The protective benefit of wine is thought to be due to it containing
resveratrol, which inhibits the initiation and progression of
malignancy, according to a new survey carried out in Denmark.
The findings confirm evidence that this form of cancer is comparatively
rare, with only 156 cases occurring in the study of 28,000 individuals
over 13 years.
Previous investigations have revealed an association between alcoholic
beverages and cancer of the oesophagus, but their findings have
been limited as they relied on retrospective evidence. The new
findings are much stronger as the re-searchers followed three
on-going prospective surveys into the health of the Danish people.
They combined the subjects from these groups and thus monitored
15,000 men and 13,000 women for between two and nineteen years.
Participants drinking habits were recorded at the outset, and
then analysed in relation to any tumour that developed over the
subsequent years. Alcohol intake was measured in units consumed
per week .
The results showed that, in comparison with abstainers, individuals
who drank 10.5 - 31.5 8g units per week in the form of beer or
spirits only were three times more likely to contract upper gastric
tract cancer. However, subjects with the same overall intake,
but who consumed 30% or more of their intake as wine, halved their
risk of developing the cancer in comparison to non-drinkers. The
risk for alcohol abusers (defined as those consuming over 69 units
a week) was twelve times greater than that of abstainers. Smokers
of 20g or more of tobacco each day were also five times more likely
to develop upper gastric tract cancer than non-smokers.
The underlying reason for the differing effects of wine and other
alcoholic beverages in this research is as yet uncertain.A partial
explanation is offered in that wine contains substances such as
resveratrol which inhibit the initiation and progression of malignancy.
Other possible influences are nitrosamines, which can become carcinogenic
when altered by biochemical changes within the body. Nitrosamines
occur in beer and spirits but are present in insignificant quantities
in wine. Further research is required to clarify these possible
mechanisms behind the observed variations in cancer rates in different
types of drinker.
Source: 'Population based cohort study of 'the association between
alcohol intake and cancer of the upper digestive oesophageal tract.'
British Medical Journal 1988 317, M.Gronbaek, U.Becker et al.