No effect on heart disease and mortality among moderate drinkers
Most studies have found that binge drinking is associated with a loss of alcohol's protective effect against ischemic heart disease (IHD) and most studies have found an increase of coronary risk among binge drinkers.
This study followed 26,786 men and women who participated in the Danish National Cohort Study in 1994, 2000, and 2005 and sought to see if binge drinking increased the risk of IHD or all-cause mortality among "light-to-moderate" drinkers: (up to 21 drinks/week for men and up to 14 drinks/week for women). A "drink" was 12g.
"Binge drinking" (more that 5 drinks on an occasion) did not show differences in risk of ischemic heart disease (coronary disease) or total mortality than among always moderate drinkers. These results are somewhat different from results of many other epidemiologic studies that have shown increased risk of health problems (even higher risk of coronary disease) to be associated with what was referred to as "binge drinking."
Why there were no adverse effects of binge drinking in this study has provoked considerable discussion among members of the Forum. The assessments of alcohol were based on consumption in the week prior to the examination, so data was not available to judge whether or not binge-drinking episodes occurred rarely or regularly. Data was available for smoking, education, physical activity, BMI, and self-reported hypertension and diabetes. There was a strong increase in IHD risk and mortality from binge drinking among heavy drinkers, but the authors were comparing outcomes in binge vs. non-binge drinkers among subjects in the "light-to-moderate" categories, and so in all comparisons, the relative risk of IHD and all-cause mortality was higher for non-drinkers than for all other categories of drinkers.
The general consensus of opinion among Forum members is the definition of "binge drinking." The rapid consumption of more than 5 drinks on an empty stomach surely has different effects than the consumption of alcohol over several hours with food, such as during a prolonged dinner. The rate of consumption strongly affects the consequences of alcohol; the speed of drinking and context should constitute part of the definition of 'bingeing' and not just the total number of drinks.
The Forum concludes that "binge drinking," however defined, is not a healthy pattern of alcohol consumption. But the circumstances of consumption (rate of consumption, with or without food, etc.) may also be important in its definition and in judging its effects on health.
The Forum does not take the results of this single study to support binge drinking. What the Danish results suggest is that the occasional "excess" embedded in a moderate consumption pattern is not shown to be harmful in this study. As recognized in responsible drinking guidelines from Australia, Canada and the US, occasional episodes of consumption greater than the recommended daily levels do not necessarily change the classification of a normally moderate drinker into that of an abuser.