ore bad news for drinkers -and this time it’s even for low to moderate drinkers
! Even small quantities of alcohol consumed each day are significantly associated with an increased risk in cancer development, and may contribute up to 13% of the cancer incidents in Britain!
A new study [1
] published at the Journal of the National Cancer Institute
via Athens or other subscription types), looked at the alcohol consumption habits of about 1.3 million women being screened for breast cancer. The researchers then followed up the women for seven years and identified cancer cases through the National Health Service Central Registries.
The results were pretty clear, and the ultimate conclusion comes down to this (from a memo to the media
accompanying the study):
…these new results derived from such a large study population should give readers pause. Although previous epidemiological studies have suggested that there is a cardiovascular benefit associated with moderate alcohol consumption, the excess cancer risk identified in the current study may outweigh that benefit. “From a standpoint of cancer risk, the message of this report could not be clearer. There is no level of alcohol consumption that can be considered safe,”… [emphasis mine]
Just to become a little more specific (but only a little, mind you, cause time is limited these days): in the group of women studied (approximately 1.3 million), a quarter of them were non-drinkers. The vast majority (98%) of the remaining women were drinking on average a drink per day. It is important to note that such low-to-moderate drinking habits are very common in developed countries
such as the UK and the US. This has lead the authors to opine that:
Although the magnitude of the excess absolute risk associated with one additional drink per day may appear small for some cancer sites, the high prevalence of moderate alcohol drinking among women in many populations means that the proportion of cancers attributable to alcohol is an important public health issue
Moving on to the results, in the almost 7 years of follow-up, around 69,000 invasive cancers occurred (test statistics removed for clarity -only risk increase is shown. Briefly, all associations were strongly significant
with P values typically well below 0.01 except for rectum and liver cancer increases, 0.03 and 0.02 respectively):
Increasing alcohol consumption was associated with increased risks of cancers of the oral cavity and pharynx (increase per 10 g/d = 29%), esophagus (22%), larynx (44%), rectum (10%), liver (24%), breast (12%), and total cancer (6%). The trends were similar in women who drank wine exclusively and other consumers of alcohol. For cancers of the upper aerodigestive tract, the alcohol-associated risk was confined to current smokers, with little or no effect of alcohol among never and past smokers. [emphasis mine]
Another important note here: wine drinkers fared no better than other types of drinkers
. This is important because the media have a tendency to really love and promote red wine, with frequent reports of its benefits to the heart etc. Usually though, such articles unwarrantably extrapolate from in-vitro studies!
Following these results, it is not difficult to guess the conclusions of the authors (also obvious from the memo to the media mentioned above):
In middle-aged women, moderate alcohol consumption increases the risk of cancer overall; each additional drink regularly consumed per day may account for approximately 15 excess cancers per 1000 women up to age 75 in this age group in developed countries.
The authors could not identify correlations between heavy drinking and increase in the cancer risk due to the composition of the study group. However, an extrapolation in this case seems only reasonable
and is backed by previous studies demonstrating the grave consequences of heavy drinking.
For me it has been pretty clear for many years now: since you can easily get the benefits attributed to alcohol from other non-addictive sources or activities that will neither increase your chances of developing cancer nor make your liver look
like a dirty sponge
, there is no real reason to drink alcohol! Especially since I find its taste awful…
- Allen N et al. "Moderate Alcohol Intake and Cancer Incidence in Women," Journal of the National Cancer Institute 2009, vol 101, pp 296–305 [↩]