White Lightning Axiom: Redux: Ginkgo

Tuesday, October 17, 2006



Over the years, I've heard many MS and Non-MS folk lament over the loss of the intellectual acumien. This is blamed on many things: MS, college parties, aging, etc. Of course, we would all like to be as bright and energetic as we were years before. But with age comes wisdom, or horse sense. And along for the ride we find the imp of lost accuity in our mental facilities.

I wanted my ability to balance a spreadsheet in my mind while remembering a half years worth of appointments back. I wanted to be able to pick up highly abstract ideas and integrate them with my higly organized base of knowledge that was once like stacking childrens blocks. Enter stage right, the snake oil salesmen. Ginko is the cure for what Ails you my brothers!!! Just a few pills a day and you'll look down on Oppenheimer like a dullard! Mozart and Bach will be organ grinders! Jefferson, Plato and the rest will welcome your new found brillance as a breath of fresh air. And I ate the tripe up as if it were a feast of the kings. Swill down those energy drinks for they are the abrosia of the gods. Reality hit not too much further down the road but too late to spare me a healthy dent in the budget.

I'm going to pick on one suppliment today. You see, I wouldn't put too much faith in Ginko, the FDA has reviewed the studies and the relationship between memory and ginko suppliments is highly suspect due to the way that the studies have been done. Researchers have been funded by 'interests' that have a conclusion they want to market, but need some supporting facts. Facts they are willing to pay for with grants. And those grants will keep coming so long as the results are sufficient enough to keep the public duped. Given that, a true double-blind test with a sufficiently robust base would be extraordinary in expense and would return only marginal results. Nothing a purveyor of mercury as a cure for consumption would be able to use.

Let's get a rudimentary understanding of how memory works. Essentially, you have short term memory and long term memory. The the hippocampus is understood to be involved in spatial learning and declarative learning ... which is built upon short term memory. Damage to connective white matter in patients and subsequent memory flaws is a indicator of this. It could be that damage to this connective tissue, or to a pathway develope through the damaged region is actually the cause of the deficit.

Given this, we know very well that once an axion is damaged, it can heal via scarring or die. These cells are not replaced. We are forced to make due with what we have available after an age when the brain ceases growing. Brain development continues into adolescence. Then, cell death begins and we must reroute pathways around the degrading areas as best as we can. So the only salvation we can hope for is some way to help us reorganize our vital information. Now, let's look at the claims:
Here we see some bad news:

    The brain: mechanisms of ginkgo biloba that cause cognitive impairment
    Studies have shown that this extract can affect the brain in four major ways through blood circulatory and neurotransmitter systems, as an antioxidant, and a component of glucose utilization. In both antioxidant activity and in the circulatory system, ginkgo allows for increased blood flow to the brain. In the circulatory system, blood vessels are widened, allowing for increased blood flow as well as reduced risk of stroke. The aggregation of blood platelets and the formation of clots are also inhibited.
But it goes on to say, 'Never mind that sub-dermal hemotoma!':
    Ginkgo biloba extract plays a role in the body’s use of glucose by increasing its absorption in the frontal and parietal cortex. As a result, areas of the brain that are vital for processing sensory information are made more efficient. Neurotransmitters in the brain undergo changes when ginkgo enters the body. The production of norepinephrine is increased as well as the release of gamma-amino butyric acid. Lastly, as an antioxidant, ginkgo biloba lessens free radical activity that can damage neurons and alleviate the effects of cerebral ischemia.
Does it work every time? No.
    Over-the-counter treatments often claim to improve memory, attention and cognitive function. In a six-week double-blind study (placebo-controlled with parallel group), two hundred and nineteen participants over the age of sixty were randomly assigned to receive a treatment of ginkgo (40 mg, three times per day) or a matching placebo. Outcomes were measured by tests of verbal and nonverbal learning and memory, attention and concentration and also questionnaires. After analyzing this sample, no significant differences were seen between the two groups. These results show that ginkgo biloba did not alter the performance of elderly adults on neuropsychological tasks.

    Ginkgo biloba Heath Benefits to those without previous cognitive impairment
    Although ginkgo is known to affect older adults, its effect on those without mental impairments is still questionable. For six weeks, a group of healthy adults was given 40 mg of ginkgo extract three times a day or a placebo. The results showed no difference in memory scores, self-reported perception, or rating by spouses, friends, and relatives after the duration of the trial. Ginkgo provided no short-term benefits in people with healthy cognitive function.

    However, a similar study that was conducted has conflicting results. Again using healthy people, a group received 180 mg a day of ginkgo for six weeks. Compared to placebo, the supplement improved memory score and significantly improved self-perception of memory. In this study, those who received ginkgo rated their overall ability to remember as "improved" compared to those receiving the placebo. This correlates well with previous studies indicating a potential short-term benefit to ginkgo supplementation.
So, if you have damage, this is not going to help. The article goes on to state that after a time, the results degrade and you soon develop a 'tolerance' and your gains fade away.
Then there is the less than desirable effects of the wonderous brain supplement.
    Adverse Ginkgo Biloba Side Effects and interaction with other drugs
    The most serious side effect associated with ginkgo biloba is the increased risk of bleeding as it acts as a blood thinner. For this reason, it is not suggested that individuals taking anti-coagulants, such as aspirin, should try this supplement. In addition, those taking MAOI anti-depressent drugs or pregnant women are in danger. Convulsions are also a possible side effect after consuming a large amount of gingko nuts. The seeds of this plant are toxic and can potentially destroy vitamin B within the body.

    Other side effects of Gingko biloba, it may cause spontaneous hyphema (bleeding from the iris into the anterior chamber of the eye) in rare cases. Restlessness, diarrhea, nausea, and vomiting can result from taking this supplement. Other severe side effects, although rare, can include headaches and GI tract and dermatology reactions. In a double-blind placebo study, the adverse effects of ginkgo were tested. There was no difference found between the control and experimental group in terms of adverse effects. Although positive effects were seen as a result of consuming the extract, outcomes varied with duration of the treatment.

    Interaction with Other Supplements
    Although very few, there are some possible interactions for ginkgo biloba and other supplements. For example, if used in conjunction with St John’s wort, side effects such as muscle stiffness, rapid heartbeats, fever, restlessness and sweating may occur. The combination of ginkgo and hawthorne can possibly affect blood pressure levels. When taken with products that also increase the risk of bleeding, such as garlic and vitamin E, the risk for the symptom is merely amplified. Oppositely, blood sugar levels can be lessened if ginkgo is taken with a bitter melon supplement. However dosage may have to be altered when taken more than one supplement concurrently.
More warnings of Adverse Effects:

    Ginkgo extract appears to be very well tolerated. Infrequent side effects include mild gastrointestinal disturbances, headache, and allergic skin reactions. Four cases of serious bleeding, including subdural hematoma, have been reported. One case suggests an interaction with warfarin (Coumadin®) and one an interaction with aspirin. In one of the few studies examining a possible ginkgo-warfarin interaction, there was found no increase in the INR (prothrombin time) when volunteers taking warfarin were given ginkgo. Considering the antiplatelet activity of ginkgo and the limited information available, patients should be advised to discuss ginkgo and warfarin therapy when used together with their physician or pharmacist.

    The risks and benefits of taking ginkgo with aspirin, clopidogrel, ticlopidine or other antiplatelet agents (including fish oil and high dose vitamin E) must be weighed carefully and patients should be advised of the bleeding risk.
And the most reputable study, what of that? The FDA thought it was good enough, no? No. In fact, if the FDA HAD approved it, it would have been in direct violation of their own requirements. Here is the skeptic's line:
    But in dozens of published studies, including a major trial in the prestigious Journal of the American Medical Association (JAMA), the evidence doesn't support ginkgo as a treatment for Alzheimer's disease or for boosting memory power in otherwise healthy people.
    One recent study of gingko for Alzheimer's avoided some of these pitfalls-the study published in JAMA in 1997. Hundreds of patients with early Alzheimer's took 120 mg of ginkgo per day for a full year, and were tested periodically. The study suggested that ginkgo delayed the progression of the symptoms for up to six months. These widely-publicized findings influenced many people to take ginkgo in hopes of preventing or treating Alzheimer's disease.

    But when other researchers took a close look, they found flaws-some fairly serious. For one thing, some of the people in the placebo group did not worsen as much as they should have without treatment. "It was not as it ought to be, and it leaves you wondering if these are truly patients with dementia," observes Paul Solomon, Ph.D., a professor of psychology at Williams College in Massachusetts. Also, the change in mental skills detected by the study was small-about 25 percent of what would be expected in a patient treated with existing Alzheimer's drugs, Solomon says.

    The real kicker was the fact that researchers could not tell the difference between treated subjects and those on placebo. In other words, the study could not prove that the effect of ginkgo on these people was clinically significant. Based on information provided by caregivers and family members, the researchers did document a difference, although it was relatively small: for every seven people treated with ginkgo, caregivers and family members detected improvement in one person on ginkgo.

    "The outcome measure that is required in the United States is that observers who are blinded can notice a difference in the patients, and no one could notice any difference," Solomon notes. "If that study was submitted to the FDA to have a drug approved, it would not be acceptable."
    Gingko works in some ways similar to prescription anticoagulation medication, and it is thought to enhance the effects of drugs such as Coumadin or warfarin. A few patients on these medications who also started taking ginkgo have been reported to suffer intracranial hemorrhages shortly after beginning the gingko, and it is considered unwise to mix the herb with these drugs.
    Other vitamin and herbal anti-platelet supplements, such as garlic and Vitamin E can also increase the effects of gingko. Therefore it is important to discuss the use of this herb with your physician, especially if you are taking prescription medications or other herbal supplements. There are no data on the safety of gingko in pregnancy, and it is not recommended for use in children or infants.
    This study, together with results from other trials, suggest that the published benefits of ginkgo - improved memory, attention, and mental flexibility - do not persist beyond the first few days of treatment. The authors of this study have reported a similar trial in healthy young volunteers, and found a similar lack of effect on memory and attention after 6 weeks; they also found no effect on mental flexibility in young subjects.

    Clearly the measurable effects of ginkgo are small and fleeting, at best. It seems likely that tolerance to the substance develops; in other words, the body fails to react to repeated doses because the tissues become 'used to' the presence of the molecules and fail to react to it, or the substance is broken down and removed more rapidly by the body over time, which is a known occurrence with certain drugs. Either way, taking ginkgo in the recommended doses has little to recommend it.

    Because ginkgo decreases blood platelet aggregation (stickiness), there is some concern that it may increase risk of intracranial (brain) hemorrhage; in fact, there have been several reports of bleeding complications associated with ginkgo use. It would be unadvisable, therefore, for people to self-medicate with ginkgo at high doses in the hope of obtaining effectiveness.
In closing, don't be fooled. You may get a boost, you may not. It might even be better for you to take aspirin instead of ginko. It's good for your heart, helps with strokes and costs about a buck for a bottle of 100 pills.

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