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Berkeley Wellness Alerts
April 6, 2010 | Comments: 2
Ginkgo: An Herb to Remember?
Many people take ginkgo to sharpen their memory and concentration, as well as for other positive effects on mind and body. Should you believe these claims or forget about them?
What it is: A centuries-old Chinese herbal medicine, ginkgo comes from the dried leaves of the maidenhair tree (Ginkgo biloba). It contains a complex mix of compounds. Like aspirin, it can keep blood clots from forming and may increase blood flow. Ginkgo has become one of the top-selling herbal products.
What the studies show: Ginkgo made headlines a dozen years ago when a study found that it improved mental and social functioning in some people with Alzheimer’s disease, though the effects were small and limited in duration. The study looked only at people with dementia, but many healthy people assume that ginkgo will boost their brain power—something that has never been demonstrated.
In fact, a review by the Cochrane Collaboration in 2007 looked at 35 studies and concluded that the overall evidence for ginkgo as a treatment for dementia or cognitive impairment is “inconsistent and unconvincing.”
Few studies have looked at ginkgo’s effects on normal age-related memory decline, and they have come up with mostly disappointing results. Notably, the largest and longest clinical trial ever to assess whether ginkgo could help prevent dementia appeared in the Journal of the American Medical Association in 2008. The six-year study looked at more than 1,500 people 75 and older, none of whom had dementia at the outset. The herb, taken twice a day in standardized doses, did not reduce the incidence of dementia, including Alzheimer’s. An editorial accompanying the study noted that it added to the “substantial body of evidence” showing similar findings. Moreover, in late 2009 a follow-up study in the same journal found that the ginkgo supplements did not slow the rate of cognitive decline or memory loss in any way.
Bottom line: Though ginkgo is one of the best-studied herbs, there is no convincing evidence it has any effect on memory or other mental functions in healthy older people. That is, ginkgo doesn’t sharpen an already-clear mind, help prevent what is considered normal age-related memory loss, or delay or prevent dementia. Nor is there evidence that ginkgo helps treat tinnitus or intermittent claudication, as is sometimes claimed. If you or a family member has Alzheimer’s or another dementia, talk to your doctor about trying ginkgo, but keep in mind that drug treatments may be better.
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Greetings Unfortunatley, this latest alert concerning Gingko, is as suspect as nearly all previous alerts presented to us by the Berkeley Wellness site. Nearly all your comments about "supplements," i.e. that dreaded "alternative" medicine, are either filled with outright rejection of the substance, or accompanied by grave suspicions concerning their use. This is precisely the way so-called Alternative medicine sites, newsletters, researchers, doctors, etc., describe conventional medicine and its promotion of phramacetuticals. There is no hope with this situation, for anyone that longs for clear and level-headed presentation of the facts; of the evidence.
How can this hopeless situation be addressed? Let me suggest an impossible solution. Impossible, because in the course of presenting it to you, you'll see the extent and nature of your bias, in favor of conventional medicine.
In this impossible future, simply seek out a good representative from the Alternative side, to respond to your comments about supplements, or other "alt" measures. Those of your readers, that can make head or tails throughout these debates, will benefit immensely. Those that cannot, are mindlessly following your alterts, in any case.
I remain a subscriber, JP
Posted by: johnp | April 11, 2010 1:54 AM
Unfortunately, recent studies on ginkgo have produced negative results. Our reviews are "evidence-based. Thus our Editorial Board reviewed all the recent published research on ginkgo, and presented its conclusions. We are just as critical of conventional medicine, and often tell our readers how to avoid questionable treatments. As for our "bias" against supplements, of the six supplements we've posted on the site so far, we're somewhat positive about three: St. John's wort, Cold-fX, and vitamin D.
--The Editors
Posted by: michaelg | April 15, 2010 3:32 PM