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You should not take ginkgo biloba with any nonsteroidal anti-inflammatory drugs (NSAIDs) such as aspirin or ibuprofen because they also thin the blood. Combining the two may cause excessive bleeding. The same goes for blood thinners such as warfarin.
Huperzine-A, derived from the Chinese moss Huperzia seratta, is another herb that has been studied as a potential Alzheimer's therapy. It may also work as a brain booster in healthy people, but few studies have looked at that.
One study out of China showed that it improved memory and learning in a small group of students. "It has been used in China much more than it has in the U.S.," Sahelian says.
Huperzine-A appears to block an enzyme in the brain that breaks down acetylcholine, a neurotransmitter. Acetylcholine carries information across synapses, the space between brain cells. "More acetylcholine stays in the brain, and that's how it can be helpful in memory," Sahelian says.
Brain Food
Beyond herbs, a number of nutrients may work as brain boosters.
An omega-3 fatty acid found in fish oils, docosahexaenoic acid (DHA) is thought to be important to an infant's developing brain. DHA may also work as a brain booster by helping brain cells communicate, according to Sahelian.
"Interestingly, the lining of our brain cells is very highly concentrated with fatty acids, particularly DHA," he says.
One 1999 review of studies on DHA, published in the journal Pharmacological Research, found that the nutrient is essential to normal brain function, and that a diet rich in DHA improves learning, while a lack of DHA causes learning ability to suffer.
"Another one that I really like is aceytl-L-carnatine. That's becoming quite popular," Sahelian says.
Acetyl-L-carnitine may work as a brain booster by helping maintain brain cells. Not much is known about its effects in healthy people, but one study found that people with early Alzheimer's and mild memory impairment benefited from taking it.
Despite the lack of evidence, Sahelian says he thinks it improves mental focus and alertness. "I noticed the effect within two hours," he says. "It also makes one more motivated, and you can concentrate better and get things done faster."
DMAE (2-dimethylaminoethanol), also thought to alter levels of acetylcholine in the brain, is another one that Sahelian says he can get behind based on anecdotal evidence alone. There is little in the way of scientific data to support claims that it boosts brainpower.
Nevertheless, "Most people will notice within an hour or two of taking it that they're thinking faster and sharper and that they have better focus," he says.
He says that taking too much can cause side effects such as restlessness, irritability, and tension in the neck muscles.
Getting Smart
All these things are considered dietary supplements, not drugs, so they're not subject to the rigorous approval process that drugs are. The FDA limits the claims manufacturers can make about supplements to some degree, but you're largely left to judge for yourself.
If you're willing to shell out some cash -- for example, a bottle of 60 acetyl-L-carnitine capsules, at 250 mg, sells for about $20 -- you might find something you like. But it's a process of trial and error.
"It's difficult to predict how an individual will respond. There's no blood study or spinal tap or anything we can do that will tell us, 'Well, this is the perfect herb for you,'" Sahelian says.
Sahelian also points out that brain boosters won't help if you're sleep-deprived. "Deep sleep, out of anything, is probably the most important factor in preserving memory and clarity of thinking during the day," he says.
Published June 16, 2003.
SOURCES: Ray Sahelian, MD. Psychopharmacology, September 2000. Human Psychopharmacology, July 2001; January 2002. Psychopharmacology Bulletin, Summer 2002. The Cochrane Database of Systematic Reviews, 2002. Archives of Neurology, November 1998. Zhongguo Yao Li Xue Bao, July 1999. Pharmacological Research, September 1999. International Clinical Psychopharmacology, March 2003. FDA web site.