The Australian media was abuzz last week with a report that alcohol consumption increases the chances of prostate cancer. Two drinks a day will increase your risk by 20%. The risk increased with the number of drinks consumed in a day.
Before I pour my home brew down the drain, there are a few things I need answered.
(If you haven't read my previous post, now's a good time. I'll wait.)
Could alcohol consumption cause/increase the risk of prostate cancer? Possible.
Could prostate cancer risk cause drinking? Improbable.
Could a third factor be in play? Possible. Here are a few possible other factors:
People who drink large amounts of alcohol a day are often overweight. Is BMI a factor?
The consumption of chips, nuts and snack foods is probably proportional to drinks consumed.
Big drinkers often eat more meat.
Is consumption of other foods an issue - fibre, greens, fruit?
Do drinkers live longer, due to the heart benefits of alcohol, and get cancer due to longevity?
That will do. I'm sure we could come up with more. You can begin to see the difficulty of extracting two issues from a very complex life-matrix.
Is a crud factor in play? Possibly. Sometimes a big survey like this finds statistical significance where no practical significance exists or will average out differences in reports.
Compare the following two extracts from studies into prostate cancer and alcohol consumption:
Our present study suggests that consumption of beer or liquor is not associated with prostate cancer. There may be, however, a reduced relative risk associated with increasing level of red wine consumption. Int. J. Cancer: 113, 133–140 (2005).
Wine or beer consumption was unassociated with prostate cancer; however, moderate liquor consumption was associated with a significant 61–67% increased risk of prostate cancer. International Journal of Epidemiology 2001;30:749-755
Looks as if beer is neutral, red wine gets a sort of a plus and spirits get a sort of a minus.
So does the report mean anything?
Too early to tell really but I will put a punt on the benefits of moderate alcohol consumption outweighing the possible down side.