Does Ginkgo Biloba Really Work?
Does Ginkgo work for boosting brainpower or slowing cognitive
decline in old age? This is a common question I get from subscribers
to the Brainpower Newsletter. I get complaints and comments too,
especially after recent news items claiming that science has
proven Ginkgo Biloba doesn't help our brains. People want to
know why I even mention such a "disputed" nootropic.
I'll explain why, but first let's look briefly at the science.
In a study reported in the International Journal of Geriatric
Psychiatry in December 2008, patients with early stage dementia
were given 120 milligrams of a standardized extract of Ginkgo
Biloba (or a placebo) for six months. No effect on cognitive
functioning was found. This and other studies suggested that
there was no beneficial effect from taking Ginkgo. But then,
in a study reported in the Journal of the Neurological Sciences
in August 2009, Ginkgo was found to increase cognitive test scores
in patients with Alzheimer's disease - when they were given 240
milligrams daily for 22 weeks.
A review of 34 placebo-controlled clinical trials of Ginkgo,
published in the German journal Zeitschrift fur Gerontologie
und Geriatrie in August 2008, found mixed results. Only 2 trials
showed no benefits, while 21 showed significant benefits. Looking
at these studies and reviews, it seems that Ginkgo can be useful,
and that the lack of measurable benefit in some may simply be
a matter of dosage.
The matter is further complicated by the fact that in some
studies, both with lab animals and humans, young individuals
didn't seem to be affected, while older participants did get
a benefit. But even here one study found that with higher dosages
younger participants saw benefits (reduced anxiety in one study).
Studies as to the efficacy of Ginkgo for boosting memory and
ability to concentrate have also had mixed results.
Finally, some people do experience side effects. In particular,
those who are on blood thinners such as warfarin or coumadin
should check with a doctor before taking Ginkgo.
So does Ginkgo Biloba work? It sure seems to in some contexts.
I feel a bit more clarity of thought after chewing a few leaves.
In any case it is relatively safe and inexpensive to try, so
it meets my criteria for self-experimentation. Readers are free
to make up their own minds, to wait for further clinical trials,
and to try it or not.
I will always report on possible brainpower boosters if they
are cheap and safe to try - and when the science is uncertain
I will report that as well. But neither my newsletter nor this
site is meant to be a scientific journal. As I have said before,
the serious science in many areas is often done only because
of the accumulating anecdotal evidence that comes from people
who are not afraid to try something new.
In the end Ginkgo may prove to have limited or no real benefits.
Who knows? But I do know this: If I read about another substance
that might increase brainpower, and upon further investigation
I find that it's safe and cheap, I'll risk my $20 and give it
a try - and then report my experiences and any other evidence
in the newsletter and on this website.
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