I was contacted the other day by Barbara Shukitt-Hale, one of the authors of the
study of blueberries and their effects on memory in rats (I suppose my questions
had been sent to her by someone on TIPS--thank you, mysterious stranger). If you
recall, the researchers concluded that antioxidants are the likely source of the
effects on memory (and motor coordination) in the rats they studied. I asked her
some questions about the study:
(1) Is there any evidence that antioxidants in general improve memory in humans?
(2) If so, what kinds of memory?
(3) If so, is this effect limited to elderly adults (as seems to be true for
ginkgo biloba....an herb we talked about a few weeks ago on TIPS))?
Barbara Shukitt-Hale wrote:
> Jeff:
> ....
> In regards to your questions. There is a general theory of aging
> (developed by Harman in the 50s) which says that oxidative stress and the
> free radicals it generates might be responsible for the deficits seen in
> aging, "The free radical theory of aging". There is lots of evidence to
> support this theory but the theory has not be definitively proven.
> However, there is evidence that antioxidants can provide some benefits in
> aging and other diseases. The most popular antioxidants are Vitamins E and
> C. There is much less evidence for antioxidants and memory improvements,
> although there is some evidence which says that they are beneficial. I
> just co-authored a manuscript to this effect, but unfortunately it is not
> published yet. I have enclosed the references as an attached word perfect
> file. Most memory that is tested is spatial memory, specifically working
> and reference memory.
>
> One herbal supplement that has been implicated in memory improvement is
> Ginkgo biloba. However, from what I have read it works best for people who
> have senile dementia already and it is unknown if it helps normal elderly.
>
> Ours is the only research that I know of that has studied fruits and
> vegetables and memory. No one has done this in humans yet. In our first
> study we prevented aging effects, but I don't know if fruits and vegetables
> would improve memory in young adults.
>
So, it seems to me that we should be cautious in generalizing the results to
humans. In fact, I used this research as an example of how the popular press may
exaggerate the applicability of findings to humans. From the discussion in my
class and with my colleagues, it seems that some people are eating blueberries
now because of this research. Not that this is bad in itself; but the conclusions
of the study, although promising, may be more limited than these people are
hoping.
Jeff
--
Jeffry P. Ricker, Ph.D. Office Phone: (480) 423-6213
9000 E. Chaparral Rd. FAX Number: (480) 423-6298
Psychology Department [EMAIL PROTECTED]
Scottsdale Community College
Scottsdale, AZ 85256-2626
"The truth is rare and never simple."
Oscar Wilde
"No one can accept the fundamental hypotheses of scientific psychology
and be in the least mystical."
Knight Dunlap
