Lots of people drink.  Most think they “don’t drink too much.”  They “only drink socially.”  Or “just a couple of drinks a few nights of the week.”

But when it comes to health, how much is enough?

A new study looking a national guidelines has come up with surprising results. The short answer is “less is best.”

Perhaps a lot less.

Alcohol and the Heart

About thirty years ago Richard Peto (now Sir Richard) found small amounts of drinking led to decreased risks of heart attack.  Many patients, and certainly the drinks industry, was heartened by these results.  Daily drinking was “healthy.”

But only if you look at heart attacks. Only.

A new study in Lancet proved a bit more exhaustive than most.  It involved 600,000 people in 19 countries who were current drinkers (teetotalers are epidemiologically different in subtle ways) who drank, were followed prospectively, and whose results could be controlled for diabetes, hypertension, and the standard confounders. The main aim was to look at cardiovascular disease, but all cause mortality – including the threat that alcohol poses for cancer, liver disease, accidents and dementia – got included.

The authors were interested in the sixty four dollar question – when does alcohol consumption get “dangerous?”

What they found was that more than 100 grams of alcohol (there’s 28 grams in an ounce)  a week had clear impacts on survival.  Many of them were non-linear – going up as people’s consumption went up.

What surprised were the effects on heart disease.  The finding that drinking small amounts cut back on heart attacks held up.

But if you looked a stroke, coronary disease outside heart attacks, heart failure, fatal hypertension or aortic aneurysm, all the death rates went up.  The researchers finally concluded, in language worthy of legal scholars, that regarding cardiovascular disease, “there were no clear risk thresholds below which lower alcohol consumption stopped being associated with lower disease risk.”  In English, that means there was no level of drinking that was not associated with more heart disease.

Yet cardiovascular disease constitutes in this study only about one fifth of alcohol’s overall effect on mortality.

What’s In a Drink

Ask Americans “what’s in a drink of alcohol” and you often get very different answers.  Some report an “ounce” of alcohol as a “large glass of wine” or “two fingers” in a shot glass.

The actual American “standard drink” is a half ounce of alcohol, 14 grams.  It’s what you usually find in one beer, five ounces of “most” wines, 1.5 ounces of vodka or whiskey.  When it comes to estimating how much they drink, people are often poor self-reporters.  Typically they underestimate.

As they dramatically underestimate the physical effects of alcohol.

Mortality and Booze

Perhaps the most alarming results of this international study involved  mortality.  As people drank more, the increased death rate became curvilinear – going up faster.

It was particularly bad for those who drank 350 grams of alcohol or more a week.  By American reckoning, that’s 25 drinks, or three and a half drinks a day.  The researchers decided to look at this in terms of years of lost life, from age 40 on.

The older one got, the more the effects returned towards a straight line relationship between drinking and death rates.  That partly means people who made it to older ages were more resistant to disease than those who died before.  But if you looked at steadily drinking 3.5 drinks a day at age 40, the predicted  years of life lost was about five.  Even for those drinking 200 grams a week, or about two drinks a day, the figure approached two years.

Two years may not sound like much, but that’s close to what all of medical care is supposed to add to one’s lifespan.  How many would be willing to foreclose all medical care for their life starting at age 40?  More importantly, mortality statistics do not include the many other effects of alcohol on morbidity, including recent research that “minor” drinking in the middle aged increases the risk of dementia.

Bottom Line

There are many reasons to drink – socializing, conviviality, culture, amusement, pleasure, tradition.  However, physical health, as measured by mortality, may not be one of them.

Heavy drinking, here defined as 3.5 standard American drinks a day, is associated with the kind of mortality statistics you generally see with smoking.  And that’s neglecting its effects on mood, family, well-being, accidents, work, social and economic and performance, and memory.  Plus, as with radiation, there may be no clear “safe” level of alcohol consumption.

It’s a good time to think before you drink –  and think about what drinking does to your thinking.