Choline, an amino acid, may protect the brain throughout life -- from the womb to very old age. Indeed, if your mother eats enough choline to satiate your fetal brain, you may enjoy a lifetime of superior intellect and not even have to worry about a declining memory as you get old. That's a remarkable new finding from laboratory animals, that researchers say may translate to humans, although such human studies have not been done.
What researchers have found is phenomenal: That giving rats choline halfway through pregnancy makes a permanent mark on the fetal brain -- dictating how its cells organize to mold and wire the brain, essentially building in an "excess memory capacity" that endures throughout life. In a series of experiments, scientists at Duke University Medical Center fed pregnant rats normal choline, extra choline, or no choline and then studied the mental functioning and brains of their offspring.
Clearly, the rats that got the extra choline in the womb had vastly superior brains; as infants and adults they displayed better memory and learning capabilities. Indeed, postmortem examinations revealed superbly efficient brain circuits for transmitting messages. The neurons in their hippocampus, the brain's memory processlng center, responded instantly to the tiniest electrical probe, indicating their brains were primed to learn rapidly. Awesome as it seems, the extra infusion of a single nutrient, choline, enabled nature to assemble a brain of extraordinary quality.
On the other hand, rats deprived of choline in utero had sluggish brains and impaired memory when they grew up.
Even more startling, as the high-choline offspring entered old age, their brain function remained undiminished. Their memory did not fade, as it did in rats not given choline prenatally. In very old age, choline-primed rats made only half as many memory errors when searching through mazes for food as did geriatric rats whose pregnant mothers had not been given extra choline.
"The ramifications of this could be profound. We've found that manipulating one single nutrient for a few days during gestation has a lifelong effect on how brains function. In theory, we could develop ways to significantly reduce age-related memory deficits." -- Dr. Scott Swartzwelder, neuropsychologist, Duke University
How could choline received before birth possibly be so powerful and long-lasting as to prevent memory deterioration in old age? Researchers speculate that choline might slow down the entire aging process, the brain included. Or, more probable, choline helps construct a brain with such a superior anatomical network of neurons and connections -- a large reserve of brain power and efficient memory processing -- that age-related erosion is insignificant to memory functioning later in life.
Choline does dramatically change the very structure of memory centers in the hippocampus and septum of the developing fetal brain, declares Dr. Steven Zeisel, M.D., a world expert on choline, and chairman of nutrition at the University of North Carolina School of Medicine at Chapel Hill. Dr. Zeisel and colleagues found that when choline is lacking, cell division in the fetal brain is reduced, cells migrate abnormally, and increasing numbers of brain cells die prematurely. "For the first time, we have shown that the very structure of the brain is influenced by what mothers eat during pregnancy. Mainly, the specific nutrient choline appears to be critical."
But what if your mother failed to give your fetal brain lots of choline? Will eating choline later as a child, adult, or in old age improve your mental functioning? It's a good bet, say experts, although you cannot count on choline to completely reorganize the way your brain circuits work. Still, birth does not put an end to the brain's need for choline.
Choline is particularly essential for infants, whose brains are still developing. So if a mother missed providing lots of choline in the womb, there is a second chance, Not surprisingly, breast milk, also depending on a mother's diet, is very rich in choline, which is one more brain-boosting reason to breast-feed. Infant formulas made from both cow's milk and soy are required to add choline, but they do not contain as much as human breast milk.
Breast-feeding is definitely preferred, and may make a difference in your baby's brain. "Because infant formulas vary so much from human breast milk," says Dr. Zeisel, "it's not unreasonable to worry that some differences in intellectual performance that we see could be due to changes in the availability of choline in utero and shortly after birth in some kids."
Besides building strong brains, choline is also vital in keeping brain cells functioning throughout life. For one thing, choline is a precursor (building block) for acetylcholine the neurotransmitter vital to encoding memory. When choline is in good supply, your neurons are more apt to make and release acetylcholine. Blocking production of acetylcholine in brain cells impairs memory; flooding brain cells with acetylcholine may overcome some memory deficits. That's the theory of some drugs used to treat Alzheimer's and dementia. Choline is a critical constituent of fat in brain cell membranes, influencing their structure and facilitating transmission of signals from the cell exterior to the nucleus, a momentous task. Additionally, choline helps suppress homocysteine in the blood that is associated with brain disturbances, memory damage, and even Alzheimer's, and strokes.
According to extensive research, choline improves memory and learning in many species, including rats, mice, mollusks, and humans. Of course, tests in laboratory animals do not prove that humans build brains the same way. But decades of research have been eerily accurate in making the leap from what happens in the brains of small mammals to how the human brain works. It's probable that if scientists discover a brain secret in other mammals, it will eventually be confirmed in humans. Growing new brain cells is a prime case in point: Thirty years before it was detected in humans, scientists had demonstrated it in laboratory animals.
It's unclear to what extent taking supplemental choline later in life may boost human memory or intellectual performance. Some studies find benefits; others do not. One recent experiment with eighty college students found improvement on tests of explicit memory in those who took 25 grams of lecithin that supplied 3750 milligrams of choline. There was no memory benefit from taking just ten grams of lecithin. Specifically, the students were better able to memorize a series of nonsense syllables about an hour and a half after taking the choline. Interestingly, the memory boost was greatest in "slow learners," leading researchers to suspect that the slow learners had subnormal levels of choline to begin with. Thus, a supplement corrected a slight deficiency.
This may mean, they said, that choline works best to improve memory in slow learners and the elderly who may have abnormally low choline. The double-blind controlled study was conducted by psychologists at several California universities, including Stanford.
Choline has boosted memory in older adults. Florence Safford, D.S.W., of Florida International University, had forty-one healthy people, ages fifty through eighty, take 500 milligrams of choline (found in two tablespoons of lecithin granules) every day for five weeks. She says they reported diminished memory lapses, such as forgetting names, misplacing items, remembering names on the tip of their tongue. Indeed, their memory lapses were about half those of comparable subjects not getting choline-lecithin--down from an average 35 lapses per week to 19 per week.
However other more rigorous double-blind studies have not found mental benefits in adults taking choline. One explanation: The choline in food or supplements that gets 1nto your bloodstream may not make it into your brain. Around middle age, the ability to transport choline from the blood to the brain tends to decline, say brain experts.
Regardless of whether high doses of choline hypes memory in adults, everybody still needs choline in the diet or through supplements for optimal brain functioning. Experts now consider choline an essential or required nutrient for all ages. Your body cannot make enough choline for optimum health.
You may be surprised to learn that egg yolk's are one of the highest and most reliable sources of choline. Thus, avoiding or severely restricting eggs may be harmful to brain functioning. The consumption of eggs has plummeted in the last thirty years due to warnings that the yolk is high in artery-clogging cholesterol. Consequently, intake of choline dropped sharply, since egg yolk is a major source of choline. Now, much new evidence shows that the amount of cholesterol in food is not a primary cause of raising cholesterol in the blood. High cholesterol is caused mainly by eating saturated fats, as in milk, butter, cheese, and meat.
Indeed, the egg is being exonerated. In April 1999, Harvard researchers proclaimed that an egg a day is unlikely to increase the risk of heart disease or strokes, according to a new analysis of the Harvard Nurses' Health Study and the Health Professionals Follow Up Study. Research tracked the egg consumption of 100,000 people for more than a decade. Harvard's Frank B. Hu,M.D., and colleagues, concluded that a daily egg is not harmful -- and may even help prevent heart disease, because eggs contain nutrients, including antioxidants, folic acid, other B vitamins, and unsaturated fat that may counteract any ill effect from the yolk's high cholesterol. Another one of those beneficial nutrients is choline.
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Adult men Adult women Pregnant women Lactating women |
550 mg 425 mg 450 mg 550 mg |
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Upper tolerable upper daily intake for: ChildrenAdults |
1000 mg 3500 mg |
SOURCE: National Academy of Sciences.
Best food sources: Egg yolks, peanuts, wheat germ, liver, meat, fish, milk, cheese, vegetables -- mainly broccoli, cabbage, and cauliflower.
What about supplements? If you want to take choline supplements, the best bet is lecithin rather than straight choline. High doses of pure choline leave you smelling "fishy," say experts. Lecithin, which is 20 percent choline, is a far better source. Lecithin comes in various forms (the scientific name is phosphatidylcholine), including granules that you can dissolve in a liquid, such as juice or milk, or sprinkle on cereal. A tablespoon of lecithin granules supplies about 250 milligrams of choline.
Lecithin supplements appear very safe, even at high doses, according to government tests.