For some people, drinking in moderation can be beneficial. But at higher levels, it's deadly.
The health effects of alcohol have been debated for hundreds of years. The consensus today is that alcohol, like many things in life, can be either beneficial or damaging depending on how it's used.
After much investigation, researchers still share uncertainty about the benefits of alcohol, and whether benefits from modest drinking can offset alcohol’s risks.
Many researchers feel convinced that heart health benefits can be gained from mild to moderate alcohol drinking, defined as 1 drink per day for women and 2 drinks per day for men. (A "drink" equals 12 ounces of beer or wine cooler, 5 ounces of wine, or an ounce and a half of distilled spirits.)
Some experts disagree, saying that alcohol has not been proven to improve heart health. These experts worry that much-discussed surveys suggesting a heart benefit from alcohol have fooled us.
With heavier drinking, possible benefits are lost, and significant risks are present.
When it comes to alcohol, women are at a disadvantage that has very little to do with body size: A 250-pound woman is more likely to be damaged by alcohol than is a 140-pound man. That's because women absorb alcohol much more efficiently after it is consumed. Women also have higher levels of the liver enzyme that breaks down alcohol in the body, which allows them to metabolize alcohol about 20% faster than men. Although faster alcohol metabolism may seem to be an asset, it isn't a good thing. Much of the damage done to the body is caused not by alcohol itself but by acetaldehyde, a highly reactive byproduct of alcohol metabolism. When alcohol is broken down quickly, as it is in women, more of this toxic chemical is produced in less time, causing more damage.
Health benefits, still debated
The greatest potential health benefit of alcohol is its apparent ability to protect the arteries and the heart. Studies that observed the drinking patterns and heart health of very large groups of people have linked mild or moderate alcohol consumption to a lower risk of death from coronary heart disease. Similar research indicates that moderate alcohol use is linked with a lower risk of stroke.
Scientists have identified several reasons that alcohol may have a beneficial effect. Four theories have been suggested: First, alcohol increases blood levels of the "good" HDL (high-density lipoprotein) cholesterol, which clears plaque from the arteries. Second, alcohol affects the body's clotting mechanisms, decreasing the likelihood that a clot will block a blood vessel. Third, alcohol is linked to lower levels of C-reactive protein, a substance that is linked to lower levels of inflammation in the bloodstream. Finally, some researchers feel that alcohol may have anti-oxidant effects that may prevent injury in blood vessels.
Regardless of whether you drink beer, wine or spirits, the possible beneficial (and harmful) effects of alcohol are the same. However, there is some controversy about whether red wine has additional heart benefits that stem from something other than its alcohol content. Red wine — and red grape juice, for that matter — has high levels of flavonoids, natural chemicals that act as antioxidants and may decrease the harmful effects of "bad" LDL (low-density lipoprotein) cholesterol.
Despite any social benefits and despite its potential heart health benefits, alcohol has dangers. Even at moderate levels (just a drink or two per day), alcohol can cause serious problems:
Heavy drinking can have additional health consequences. The quantity of alcohol that has been considered heavy drinking has varied from one study to another. Most doctors currently consider "problem drinking" to be regular consumption of more than 14 drinks per week (or more than 4 drinks in 1 day) if you are a man and more than 7 drinks per week (or more than 3 drinks in 1 day) if you are a woman.
Adults who choose to drink should remember that the health benefits come only from low to moderate consumption. For those who don't drink, most experts don't recommend starting. The risk of alcoholism is real, (see When Enough Is Enough ) and the only way to avoid developing that disease is never to start drinking in the first place.