For cardiovascular disease mortality, meta-analyses of four studies found an 18 percent lower risk of death among moderate drinkers compared with non-drinkers. Broken down, there was a 23 percent lower risk in female drinkers and 18 percent lower risk in male drinkers. The lower risk of cardiovascular disease mortality was rated as moderate certainty.
The ICCPUD review
The ICCPUD subcommittee’s report offered a darker outlook on moderate drinking, concluding that “Alcohol use is associated with increased mortality for seven types of cancer (colorectal, female breast, liver, oral cavity, pharynx, larynx, esophagus [squamous cell type]),” and “Increased risk for these cancers begins with any alcohol use and increases with higher levels of use.”
The review modeled lifetime risks of cancer and death and relative risks for a long list of problems, including infectious diseases, non-communicable diseases, and injuries. Also, it didn’t just focus on non- drinkers versus moderate drinkers, but it assessed the relative risk of six levels of drinking: one drink a week; two drinks a week; three drinks a week; seven drinks a week (one a day); 14 drinks a week (two a day) and 21 drinks a week (three a day).
Overall, the analysis is very much a rough draft. There are some places where information is missing, and some of the figures are mislabeled and difficult to read. There are two figures labeled Figure 6, for instance and Figure 7 (which may be Figure 8), is a graph that doesn’t have a Y-axis, making it difficult to interpret. The study also doesn’t discuss the level of potential bias of individual studies in its analyses. It also doesn’t make note of statistically insignificant results, nor comment on the certainty of any of its findings.
For instance, the top-line summary states that “In the United States, males and females have a 1 in 1,000 risk of dying from alcohol use if they consume more than 7 drinks per week. This risk increases to 1 in 100 if they consume more than 9 drinks per week.” But a look at the modeling behind these estimates indicates the cutoffs of when drinkers would reach a 0.1 percent or 1 percent risk of dying from alcohol use are broad. For males, a 0.1 percent lifetime risk of an alcohol-attributed death is reached at 6.5 standard drinks, with a 95 percent confidence interval spanning less than one drink per week and 13.5 drinks per week. “This lifetime risk rose to 1 in 100 people above 8.5 drinks per week,” the text reads, but the confidence interval is again between one and 14 drinks per week. So, basically, anywhere between about one and 14 drinks a week, a male’s lifetime risk of dying from alcohol may be either 0.1 or 1 percent, according to this modeling.