In a new study this week, researchers in Japan have found a link between lifetime drinking to an increased risk of cancer—only the latest bit of research to suggest that even light drinking over a lifetime can be bad for us.
The study, published Monday in the journal Cancer, relies on data from a decades-long research project tracking the health of patients across Japan who had been admitted to a hospital. In addition to having their medical history documented, volunteers were asked about their drinking habits, including how much they drank daily and how long they had been drinking altogether. Using this data, the study’s authors compared roughly 63,000 adult patients diagnosed with cancer to the same number of patients without cancer of similar age, sex, and hospital admission date, a type of study known as a case-control.
Compared to those who reported never drinking, the authors found an increased risk of cancer among people who would be considered light to moderate drinkers. Those who drank a standard drink a day (defined as a 2-ounce shot of whiskey, 6-ounce glass of wine, or a 17-ounce glass of beer), for instance, were 5 per cent more likely to develop cancer, even after accounting for factors like smoking, high blood pressure, obesity, and other known risk factors for cancer.
Other research has pointed to an increase in cancer risk from drinking, particularly breast, head and neck, and liver cancer, but the authors say theirs is one of the first to centre around people living in Japan.
“In Japan, even light to moderate alcohol consumption appears to be associated with elevated cancer risks,” they wrote.
In the grand scheme of things, a relative 5 per cent increase in cancer risk is not earth-shattering. The authors noted, for instance, that things like smoking as well as Hepatitis B and C infection carry a much higher associated risk of cancer. And it’s possible that these results might not be applicable to other populations, since native Japanese residents are more likely to carry genetic variations that make it harder for their bodies to break down alcohol. These sorts of studies can only indirectly suggest that something causes cancer, not directly prove the connection.
But this is just the latest study to show that light alcohol use isn’t necessarily harmless, contrary to years of savvy messaging from the alcohol industry and even some doctors. While some studies have suggested that light alcohol can improve heart health, other research has cast doubt on that assumption. And it’s likely most people don’t even know about the alcohol-cancer link in the first place.
A study in the UK earlier this year, for instance, found that just 20 per cent of women getting screened or treated for breast cancer knew that drinking alcohol was a risk factor for breast cancer. Perhaps more shocking was that only 49 per cent of health care staff interviewed were aware of the link.
In any case, while no one’s stopping you from enjoying your holiday drink this Christmas, it’s safe to say that we could all probably benefit from a little bit more moderation.