A study released last Tuesday in the December 23/30 issue of JAMA, the Journal of the American Medical Association stated that adults who used ginkgo biloba for several years did not have a slower rate of decline compared to adults who received a placebo. Many feel this study misses the boat.
It’s important to know – this is NOT a new study. This study is using the same data from a study previously published in 2008. Now there’s no problem doing this, per se. I mean, the data’s been collected so why not run another statistical analysis on it? However, the danger here is that many experts had issues with the study parameters from 2008, so any conclusions drawn still have the same concerns.
For example, some believe the researchers did not start with a healthy enough population, so to evaluate ginkgo in this case is really not very helpful. For example, if you want to determine whether or not an herb can prevent a cold, you probably don’t want to use a group of people who already have colds! Similarly, according to Daniel Fabricant, Ph.D., vice president for scientific and regulatory affairs at the Natural Products Association,
“When one considers that age-related cognitive decline may initiate in healthy adults as early as their 30s, it would seem that if the authors were indeed serious about investigating prevention as a secondary outcome, they would have selected a population that was situated closer to the onset of cognitive decline instead of one where its effects most likely have already taken hold.”
Below, is an email I received from Brian Tanzer, M.S. from Reliance Private Label Supplements. Normally, I would link to his blog post, but Brian doesn’t have one. Therefore, I received permission to include his email below.
Greetings:
By now, I’m sure most of you have either read or have seen the report on the ineffectiveness of ginkgo biloba (EGB 761) in preventing cognitive decline in older adults. I read the published study, which isn’t actually a “new” study at all. In this “study”, the researchers reported on cognitive decline as an apriori (gained through deduction, not experimentation) secondary outcome of the 2008 GEM or Ginkgo Evaluation of Memory study. So, basically, it’s like saying okay I have a dozen eggs. If I make 2 hard-boiled eggs, then I have will have 10 eggs left. There’s no need to actually go and boil the two eggs to test this. You can, through deductive logic, figure out the result. These researchers used the power of statistics to take the data from the 2008 study and apply it to a different study objective. If you look at the two articles, here is what you see:
2008 Study Objective: To determine effectiveness of Ginkgo biloba vs. placebo in reducing the incidence of all-cause dementia and Alzheimer’s Disease (AD) in elderly individuals with normal cognition and those with mild cognitive impairment. Translation: To determine whether taking ginkgo would prevent the onset of dementia.
Study Conclusions: Ginkgo was not effective in reducing either the overall incidence rate of dementia or AD incidence in elderly individuals with normal cognition or those with mild cognitive impairment.
2009 Objective: To determine whether Ginkgo biloba slows the rates of global or domain-specific (memory, language, attention, etc.) cognitive decline in older adults. Translation: Determine the affect of ginkgo on the rate of decline in cognitive function.
Study Conclusions: The use of Ginkgo biloba did not result in less cognitive decline in older adults with normal cognition or with mild cognitive impairment.Here we go again. The medical establishment using the “magic bullet” theory to test a compound’s affect on a specific disease process. Some things to consider:
1. The first several years of treatment were not captured by detailed cognitive evaluations, as most follow up occurred a few years after the start of treatment.
2. The average age of study participants was 79, with a range of 79-96.
3. An “active” control group might have been helpful to have as a comparison to the ginkgo and placebo group. Could have included a group using the drug Aricept, which is one of the few drugs used in Alzheimer’s Disease/dementia.
The first issue is important as a lot of important data is missing which could have showed if a person was in fact suffering some cognitive decline during the time period for which no detailed evaluations were done.
The second is very important, as most of the published clinical trials on ginkgo have evaluated its positive affects on healthy, non-cognitively impaired individuals. Many of these studies show ginkgo increased short-term memory and concentration. The studies were also done on younger subjects, and according to Mark Blumenthal, Founder of The American Botanical Council “This age group is not typical of the age of both healthy people and those with mild cognitive impairment who use ginkgo for improving mental performance”. The third point, as you can read below under “Ginkgo Compared to Donepezil (Aricept)” ginkgo produced the same improved-memory results without the side effects of the prescription drug. Aricept is what we call a cholinesterase inhibitor. This is an enzyme that breaks down the neurotransmitter acetylcholine. Aricept reduces the activity of the enzyme allowing more acetylcholine to reach nerve cells, potentially enhancing normal brain activity.
Consider this little “valuable” piece of information: At the end of the JAMA study, the following financial disclosure information was provided:
Keep in mind there are 11 researchers involved in this publication, and 18 in the original 2008 study-By the way Aricept was developed by Eisai Health Care and co-promoted by Pfizer. Two of the researchers are listed on both publications. They are:
- Judith Saxton, Ph.D reports having served as a consultant and having received honoraria as a speaker for Pfizer/Eisai. She has received research support from both
- Steven Dekosky, MD serves on the advisory board of or consulting for Eisai and Pfizer among many other pharmaceutical and biotechnology companies; too many to bother listing.
See any connection here!
Most credible researchers know that Ginkgo doesn’t cure or prevent Alzheimer’s Disease/dementia. What it can do is potentially help support cognitive function, increase circulation and provide antioxidant support to the brain. I included some brief reviews of studies below. Keep in mind, just as vitamin E is a good antioxidant and chromium shown to potentiate insulin function, lutein help support the health of the macula and may help reduce the risk for macular degeneration, Ginkgo biloba itself is not a sole treatment or cure. Vitamins, minerals, amino acids, fatty acids, herbs, etc. do not function independent of each other. They work synergistically, each making its own biochemical/physiological contribution. We have seen studies like this time and time again, and we will continue to see them. Studies where one nutrient, herb, etc. is tested the way a drug would be, alone, and proposed to perform biological “magic”, oftentimes with a very predictable end result (in the case of nutrients). It happened with Beta carotene in lung cancer patients, selenium in prostate cancer and many others. We cannot study nutrients the same way as synthetic drugs. It’s our job to educate our retailers and consumers, teaching them how to take information such as this and put it in perspective. Nutrition is a very dynamic science. Some of the information available is good, accurate and supported by valid scientific studies, while a small percentage is the complete opposite. My job is to keep you folks well informed and up to date on the latest information as best I can.
In health,
Brian Tanzer, M.S.
The bottom line for me is, we need more research. Many studies have shown ginkgo can be a very effective tool while others create some doubt. I think too often, we look to the most recent study as the only one that matters.
I’m curious, have you or anyone you know tried ginkgo? What were your results?
Great nice blog thanks for sharing guys keep it up…..