease, GPC is a nutraceutical breakthrough for mental performance.
References available upon request from totalhealth.
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