Is alcohol really a double-edged sword?

Many health conscious people believe that drinking in moderation is good for you.

I, like most doctors, was trained on this advice. The Dietary Guidelines for Americans – and for many other nations – used to recommend 1-2 alcoholic beverages a day, stating that “alcohol may have beneficial effects when consumed in moderation.” 

The science has since moved on, as have the nutrition guidelines, but public knowledge has not. The last thing the 2 billion people who enjoy alcohol want to hear is that alcohol’s alleged health benefits stand on shaky legs, and there are too many interested parties that continue to push this belief.

It’s an inconvenient truth, but the time has come to revisit the widely held idea that alcohol promotes health, because better data contradicts it.

Good for your heart?

The makings of wine as a health food are closely associated with the French paradox. Epidemiologic studies in the 1980s reported the paradoxical observation, that French people have lower rates of heart disease, despite their luxurious, butter-heavy diet. A 60 Minutes broadcast on the subject, ending with Morely Safer holding a glass of red wine, suggested that the secret to heart health “may lie in this inviting glass.” Sales of red wine shot up 40 percent the next year, and wine makers quickly adopted the health food halo.

Wine contains antioxidants and resveratrol, and might increase HDL, the good cholesterol. It seems perfectly plausible that it could improve vascular health.

Alas, there probably is no French paradox. Further studies found the paradox to be an illusion, a distortion, a result of inconsistent disease reporting and other factors.

The most persuasive evidence tying moderate drinking with health is the famous J curve, in which studies show that the risk of death declines with low levels of alcohol intake and then rises proportionately with higher levels of drinking. In other words, moderate drinkers have a lower risk than teetotalers.

Better research, however, flattened the J curve. After adjusting for confounders – the most important bias is reverse causality: sick, frail people tend to stop drinking – it looks like the more people drink the greater their risk of all kind mortality. Apparently, the question “do you drink” is very different from “have you ever been drinking.” When you remove recent quitters from the studies the positive effect of moderate drinking greatly diminishes.

What is moderation?

A new study that included 600,000 from 19 countries, published in the Lancet looked at alcohol consumption and the risk of cardiovascular disease, including heart attacks, stroke and heart failure. The study included only people who currently drink, in order to avoid the bias risk posed by including sick people who avoid alcohol for health reasons.

Alcohol was associated higher risk of stroke, heart failure, aortic aneurism and hypertensive disease, the greater the drinking the higher the risk, and there was no threshold at which drinking was safe, or seemed beneficial.

When it came to non-fatal heart attacks, however, moderate alcohol intake slightly lowered the risk.

Alcohol consumption was positively associated with all cause death, with the lowest odds of dying among people who drank about 5 drinks a week or less.

The authors estimate that for men, reducing drinking from the current suggested upper limit of 2 drinks a day, to no more than 5 a week, would add on average 1-2 years of life.

This study reached the same conclusion as better-conducted recent studies, and studies using genetic randomization.

As alluded above, it’s very hard to disentangle people’s lifestyle habits, and if you look at populations of never-drinkers, such as Seventh-day Day Adventists, who do have lower rates of heart disease, you can’t really know if not drinking alcohol improved or worsened their outcomes, as they usually lead a healthier than average lifestyle, and don’t smoke or eat meat. There is, however, a gene variant that is associated with lighter drinking that has been helpful in alcohol research. People who inherit a certain genetic variant of the enzyme that breaks down alcohol tend to drink less because they feel alcohol’s unpleasant side effects – such as nausea, headache and flushing – more readily. This, in effect, randomizes society by genes, and not by socioeconomic influences. 

People with this gene variant drink less, have fewer incidences of binge drinking, and many more of them abstain altogether, but there still was a wide variation in drinking among them, supporting the notion that there are societal influences, and that drinking culture affects drinking behavior – even among people with a genetic predisposition to drink less.

If alcohol in moderation indeed caused better heart health, we’d expect the people with the alcohol dehydrogenase 1B gene variant to show both above average and below average cardiac outcomes, and we’d expect those of them with the very lowest consumption – the abstainers– to have higher rates of heart attacks. 

But that’s not what studies found. Quite the contrary: those with the gene had 10 percent less coronary heart disease, as well as lower blood pressure, lower BMI, and lower ‘bad’ cholesterol levels across the board.

What about the rest of your body?

While the heart benefits of moderate drinking are questioned, the harms to many other organs are well known, and not in debate.

Alcohol is a known carcinogen.

A statement of the American Society of Clinical Oncology declares that alcohol drinking is an established cancer risk factor: “In the United States, it has been estimated that 3.5% of all cancer deaths are attributable to drinking alcohol. Alcohol is causally associated with oropharyngeal and larynx cancer, esophageal cancer, hepatocellular carcinoma, breast cancer, and colon cancer. Even modest use of alcohol mayincrease cancer risk, but the greatest risks are observed with heavy, long-term use.”

Alcohol is a leading cause of liver disease and liver cirrhosis.

Alcohol during pregnancy may harm the fetus and can cause Fetal Alcohol Syndrome.

Alcohol abuse affects more than 6 percent the US population; about 90,000 people die of alcohol related causes each year in the US.

Which brings us back to the question, is alcohol really a double-edged sword? Is alcohol in moderation beneficial?

Assessing risk and benefits

To reduce the risk of heart attacks, you can adopt several proven steps such as eating more vegetables and walking regularly. Not as seductive as a glass of wine, but almost risk free.

Not that I’m suggesting abstaining altogether. Alcohol, and wine especially, are a deeply cultural culinary joy, and I’m definitely not one to suggest that life should be approached with extreme caution and as an exercise of life prolongation.

On the other hand, alcohol is pushed so very hard that it becomes really hard to ignore or say no to it. Alcohol is almost the co-star in so many movies and TV shows, and is depicted as the ultimate way to relax or have fun – Grace in Grace & Frankie and Alicia in The Good Wife seem to sustain on a liquid diet. And why are there pink ribbons and tie-ins with breast cancer charities on alcoholic drinks? – reminder: alcohol is a risk factor for breast cancer, it’s particularly cynical to promote drinking to fight breast cancer.

I also have no idea why alcoholic drinks are one of the only products still exempt from displaying nutrition information. The caloric burden of alcohol might have tipped people who count every slice of bread towards greater moderation – every small glass of wine is about 120 calories.

Driving a car carries risk. Most of us assume that risk, because we want and need to go places. Taking on a calculated risk is fine. Not thinking about the risk might also be a fair enough choice.

But we can no longer pretend that alcohol – even in moderation – is something we should be doing for our health. 

Dr. Ayala