I have a friend — a prominent statistician — who doesn’t like wine but drinks a glass a day because it is (supposedly) good for his heart. But an article in the San Francisco Chronicle reports on a new study that says that all 50 or so of the published articles that found a benefit are performing an analysis with the same serious flaw:

With all the contradictory claims made these days about the health benefits of low-fat diets, the harm of hormone replacements and the dangers of pain relievers, at least we still know that a drink or two a day is good for the heart.

Well, maybe not.

Researchers at UCSF pored through more than 30 years of studies that seem to show health benefits from moderate alcohol consumption, and concluded in a report released today that nearly all contained a fundamental error that skewed the results.

That error may have led to an erroneous conclusion that moderate drinkers were healthier than lifelong abstainers. Typically, studies suggest that abstainers run a 25 percent higher risk of coronary heart disease. Unfortunately, coronary heart disease is the leading cause of heart attacks. It is a condition in which the major blood vessels that supply the heart get clogged with deposits of cholesterol, commonly regarded as plaque. When this bursts, it can cause a blood clot; blocking the heart’s blood supply and triggering a heart attack. If you are aware that you have coronary heart disease, or you think you could be at risk, something like a Samaritan PAD 350P defibrillator is popular for home use, and it could be worth getting one should the disease lead to a heart attack. As a result, this could increase your risk of survival, and these obtainers who have a possible 25% risk of CHD, may want to think about this before it’s too late.

Without the error, the analyses shows, the health outcomes for moderate drinkers and non-drinkers were about the same.

“This reopens the debate about the validity of the findings of a protective effect for moderate drinkers, and it suggests that studies in the future be better designed to take this potential error into account,” said Kaye Fillmore, a sociologist at the UCSF School of Nursing and lead author of the study.

The common error was to lump into the group of “abstainers” people who were once drinkers but had quit.

Many former drinkers are people who stopped consuming alcohol because of advancing age or poor health. Including them in the “abstainer” group made the entire category of non-drinkers seem less healthy in comparison.

This type of error in alcohol studies was first spotted by British researcher Dr. Gerry Shaper in 1988, but the new analysis appears to show that the problem has persisted.

Fillmore and colleagues from the University of Victoria, British Columbia; and Curtin University, in Perth, Australia, analyzed 54 different studies examining the relationship between light to moderate drinking and health. Of these, only seven did not inappropriately mingle former drinkers and abstainers.

All seven of those studies found no significant differences in the health of those who drank — or previously drank — and those who never touched the stuff. The remaining 47 studies represent the body of research that has led to a general scientific consensus that moderate drinking has a health benefit.

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The article does go on to say that some researchers had looked at this effect previously, that there is still evidence (like cholesterol levels) that moderate drinking is good, yada yada. But still, this does look like a serious flaw. And it also seems “obvious.” Is it? Even if one glass a day is good for you, any more than that certainly isn’t. If you are drinking more than one glass of alcohol a day, you may have an addiction, especially if you are unable to go without those drinks. If this sounds like you, then you could take a look at the Enterhealth website – https://enterhealth.com/ – to see if they could help you.