concludes a new observational study involving 50,000-plus British adults.
Being physically active – for example, by walking, house cleaning, or playing a sport – could be promoted as a risk-minimization measure for alcohol-related cancers, say the authors, led by Emmanuel Stamatakis, PhD, professor of Physical Activity, Lifestyle, and Population Health, University of Sydney, Australia.
The researchers found a “strong direct association between alcohol consumption and mortality risk of  alcohol-related cancers.”
Specifically, when compared with never drinkers, there was a significantly higher risk of dying from such cancers among drinkers who consumed “hazardous” and “harmful” amounts of alcohol, and also for ex-drinkers.
Notably, occasional drinkers and drinkers within guidelines did not have statistically significantly higher risks for alcohol-related cancer mortality.
But the analysis also found that among the bigger drinkers, the risks were “substantially attenuated” in physically active participants who met at least the lower recommended limit of activity (>7.5 metabolic equivalent task [MET]–hours/week).
That’s not a taxing amount of activity because, for example, general household cleaning results in 3 METs/hour and walking slowly translates into 2 METs/hour. However, nearly a quarter of survey participants reported no physical activity.
The study was published online May 14 in the International Journal of Cancer.
The new results require confirmation because the findings “are limited in their statistical power,” with small numbers of cases in several categories, said Alpa Patel, PhD, an epidemiologist at the American Cancer Society, who was not involved in the study. For example, there were only 55 alcohol-related cancer deaths among the 1540 harmful drinkers.
Patel stressed that, “based on the collective evidence to date, it is best to both avoid alcohol consumption and engage in sufficient amounts of physical activity.” That amount is 150-300 minutes of moderate or 75-150 minutes of vigorous activity per week for cancer prevention.
Her message about abstinence is in-line with new ACS guidelines issued last month, as reported by Medscape Medical News. The ACS’s guidance was criticized by many readers in the comments section, who repeatedly encouraged “moderation.”
However, the ACS also recommended moderation, saying, for those adults who do drink, intake should be no more than 1 drink/day for women or 2 drinks/day for men.
Study author Dr. Stamatakis commented on the alcohol debate.
“Any advice for complete abstinence is bound to alienate many people,” he told Medscape Medical News in an email. “Alcohol drinking has been an integral part of many societies for thousands of years.”
Dr. Stamatakis, who is an occasional beer drinker, also said, “there is no healthy level of alcohol drinking.”
This was also the conclusion of a 2018 study published in the Lancet, which stated that there is “no safe limit,” as even one drink a day increases the risk of cancer. A few years earlier, the 2014 World Cancer Report found a dose-response relationship between alcohol consumption and certain cancers.
However, epidemiological findings are not necessarily “clinically relevant,” commented Jennifer Ligibel, MD, a medical oncologist at the Dana-Farber Cancer Institute, Boston, Massachusetts, in a 2018 interview with Medscape Medical News.
Dr. Ligibel explained that there are 50 years of studies linking alcohol and cancers. “With the huge amount of data we have, even small differences [in consumption] are statistically significant.”
Dr. Ligibel cited an often-repeated statistic: for the average woman, there is a 12% lifetime risk of breast cancer. “If a woman consumes a drink a day, which is considered a low-level intake, that risk may become about 13% – which is statistically significant,” Dr. Ligibel explained.
But that risk increase is not clinically relevant, she added.