Light to moderate drinking of alcoholic beverages does not increase the risk of lung cancer, according to a study that involved more than 9,000 people over two generations. The study, appearing this week in the Journal of the National Cancer Institute, found that people who consume one to two alcoholic drinks a day have no greater chance of developing lung cancer than do nondrinkers.
Data from the study was adjusted so that the effects of smoking, known to be the major cause of lung cancer, were statistically eliminated as a factor in the conclusion, the researchers report.
Alcohol drinking has been associated with lung cancer in some past studies, but the findings are considered by some experts to be uncertain because drinking and tobacco smoke exposure often go together. The new study attempts to avoid this problem by removing the confounding effects of smoking, the researchers report.
Data reached back 50 years
Dr. Luc Djousse of Boston University School of Medicine, the first author of the study, said his group used data from the famed Framingham, Mass., study that followed the health of thousands of participants since 1948. The research also includes data from the Framingham Offspring Study, which started in 1971 and involves children of the original study participants.
For the lung cancer study, Djousse and his co-authors examined health and survey data from 4,265 subjects in the original Framingham study, and 4,973 from the offspring study.
The alcohol study was funded by the National Heart, Lung and Blood Institute. Djousse and a co-author received grants from
research organizations supported by the beer and the wine industries.
Researchers found 269 cases of lung cancer among the study participants. They were matched by age, gender and smoking history with participants who were not diagnosed with lung cancer. The researchers then compared the drinking habits of the group, and concluded that light to moderate alcohol consumption was not a factor in the cancers.
2 daily drinks increase risks
Djousse said that only one subcategory — offspring who drank more than two drinks a day — showed an increased risk of lung cancer. The incidence of cancer in this group was double that of the nondrinkers of the same age, smoking history and gender.
However, Djousse said the numbers in this subcategory are too small to draw a valid statistical conclusion.
Dr. Mary C. Dufour, deputy director of the National Institute on Alcohol Abuse and Alcoholism, said the researchers doing the study make up “a highly respected team using an extensive database,” but that the results do not eliminate alcohol drinking as a risk for lung cancer.
Dufour said that the Djousse study analyzed only the effects of one to two drinks a day on lung cancer rates. She said other studies that looked at heavy drinkers — five drinks or more a day — found a direct link between alcohol and lung cancer.
“The jury is still out on the heavy drinkers,” Dufour said.