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Iedere dag één glas rode wijn en de kans op
prostaatkanker wordt gehalveerd.*
Uit een diepgaande studie door het gerenomeerde
kankerinstituut “Fred Hutchinson’s Public Health Sciences Division” blijkt
dat het drinken van 1 glas rode wijn per dag de kans op prostaatkanker met wel
50% reduceert en de kans op een agressieve vorm wel met 60% reduceert. Verder
blijkt dat andere alcoholhoudende dranken dit effect niet hebben, ook witte wijn
veel minder. Dit komt omdat de antioxidant resveratrol verantwoordelijk geacht
wordt voor deze reductie en resveratrol wordt het meest aangetroffen in de schil
van blauwe druiven. In deze studie heeft men gekeken, in tegenstelling tot
eerdere studies die zich tot enige jaren beperkten, naar de voedingsgewoontes
van ouderen gedurende heel hun leven. Opgemerkt wordt nog dat het drinken van
meer dan dat ene glas per dag de kans op ziektes weer doet toenemen en dus
achterwege moet blijven.
A Glass Of Red Wine A Day May
Keep Prostate Cancer Away
SEATTLE – Drinking a glass of
red wine a day may cut a man's risk of prostate cancer in half, and the
protective effect appears to be strongest against the most aggressive forms of
the disease, according to a new study led by investigators at Fred Hutchinson
Cancer Research Center.
The findings, by Janet L.
Stanford, Ph.D., and colleagues in Fred Hutchinson's Public Health Sciences
Division, appear online in The International Journal of Cancer.
"We found that men who
consumed four or more glasses of red wine per week reduced their risk of
prostate cancer by 50 percent," Stanford said. "Among men who consumed
four or more 4-ounce glasses of red wine per week, we saw about a 60 percent
lower incidence of the more aggressive types of prostate cancer," said
Stanford, senior author of the study. "The more clinically aggressive
prostate cancer is where the strongest reduction in risk was observed."
Stanford and colleagues found no
significant effects – positive nor negative – associated with the
consumption of beer or hard liquor and no consistent risk reduction with white
wine, which suggests that there must be a beneficial compound in red wine that
other types of alcohol lack. That compound, Stanford and colleagues believe, may
be an antioxidant called resveratrol, which is abundant in the skins of red
grapes but much less so in the skins of white grapes. The compound is also found
in peanuts and raspberries and is available as a dietary supplement, which has
been suggested to protect against cardiovascular disease.
Laboratory studies indicate that
resveratrol influences a variety of biological pathways that are important in
cancer development. For example:
* As an antioxidant, it helps
sweep dangerous, cancer-causing free radicals from the body.
* As a potent anti-inflammatory
agent, it blocks certain enzymes that promote tumor development.
* The compound also reduces cell
proliferation, curtailing the number of cell divisions that could lead to cancer
or the continued growth of cancer cells.
* It also enhances apoptosis, or
programmed cell death, which helps rid the body of cancerous cells.
* It may act as an estrogen,
reducing levels of circulating male hormones such as testosterone that fuel the
growth of prostate cancer.
While the researchers found that
the risk of prostate cancer decreased 6 percent for every glass of red wine
consumed per week, Stanford is quick to point out that research shows the law of
diminishing returns comes into play when consumption increases beyond
moderation. "From a public-health standpoint, it's difficult to recommend
any alcohol consumption given the risks associated with heavy consumption, from
increased overall cancer risk to accidental injury and social problems. But for
men who already are consuming alcohol, I think the results of this study suggest
that modest consumption of red wine – four to eight 4-ounce drinks per week
– is the level at which you might receive benefit. Clearly other studies show
that more than that may have adverse effects on health."
For the study, the researchers
interviewed 753 newly diagnosed Seattle-area prostate-cancer patients as well as
703 healthy controls who served as a comparison group. Detailed information
about tumor aggressiveness (such as tumor grade and disease stage) was obtained
through the National Cancer Institute's Seattle-Puget Sound Surveillance,
Epidemiology and End Results cancer registry.
"Even though this study is
based on relatively small numbers, the results are very intriguing and suggest
that the potential beneficial effect of red wine and resveratrol – if indeed
resveratrol is the active chemopreventive agent involved – would be very
important, because it's the more aggressive forms of prostate cancer than are
most important to prevent," she said.
A particular strength of the
study, Stanford said, is that the participants were relatively young, ranging in
age from 40 to 64, and the majority were under 60.
"By focusing on men under
age 65, whose incidence of prostate cancer is much lower than that of older men,
we can tease out the effect of a particular environmental exposure on cancer
risk, such as wine consumption, more easily than if we were looking at men
across the entire age range," she said. This is particularly true when
studying complex diseases such as prostate cancer in which numerous genetic and
environmental factors are thought to play a role over an individual's lifetime.
Another strength of the study is
that in addition to being surveyed about lifetime alcohol consumption,
participants were asked about a variety of other risk factors for prostate
cancer, such as diet, family history of cancer, screening for prostate cancer
and tobacco use, all of which were taken into account and adjusted for when
analyzing the data.
While the majority of studies to
date have assessed the effects of overall alcohol use on prostate-cancer risk,
fewer studies have attempted to compare the effects of wine versus beer versus
hard liquor, and only one previous study has compared the impact of red versus
white wine on prostate-cancer risk, said Stanford, also a professor of
epidemiology at the University of Washington School of Public Health and
Community Medicine.
The previous study, the
Netherlands Cohort Study, evaluated prostate-cancer risk in relation to white
and red wine consumption. Increased risks were found in men who consumed
"white and fortified wines," but not red wine, as compared to
nondrinkers, although there was not a consistent trend in risks with levels of
intake. Interestingly, among men who consumed 15 or more grams of red wine per
day (about one and a half glasses per day), there was an overall 18 percent
reduction in risk and a 16 percent lower risk of advanced-stage prostate
cancers. The Netherlands Cohort Study was initiated in 1986 and collected
information by self-administered mailed questionnaires that asked about alcohol
consumption during the prior year only. Thus, the Netherlands Cohort Study
results only reflect associations with recent wine consumption, as investigators
were unable to examine lifetime intake as was done in the current Fred
Hutchinson study.
"One of the reasons we
wanted to do this study is because overall, most of the scientific literature
– around 17 studies to date – haven't shown a consistent relationship
between alcohol consumption and prostate cancer," Stanford said. "Some
have shown an increase, some a decrease, and most no association whatsoever.
Part of the problem, we believe, is that few of the studies have attempted to
sort out the effects of different types of alcohol intake over a man's
lifetime."
Stanford and colleagues plan to
seek funding to conduct a larger study to see if their results hold up. In
collaboration with Norm Greenberg, Ph.D., of Fred Hutchinson's Clinical Research
Division, they also plan to test the effects of resveratrol on mouse models of
prostate cancer to see if giving mice this chemical compound will reduce the
onset of prostate cancer and/or decrease the aggressiveness of the disease.
The first author of the study, W.
Marieke Schoonen, M.S., formerly a graduate student in Stanford's group, is now
a doctoral student at the London School of Hygiene and Tropical Medicine. The
National Cancer Institute, National Institutes of Health and U.S. Department of
Health and Human Services funded the research.
###
Fred Hutchinson Cancer Research Center, home of two Nobel laureates, is an independent, nonprofit research institution dedicated to the development and advancement of biomedical technology to eliminate cancer and other potentially fatal diseases. Fred Hutchinson receives more funding from the National Institutes of Health than any other independent U.S. research center. Recognized internationally for its pioneering work in bone-marrow transplantation, the center's four scientific divisions collaborate to form a unique environment for conducting basic and applied science. Fred Hutchinson, in collaboration with its clinical and research partners, UW Medicine and Children's Hospital and Regional Medical Center, is the only National Cancer Institute-designated comprehensive cancer center in the Pacific Northwest and is one of 38 nationwide. For more information, visit the center's Web site at http://www.fhcrc.org. (okt. 2004)