One of the most scientifically promising memory enhancers is a substance with the tongue-twisting name phosphatidylserine (fos’fuh tid’ill ser een). Most experts simply call it PS. It’s a fatty nutrient present in all cell membranes, but most concentrated in brain cells. It has no trouble zipping through the blood-brain barrier. It gets to the brain within minutes after it’s absorbed. This is very good news for those whose brains need more PS. And that is about everybody over age forty.
“I’ve tested close to a hundred compounds for their effects on human memory, and phosphatidylserine (PS) is the most impressive one I’ve found so far:” —Thomas Crook, former chief of the Geriatric Psychopharmacology Program at the National Institute of Mental Health and author of The Memory Cure
PS is one of the few nonprescription memory boosters that commands respect from hard-core brain investigators, because numerous studies, most done in the early 1990s, indicate it can rejuvenate memory. Reportedly, more than twenty-five human studies, about half of them doubleblind—the “gold standard” for testing—have found phosphatidylserine effective in revving up failing memory.
PS’s most credentialed champion is an authority on memory loss, Thomas H. Crook III, Ph.D. For fourteen years he was a research psychologist at the prestigious National Institute of Mental Health. As president of Psychologix, Inc., a research organization in Scottsdale, Arizona, he now conducts private research for pharmaceutical companies. It was Dr. Crook’s 1991 study that propelled phosphatidylserine to scientific notice. PS at the time was considered a prescription drug; it was later reclassified as an over-the-counter “dietary supplement.” In collaboration with researchers at Vanderbilt University School of Medicine and Stanford University, Dr. Crook studied the memory effects of PS on 149 persons, ages fifty to seventy-five. All had typical age-related memory impairment. Initially, the investigators were “extremely skeptical,” because they knew of no substance that could delay age-related memory loss, let alone reverse it. They soon decided PS was unique.
ERASES MEMORY DECLINE
For twelve weeks, half of the subjects took 100 milligrams of PS three times a day at mealtimes. The others took an inactive look-alike “sugar pill” or placebo. A11 subjects took a battery of neuropsychological tests at the start of the study and at three-week intervals. By the end of the study it was clear that those taking PS scored about 30 percent higher on tests of memory and learning. Further, PS takers with the worst memory deficits benefited the most. They were better at remembering names, faces, telephone numbers, and recalling paragraphs; their concentration also improved. The investigators concluded that PS shaved twelve years off the normal expected decline in specific aspects of memory performance! In short, if a person’s “cognitive age” for remembering faces was equivalent to age sixty-four, PS reversed it to age fifty-two—a year’s rollback for each week of taking the supplement. Further, the memory hike persisted for a month after subjects stopped taking PS.
“PS is not a magic bullet,” says Dr. Crook. “It’s not like you’re seventy-five and take it and you become twenty-five. But it is the first thing we’ve ever seen of many, many compounds that does have a clear measurable effect—and that effect is about twelve years of rolling back the clock. I really firmly believe that PS can roll back virtually all age-related memory impairment.”
Extensive foreign research supports Dr. Crook’s findings. Since the early 1980s, Italian investigators have used PS widely to revitalize memory in older persons. One of the most impressive double-blind studies was done in 1987 by researchers at Italy’s University of Catania. For three months 170 patients with moderately impaired cognitive function took either a daily PS dose of 300 milligrams or a placebo. Those getting PS surpassed the placebo group on neuropsychological tests measuring cognitive function, including memory. In two memory measures—semantic association ability and verbal fluency—PS takers scored 50 percent higher than placebo takers.
The largest double-blind Italian study of 425 older persons with moderate to severe intellectual decline showed that PS (300 milligrams daily for six months) improved scores on tests of total recall, long-term memory storage, and long-term retrieval of learned information. PS also bolstered communication and social interaction and lessened apathy and withdrawal.
“As laboratory rats reach middle age, they are less able to negotiate mazes. If they take PS, they stay smart into old age.”
—Parris M. Kidd, Ph.D., authority on PS, consultant for Lucas Meyer, makers of PS
What about Alzheimer’s disease? Not surprisingly, PS has been tested on people with dementia and Alzheimer’s. It may help in some cases, but overall, it has not proved as effective in treating Alzheimer’s, especially in the advanced stages, as in rejuvenating memory in ordinary people without the disease. For example, in 1992 Dr. Crook and colleagues at Vanderbilt University gave PS to patients with Alzheimer’s; they concluded it did boost cognitive functioning in the early stages of the disease. But in those with more advanced Alzheimer’s any PS-induced cognitive improvements were extremely modest and subtle.
Dr. Crook calls PS an ideal “memory cure” for the precise type memory decline that is typical after middle age. It’s unlikely PS will cure Alzheimer’s. Nor will it give you a super memory you never had before. But it may help restore the memory you would have had if normal aging had not eroded it.
BOTTOM LINE: PS may slow, stop, or restore memory losses due to normal aging.
SOYBEAN PS—BETTER YET
Before the “mad cow disease” scare, PS supplements were derived from cow brains, and most early studies were done with this so-called bovine PS. Today, PS is derived from soybeans entirely, and about 95 percent of it sold as a supplement is made by one company, Lucas Meyer in Decatur, Illinois, under the trademark Leci-PS. It is then packaged by a hundred or so individual companies and sold under many different brands. Since much of the evidence for PS effectiveness came from animal-type PS, the question arises: Is the current PS made from plants—soybeansequally effective?
Dr. Crook proclaims soy-type PS supplements identical in memory-boosting powers, even superior in some aspects, to the formerly used bovine PS. A recent double-blind test was an endorsement of soy Leci-PS. Dr. Crook found that people with memory troubles who took 300 milligrams a day of soybean PS (Leci PSTM) for twelve weeks demonstrated striking improvement: Compared with placebo-takers, their ability to learn and remember written information jumped 33 percent; remembering names immediately after an introduction skyrocketed 24 percent; recalling names one hour after introduction rose 33 percent over the placebo group.
Here’s what that means in years of memory rejuvenation. Dr. Crook figures that taking soy PS rolled back the clock fourteen years in remembering names after introduction, twelve years in learning and recalling written information, seven years in recognizing someone previously seen, and four years in dialing a ten-digit telephone number from memory—all within three months.
How does PS work? It basically energizes or revs up the brain. Proof positive of PS’s global impact on brain performance comes from PET scans and electroencephalogram (EEG) readings. Even in young men, injecting phosphatidylserine intravenously boosted alpha brain rhythms an average 15 to 20 percent, as shown on EEGs; such alpha activity is typically lower in aged and cognitively impaired brains.
In older subjects with mild memory problems oral doses of PS (300 milligrams daily) boosted sagging EEG “power” values to almost normal; scores on cognitive tests went up accordingly.
Most remarkable, German neurologists at the Max Planck Institute in Cologne did PET scans before and after giving 500 milligrams a day of PS for three weeks to patients with probable Alzheimer’s disease. While subjects took a mental test, PET scans recorded an increased “activation” of the brain. Before PS, the brain images were a calm sea of blue with only a few tiny dots of yellow and red, signifying low levels of glucose metabolism and brain activity. After PS treatment, the brain images are ablaze with large bright yellow patches and red dots, clearly illustrating a huge jump in activity and glucose metabolism in various regions of the brain. The greater brain activity induced by PS corresponded with higher scores on tests of cognitive functioning.
It is thought that the brain’s increased energy comes because PS enhances message transmission in nerve cells. Studies show PS raises levels of some neurotransmitters, particularly the memory-booster acetylcholine and dopamine; it also speeds up conduction of nerve impulses and modifies the structure and fatty consistency of neuron membranes and receptors, making neurotransmitters more efficient, thus facilitating cell to cell communication. PS also helps block the erosion of dendrite connections that normally occurs during aging. And it even helps protect cell membranes from free-radical damage.
What’s the right dose? The standard dose in tests is a 100 milligram pill taken three times a day (at mealtimes) for a total daily dose of 300 milligrams. That’s what Dr. Crook, age fifty-five, takes to protect his memory from age-related decline, and recommends for at least the first month. After that you can drop to one 100-milligram pill per day, or you can continue at 300 milligrams per day. Unfortunately, PS is expensive, about $1 per 100-milligram pill, which adds up to $90 per month for the high dose. An alternative: Start and continue with just 100 milligrams per day, if that is more affordable. The difference, says Dr. Crook: You should see improvement on the higher 300 milligram dose after three or four weeks. The lower 100 milligram dose may take eight or ten weeks to produce a memory boost.
What type PS? PS is widely available in health food stores, drugstores, and some supermarkets. It comes in either gel capsule or pill and is packaged under more than 100 different brands. Look for the trademark Leci-PS on the label or package; this assures you it contains the right stuff. Analyses of PS from other manufacturers have revealed poor quality and impurities. Fortunately, since almost all the soy PS made is Leci-PSTM, it’s hard to go wrong, and it’s okay to buy the least expensive brand. Packagers sell it for varying prices.
How safe is it? PS’s safety record is impressive. Although millions of Italians have taken PS for twenty years, there are no reports of significant side effects or even of interactions with pharmaceutical drugs. However, PS authority Dr. Parris Kidd cautions that in rare cases, downing high doses-200 milligrams or more of PS at one time—might cause nausea. To avoid this possibility, take PS with meals, he advises. Taking it just before going to bed might delay your falling asleep, Dr. Kidd adds.
What about food? You eat small amounts of PS in fish, soy foods, rice, and green leafy vegetables. But it’s probably not enough to protect your memory from the wounds of aging after middle age.