October 2004—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.
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."
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
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.
potent anti-inflammatory agent, it blocks certain enzymes that promote tumor
—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.
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."
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.
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.