A new study, which was published in The Lancet lately, has shown that consuming more than 100 grams of alcohol per week, which is roughly 5 and a half glasses of wine or 2.5 liters of beer is increasing the risk of a person's risk of stroke, coronary disease, heart failure, fatal hypertensive disease, and fatal aortic aneurysm.
This limit is much lower than the suggested guidelines by many countries. In the US, the maximum tolerable amount is 196 grams for men and 98 grams for women. The German Nutrition Society considers 140 grams for men and 70 grams for women to be tolerable. In other countries, such as Canada, Italy, Portugal and Spain, the levels are also higher.
What does this mean? Not a lot, according to the American Council on Science and Health, a pro-industry science education nonprofit organization. Dr. Alex Berezow, one of the council’s writers has published an article on the organization’s website this Friday, saying that the study was not conducted correctly. Amongst the arguments against the study these were the most significant:
- The study did not properly adjust for all confounders. A confounder (also confounding variable, confounding factor or lurking variable) is a variable that influences both the dependent variable and independent variable causing a spurious association. A famous example for this distorting effect was a study on the consumption of coffee, which concluded that coffee caused pancreatic cancer. The authors of this study neglected at that time thze fact that most coffee drinkers are also smokers, which is a much more likely cause for cancer. In the recent strudy the scientist adjusted for age, sex, smoking, and diabetes, which is good but not sufficient, because it neglects the fact that people, who drink every day alcohol very often have also a stressful job, a poor diet or lack of exercise.
- The study showed that people drinking 100 grams of alcohol per week had a lower risk of all cardiovascular diseases. Only when broken up into various subtypes the data showed higher risks for some types and lower risks for other types of cardiovascular disease (CVD).
- The study showed a reduced live expectancy of half a year, which is not really significant in a man’s lifespan of about 80 years, for people drinking 200 grams of alcohol (about 2 drinks) per week. Only when people had 2 to 3.5 drinks per day or roughly 3.5+ drinks per day the life expectancies decreased by 1-2 years and 4-5 years, respectively, what is not a surprise, given the fact that those people are already considered alcoholics.